ANNEX WI-FI RDS
© ciccioCB 2023
COPYRIGHT
The Annex firmware including the AnnexToolKit and this manual are Copyright 2017-2020 by Francesco Ceccarella (ciccioCB).
The compiled object code (the .bin file) for the Annex firmware is free software: you can use or redistribute it as you please except for commercial purposes. It is not allowed to distribute or embed it into products that are sold or for any other activity making or intended to make a profit.
The compiled object code (the .exe file) for the AnnexToolKit utility is free software: you can use or redistribute it as you please except for commercial purposes. It is not allowed to distribute or embed it into products that are sold or for any other activity making or intended to make a profit.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
This manual is distributed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 France license (CC BY-NC-SA 3.0)
The above copyright notice and this permission notice shall be included in all copies or redistributions of the Software in any form.
License and credits
Adafruit BNO055 Orientation Sensor library is written by KTOWN is Copyright (c) Adafruit Industries. It is released under MIT license.
TFT_eSPI display Library is Copyright © 2017 Bodmer. It is released under FreeBSD license.
Adafruit NeoPixel library is Copyright (c) Adafruit. It is released under MIT license.
Makuna/NeoPixelBus library is Copyright © by Michael C. Miller. It is released under LGPL license.
Adafruit PWM Servo Driver Library is Copyright (c) Adafruit. It is released under MIT license.
Arduino Library for Dallas Temperature ICs is Copyright (c) Miles Burton <miles@mnetcs.com>. It is released under LGPL license.
OneWire Library is Copyright 1999-2006 Dallas Semiconductor Corporation and Copyright (c) 2007, Jim Studt.
Adafruit DHT Humidity & Temperature Sensor Library is Copyright (c) Adafruit. It is released under MIT license.
ESP8266 and ESP32 Oled Driver library is Copyright (c) 2016 by Daniel Eichhorn and Copyright (c) 2016 by Fabrice Weinberg. It is released under MIT license.
ESP8266Ping is Copyright (c) Daniele Colanardi. It is released under LGPL license.
ESP AsyncTCP library is Copyright (c) 2016 Hristo Gochkov. It is released under LGPL license.
ESP AsyncWebServer library is Copyright (c) 2016 Hristo Gochkov. It is released under LGPL license.
IRremoteESP8266 library is Copyright (c) Sebastien Warin, Mark Szabo, Ken Shirriff, David Conran. It is released under LGPL license.
uRTCLib is Copyright (c) 2015 Naguissa (naguissa.com@gmail.com). It is released under LGPL license.
BME280 library is written by Limor Fried/Ladyada for Adafruit Industries. It is released under BSD license,
APDS9960 library is written by Shawn Hymel for Sparkfun Electronics. It is released under Beerware license.
PID Library is written by Brett Beauregard (br3ttb@gmail.com). It is released under MIT license.
MQTT library pubsubclient is Copyright (c) 2008-2015 Nicholas O'Leary. It is released under MIT license
MFRC522 library is written by Miguel Balboa.
The Javascript Editor EditArea is Copyright © 2008 Christophe Dolivet. It is released under LGPL license.
The base of the interpreter comes from the original project "MiniBasic" by Malcom Mclean.
The MFRD522 library is written by Miguel Balboa and is released as free and unencumbered software released into the public domain.
Contributions
A very big thank you to Robin Baker (Electroguard) for his great involvement in the project by supporting all the tests on the real hardware (bought with his money), and all the advices that allowed me to add a lot of functionality, not to mention the Huge work he did while documenting the project on the website.
Content :
HOW the interpreter works with the HTML code and Objects :
Ret = FILE.COPY(filename$, newfile$)
Ret = FILE.RENAME(oldname$, newname$)
Ret$ = FILE.READ$(filename$, [line_num] | [start, length])
FILE.APPEND filename$, content$
MAX7219 8-Digits 7-segment display
NeoPixel based WS2812b Dot Matrix DIsplay
ULTRASONIC DISTANCE SENSOR HC-SR04
DHT xx Temperature / Humidity Sensors
BNO055 Absolute Orientation Sensor
BME280 Combined humidity and pressure sensor
APDS9960 Digital Proximity, Ambient Light, RGB and Gesture Sensor
RFID MFRC522 RFID cards reader
Writing NUID for UID changeable card (4 byte UID version)
DIMMER.SETUP pin_in, pin_out, [,invert [,swap]]
TUYALAMP.INIT [max_current_RGB, max_current_WHITE]
Server data requests (GET and POST)
- WGET$(server$, port, [,header])
- WPOST$(server$, body$, port [,header])
- WPOST$(url$, body$ [,header])
- WGETASYNC[(] server$, port, [,header [,ping]] [)]
- WGETASYNC[(] url$, [,header [,ping]] [)]
Ret = MQTT.Fingerprint(fingerprint$)
Ret = MQTT.Connect(login$, pass$ [id$])
Ret = MQTT.Connect("", "", [id$])
Ret = MQTT.Publish(topic$, message$)
Ret = MQTT.Subscribe(topic$ [,Qos])
Ret = MQTT.UnSubscribe(topic$)
CONVERT.FROM_IEEE754(iee754_bin)
CONVERT.MAP(number, fromLow, fromHigh, toLow, toHigh)
APDS9960.GESTURELED (intensity)
CONVERT.FROM_IEEE754(ieee754_bin)
CONVERT.MAP(number, fromLow, fromHigh, toLow, toHigh)
EMAIL from$, to$, subject$, message$
FILE.COPY(filename$, newfile$)
FILE.RENAME(oldname$, newname$)
INSTR([start], string$, pattern$)
I2C.READREGBYTE (i2c_address, register)
MQTT.Fingerprint(fingerprint$)
MQTT.Connect(login$, pass$, [id$])
MQTT.Publish(topic$, message$)
PID1.COMPUTE( current_value, target_value)
WORD.COUNT( string$ [,delimiter$])
WORD.FIND( string$, find$ [,delimiter$])
BAS.FTP$( host$, login$, password$, file$, folder$)
CSSID$(object_id, object_style)
FILE.READ$(filename$,[line_num] | [start, length])
IMAGEBUTTON$(path, label [,id])
LISTBOX$(variable$, "option1, option2, option3, ..." [, height] [,id])
METER$(variable, min, max [,id])
REPLACE$(expression$, find$, replacewith$)
SLIDER$(variable, min, max [,step] [,id])
STR$ (number [,format$ [,toint]])
WGET$( http_server$, port [,header] )
WPOST$(server$, body$, port [,header])
WPOST$(url$, body$, [,header])
WORD$(string$, position [,delimiter$])
WORD.DELETE$(string$, position [delimiter$])
WORD.EXTRACT$(string$, lead$, trail$)
WORD.GETPARAM$( setting$, parameter$ [,separator$])
COUNTER.SETUP cnt, pin [,mode]
EMAIL.SETUP server$, port, user_name$, password$ [, debug]
EMAILASYNC from$, to$, subject$, message$
FILE.APPEND filename$, content$
FUSION.MADGWICK ax, ay, az, gx, gy, gz
FUSION.MADGWICK ax, ay, az, gx, gy, gz, mx, my, mz
FUSION.MAHONY ax, ay, az, gx, gy, gz, mx, my, mz
I2C.SETUP sda_pin, scl_pin [,freq [,stretch]]
I2C.READREGARRAY i2c_address, register, nb_of_bytes, Array()
I2C.WRITEREGBYTE i2c_address,register, value
I2C.WRITEREGARRAY i2c_address, register, nb_of_bytes, Array()
INTERRUPT pin_no, {OFF | label}
IR.INIT pin_rx | OFF [, pin_tx]
MAXDISPLAY.PRINT msg$ [,‘brightness]
MAXSCROLL.SETUP nb_devices, CS_pin [,reverse]
MAXSCROLL.SHOW pos [, brightness]
MAXSCROLL.OSCILLATE [brightness]
NEO.PIXEL led_pos, R, G, B [, disable]
NEO.PIXEL led_pos, COLOR [, disable]
NEO.STRIP led_start_pos, led_end_pos, R, G, B [, disable]
NEO.STRIP led_start_pos, led_end_pos, COLOR [, disable]
NEOSCROLL.SETUP nb_devices, pin [,serpentine]
NEOSCROLL.SHOW pos [, brightness]
NEOSCROLL.SCROLL [‘brightness]
NEOSCROLL.OSCILLATE [‘brightness]
OLED.INIT orientation [,model]
OLED.RECT x,y, width, height [,fill]
OLED.CIRCLE x, y, radius [, fill]
OLED.PRINT x, y, text$ [background]
ONERROR ABORT or ONERROR IGNORE or ONERROR SKIP [nn] or ONERROR CLEAR or ONERROR GOTO label
PIN.MODE pin_number, mode [,PULLUP]
PIN.TONE pin, freq [,duration]
PRINT expression[[,; ]expression] ...
PRINT2 expression [[,; ]expression] ...
RTC.SETTIME Year, Month, Day, Hours, Minutes, Seconds
SERIAL.MODE baudrate [, bits, parity, stop]
SERIAL2.MODE baudrate, pin_tx, pin rx [, bits, parity, stop]
SERVO.SETUP id, pin_number | OFF
SETTIME Year, Month, Day, Hours, Minutes, Seconds
SPI.SETUP speed [,data_mode [, bit_order]]
ST7920.RECT x,y, width, height [,fill]
ST7920.CIRCLE x, y, radius [, fill]
ST7920.PRINT x, y, text$ [background]
TM1637.PRINT msg$ [, brightness]
TM1637.SETUP data_pin, clock_pin [, bit_delay] [, display_type]]
TM1638.PRINT msg$ [, brightness ]
TM1638.SETUP data_pin, clock_pin, strobe_pin
TFT.BMP filename$, [x, y [, back_color] ]
TFT.CIRCLE x, y, radius [, fill]
TFT.INIT CS_pin, DC_pin, orientation [Display_width, Display_height, Variant]
TFT.PRINT expression [[,; ]expression] ...
TFT.RECT x, y, width, height, color [ [,fill] ,[round_radius] ]
TFT.TEXT.COL color [,backcolor]
URLMSGRETURN msg$ [,content_type$]
WGETASYNC [(] server$, port, [,header [,ping]] [)]
WGETASYNC [(] url$, [,header [,ping]] [)]
WIFI.APMODE SSID$, password$ [, channel] [, IP$ , MASK$]
WIFI.CONNECT SSID$, password$ [, BSSID$] [, IP$ , MASK$ [, GATEWAY$]]
WLOG expression[[,; ]expression] ...
WORD.DELPARAM setting$, parameter$, [,separator$]
WORD.SETPARAM setting$, parameter$, value$ [,separator$]
DIM array(size) [, …] [= init1, init2, …]
Introduction:
Annex WI-Fi RDS (Rapid Development Suite) is a version of the "basic" language developed to run on low cost ESP8266 WIFI devices.
It takes from the original concept of ESPbasic - which I cooperated on and contributed to in the past - but is a completely re-designed breakaway project designed to offer improved functionality and reliability.
The intention was to create a Basic language for the ESP which complies as much as possible with the original GWbasic / Visual Basic - from which it shares many concepts / ideas / syntax - and also from the excellent project "Micromite" of Geoff Graham.
The base of the interpreter comes from the original project "MiniBasic" by Malcom Mclean.
The text editor comes from the original project "EditArea" by Christophe Dolivet.
Functionalities:
- Includes an internal IDE so can be programmed directly using your web browser without any additional utility (even with your phone/tablet).
- Syntax highlighting with context sensitive Help
- A programmable web server including file server
- Supports OTA (over the air) update.
- Support async events (interrupts, timers, web access, UDP, ….)
- Breakpoints, immediate execution of commands, display of variables, single step.
- A basic interpreter with floating point variables (double precision) and string variables, multidimensional arrays (float and string), user defined subroutines.
- Access to any available I/O pin for input/output, PWM and Servo.
- Errors Handling .
- Support TCP (HTTP) GET and POST for communications
- Support for UDP for communications.
- Support for sending Emails using SMTP SSL servers
- Support for AJAX communications
- Support for ESP-NOW communications
- Support for MQTT communications
- Support for FTP communications
- Accompanying utility suite includes Flasher, File Manager, HTML Converter, Backup/Restore to bin or zip, integrated Serial Port Monitor, OTA (over the air) update server and UDP Console.
- IMU / AHRS Fusion algorithms 6 DOF and 9 DOF (Madgwick and Mahony)
- 4 Channels PID controller
The following devices are supported directly with dedicated commands / functions :
- DHT11, DHT21 or DHT22 Temperature / Humidity Sensors
- DS18B20 Temperature sensor
- LCD HD44780 with I2C interface module (1, 2 or 4 lines with 16 or 20 chars per line)
- LCD Display based on chipset ST7920 with 128x64 pixels monochrome
- OLED Display based on chipset SSD1306 or SH1106 with 128x64 pixels monochrome
- TFT Display based on Chipset ILI9341 with 320x240 pixels and 16 bits colors
- TM1637 4 and 6 digits 7-segments display
- TM1638 8 digits 7-segments display including 8 leds and 8 buttons
- MAX7219 8 digits 7-segments display
- MAX7219 8x8 dot matrix display modules
- Neopixel WS2812 led strips
- Neopixel WS2812 8x8 dot matrix display
- PCA9685 PWM/SERVO module
- Infrared interface with many RC protocols (transmission and reception)
- RTC module (DS1307 or DS3231)
- HC-SR04 ultrasonic sensor for distance measurement
- BNO055 Absolute Orientation Sensor
- BME280 Combined humidity and pressure sensor
- APDS9960 Digital Proximity, Ambient Light, RGB and Gesture Sensor
- RFID MFRC522 cards reader
Interpreter:
The basic interpreter works by reading a script file saved to the esp local disk filing system (SPIFFS).
In order to use less RAM, the user script is copied from the disk into a dedicated area in the flash memory where it is executed, so only the list of the program lines, the branch labels and the list of the user defined subroutines get loaded into memory.
This is slower compared to other approaches, but permits maximum memory to be available for user variables and program use.
Another performance consideration is that the ESP8266 must be capable of executing several activities in the background (web server, file server, ..) so needs sufficient free memory for running such tasks, and those parallel tasks must obviously have an impact on script performance..
So performance-wise, the interpreter is not particularly fast, but it should be fast enough for most tasks you may require. I tried to run some "1980s BASIC benchmark" taken from "the back shed" forum and I can say that the performance is around 2 to 4 times slower than a micromite @48 Mhz; but (IMHO) that’s not bad considering all the additional connectivity and web functionalities provided by the esp module.
Basic program lines :
A typical script line should comply with the following syntax :
[label:] command [argument1 [,argument2 …..]]
Script lines may contain several commands on the same line if separated by the colon character ":".
[label:] command1 [argument1 [,argument2 …..]]: command2 [argument1 [,argument2 …..]]
It must be noted that use of several commands on the same line is not recommended and will cause program errors if the line contains GOSUB or user defined subroutine calls.
All program jumps (eg: GOTO, GOSUB) are referenced by their branch label names - line numbers are not referenced in scripts, they are merely available in the editor as a programming convenience if wished.
NOTE : The gosub and the call to user defined subroutines must be used alone on the script line.
Branch labels
Branch labels should not be named the same as a command name, and must follow the same format as variables (see below).
A branch label definition must begin the line, and a colon (":") must terminate the label definition.
Any references to the defined label (GOTOs and GOSUBs etc) do not use a colon.
Example :
|
b = 10 a = 20 : c = 30 GOSUB LABEL1 END LABEL1: print "Label1" RETURN |
Variables:
The interpreter has 2 types of variables:
- Floating Point (double precision)
- String
Floating point variables can store numbers with decimal point; they can also store integer numbers with a precision equivalent to 32bits.
Strings contain sequences of characters (example "my program") and must be terminated by "$".
The strings are not limited in size, they are only limited by the amount of memory available.
NOTE: The string variables cannot contain the character with ASCII code 0 (zero) because it is used internally as an end of string delimiter.
The variables are defined as any name starting with an alpha character (a, b, ..z) followed by any alphanumeric character (a..z, 0..9); it can also include the "_" (underscore).
The case is don’t care, so ‘’Num" is equivalent to "nuM".
The name length is limited to 31 characters maximum, including the "$" for the strings.
There are no limits in terms of number of variables; the only limit is the RAM memory available.
Example:
|
NUM = 10.56 myString$ = "this is My String" this_is_my_value$ = "ESP8266" number = 8826621 |
Numeric variables and string variables are managed separately so the same name can be used; this means that A and A$ are different variables that can coexist at the same time (even if this could lead to confusion).
Constants:
The numeric constants can have the following format :
A = 5 : Z = 1.5
B = 1.23456E5 -> same as 123456
C = 1.23456E+5 -> same as 123456
D = 1.23456E-3 -> same as 0.00123456
The string constants are simply defined as a text between quotes:
A$ = "This is my string" : B$ = "another string"
The strings can include the character " (quote) simply typing it two times :
A$ = "this is ""MY"" string"
The | (vertical bar) can also be used as a string literal.
This permit to include the " (quote) easily inside a string constant :
A$ = |this is a "string" constant|
The hexadecimal constants can be defined simply prefixing it with &H :
E = &HABCD -> equivalent of decimal 43981 (hexadecimal constant)
F = &HA0 -> equivalent of decimal 160
The binary constants can be defined simply prefixing it with &B :
E = &B00000101 -> equivalent of decimal 5 (binary constant)
F = &B10000001 -> equivalent of decimal 129
The octal constants can be defined simply prefixing it with &O :
E = &O377 -> equivalent of decimal 255 (octal constant)
F = &O17 -> equivalent of decimal 15
Arrays:
Arrays are defined using the DIM command.
Their names follow the same rules as the regular variables and are followed by parenthesis (brackets) containing the index. The subscript always starts from 0.
The scope of the Arrays is always global (see next paragraph).
Example:
DIM A(100) define a floating point array with 101 elements (index from 0 to 100)
DIM ABC$(50) define a string array with 51 elements (index from 0 to 50)
A(15) = 1234.5678
ABC$(49) = "Hi friend!"
The arrays can have up to 5 subscripts (dimensions), examples:
DIM A(50,50) -> create a floating point array with 51*51 elements (2601)
DIM J$(4, 4, 4) -> create a string array with 5 * 5 * 5 elements (125)
NOTE:
The numerical Arrays are always initialised at 0 with the command DIM.
The string Arrays are always initialised as null string with the command DIM.
There are no limits to the number of arrays or their size, the only restriction is the RAM memory available.
The arrays can be re-dimensioned using the same command DIM.
In this case all the existing elements will maintain the previous value except the new elements that will be initialised at 0 or null string.
Example :
|
DIM A(5) ' all the elements are initialised at 0 A(0) = 123 Print A(0) ' print 123 Dim A(10) Print A(0) ' print the same value 123 Print A(10) ' print 0 |
In addition the elements of the arrays can be initialised with a given value during the command DIM.
Example :
DIM A(5) = 0, 1, 2, 3, 4, 5 ' set A(0)= 0, A(1)= 1, A(2)=2, ….
The same can be done with string arrays.
Example :
DIM A$(5) = "zero", "one", "two", "three", "four", "five"
Scope of the variables:
Variables and arrays defined in the main code are global, therefore any variable is accessible from any part of the code after it has been previously defined there.
Variables and arrays defined inside “user defined” subroutine (SUB) are visible only inside that sub and inside all the code called by that subroutine; their content (and their memory space) is removed at the end of the SUB
The LOCAL command permits defining local variables inside of "user defined" subroutines; this permits to use the same name of an “already existing” variable locally without modifying the original.
As for all the variables defined inside SUB, they will disappear at the end of the subroutine.
Example:
|
A = 10 B = 20 C = 30 mysub "Hello" PRINT A,B, C END
SUB mysub(a$) LOCAL A,B A = 123 B = 456 C = 789 D = 8888 PRINT A$, D END SUB |
In this example, calling the user-defined subroutine "mysub" will not modify the content of the global variables A and B (defined locally) but will modify the content of the variable C (not defined locally) and the variable D will disappear at the end of the SUB.
Bases of the language
The keywords recognized by the interpreter can be defined into 3 classes:
● Operators
● Commands
● Functions
The Operators are symbols that tells the compiler to perform specific mathematical or logical manipulations.
Commands and Functions both execute an action, but functions also return a data value.
For example PRINTis a command and SIN() is a function whereas the ‘+’ in a = b + 5 is an operator.
The string functions are always followed by the "$" symbol if they return a string value.
In addition to commands and functions there are all the internal interpreter internal commands that are part of the language itself.
OPERATORS AND PRECEDENCE
The following operators are available. These are listed in the following tables by order of precedence. Operators on the same line are processed with a left to right precedence.
Arithmetic operators:
|
^ |
Power |
|
* / \ MOD |
Multiplication, division, integer division and modulo (remainder of the division) |
|
+ - |
Addition and subtraction |
Shift operators:
|
x << y x >> y |
These operate in a special way. << means that the value returned will be the value of x shifted by y bits to the left while >> means the same only right shifted. They are integer functions and any bits shifted off are discarded and any bits introduced are set to zero. For more information about the kinds of bitwise shifts, see Bitwise shifts. |
Logical operators:
|
<> < > <= >= = |
Not Equal, less than, greater than, less than or equal to, greater than or equal to, equal |
|
AND OR NOT XOR |
Conjunction, disjunction, negation, Exclusive OR |
String operators:
|
<> < > <= >= = |
Not Equal, less than, greater than, less than or equal to, greater than or equal to, equal |
|
+ & |
Add strings together |
Bitwise operators:
|
AND OR XOR NOT |
Binary AND, binary OR, binary exclusive OR, binary negation For more information about the bitwise operators, see Bitwise Operators |
The operators AND, OR and XOR are integer bitwise operators. For example PRINT (3 AND 6) will output 2.
Expressions beginning with open parenthesis ‘(‘ are always considered numerical but the parser is able to determine if an expression is true or false even if the expression represents a string.
Each expression representing a comparison, returns a numerical value of 1 if the expression is true or 0 if false.
For example 10 = 10 represents a value of 1 whereas 10 = 5 represents a value of 0.
The same logic is applied for string expressions where "abc" = "abc" represents a value of 1 and "abc" = "def" represents a value of 0.
This is very useful in the IF command and also in other expressions.
For example the following code :
|
A$ = "on" If A$ = "on" then pin(4) = 1 Else pin(4) = 0 End if |
Can be replaced by
pin(4) = (a$ = "on")
Basic internal keywords:
IF command :
The IF can have the following syntax :
1) IF expression THEN statement
2) IF expression THEN statement1 ELSE statement 2
3) IF expression THEN
Statements
ELSE
Statements
END IF
Example:
|
IF a > 100 THEN print "a"
IF b <a THEN print "b" ELSE print "a"
IF c > d THEN print "C" print "is greater" ELSE print "D" print "is greater" END IF ' (can also be ENDIF without space between END and IF) |
The AND , OR keywords can be used between the expressions as long as they are in parenthesis.
Example:
IF (a=1) AND (b=2) THEN PRINT "ok"
Or
IF ((a=2) AND (b=3) AND (c = 3)) OR (d=4) THEN PRINT "ok"
The IF can be nested
Example:
|
IF a=2 THEN IF b = 2 THEN IF c = 3 THEN PRINT "ok" END IF END IF END IF |
The “THEN” keyword can eventually be removed, even if this is not recommended.
Example:
IF a > 100 print "a" else print "b"
FOR loop
The FOR loop can have the following syntax :
FOR variable=init_value to end_value [step value]
Statements
NEXT variable
The ‘step’ value can be positive or negative
Example:
FOR i=1 to 5
Print i
NEXT i
Will print 1, 2, 3, 4, 5
FOR i=1 to 3 step 0.5
Print i
NEXT i
Will print 1, 1.5, 2, 2.5, 3
FOR i=3 to 1 step -0.5
Print i
NEXT i
Will print 3, 2.5, 2, 1.5, 1
The command EXIT FOR can be used to exit from the loop at any time:
FOR i=1 to 50
IF i=10 THEN EXIT FOR
Print i
NEXT i
Print "end of loop"
New feature : the variable in the NEXT statement can be omitted.
This means that this program is valid :
FOR i=1 to 5
Print i
NEXT
WHILE WEND loop
The WHILE WEND loop can have the following syntax :
WHILE expression
Statements
WEND
The loop is iterated as long as the expression is true
Example:
i = 0
WHILE i < 3
Print i
i = i + 1
WEND
Will print 0, 1, 2
DO LOOP loop
The DOLOOP can have one of the following 4 syntax :
DO WHILE expression
Statements
LOOP
DO UNTIL expression
Statements
LOOP
DO
Statements
LOOP WHILE expression
DO
Statements
LOOP UNTIL expression
The command EXIT DO can be used to exit from the loop at any time
Example
i = 0
DO
Print i
i = i + 0.5
LOOP UNTIL i >3
Will print 0, 0.5, 1, 1.5, 2, 2.5, 3
i = 0
DO
Print i
i = i + 0.5
IF i > 2 THEN EXIT DO
LOOP UNTIL i >3
Will print 0, 0.5, 1, 1.5, 2
SELECT CASE
The SELECTcan have the following syntax:
SELECT CASE expression
CASE exp1 [,exp2], ... [: Statements]
Statements
CASE exp3 [,exp4], ... [: Statements]
CASEfrom TO to [: Statements]
Statements
CASE ELSE
Statements
END SELECT
Example:
a = 4
SELECT CASE a
CASE 1
PRINT "case 1"
CASE 2 : PRINT "case 2"
CASE 3 : PRINT "case 3" : PRINT "can continue on same line"
CASE 4 : PRINT "case 4"
PRINT "can continue also on next line"
CASE 5, 6 : PRINT "case 5 or 6"
CASE 7 TO 10 : PRINT "case 7 to 10"
CASE ELSE:
PRINT "case else"
END SELECT
GOTO
The GOTOcan have the following syntax :
GOTO [LABEL | LAB$]
Example
a = 5
IF a > 5 THEN GOTO LABEL1
END
....
LABEL1:
PRINT "This is label1"
....
The goto must be considered as an obsolete command and is provided just for backward compatibility with old style Basic programs.
GOSUB
The GOSUBcan have the following syntax :
GOSUB [LABEL | LAB$]
The called function must terminate with the command RETURN
Example
a = 5
IF a > 5 THEN GOSUB LABEL1
END
....
LABEL1:
PRINT "This is label1"
RETURN
DATA
The command DATA is used to store constant information in the program code, and is associated with the command READ. Each DATA-line can contain one or more constants separated by commas. Expressions containing variables will be also evaluated here.
The goal of the DATA is to avoid repetitive variable assignation lines, in particular for arrays.
The DATA values will be read from left to right, beginning with the first line containing a DATA statement. Each time a READ instruction is executed the saved DATA position of the last READ is advanced to the next value. Strings must be written in quotes like string constants. The command RESTORE resets the pointer of the current DATA position, so the next READ will read from the first DATA found from the beginning of the program.
In case READ uses the wrong variable type the error message "Type mismatch" appears while referring to the line number containing the READ statement that triggered the condition.
DATA lines may be scattered throughout the whole program code, but for the sake of clarity they would be better kept together at the beginning of the program.
The DATA can have the following syntax :
DATA const1 [,const2] …..
The constants can be Numerical or String.
Example :
DATA 1, 55.88, "constant", 99
READ A, B, C$, D
PRINT A, B, C$, D
Example without DATA:
dim colors$(5)
colors$(1) = "Red"
colors$(2) = "Green"
colors$(3) = "Blue"
colors$(4) = "Yellow"
colors$(5) = "Magenta"
Same example but using DATA:
DATA "Red", "Green", "Blue", "Yellow", "Magenta"
dim colors$(5)
For i=1 to 5
Read colors$(i)
Next i
END
Define the end of the program. With this command the program stops.
It can also be :
END IF -> close the IF command
END SELECT -> closes the SELECT CASE command
END SUB -> closes the user defined SUB
EXIT
Permit to exit from a loop or a user defined SUB.
The syntax is :
EXIT DO -> exit from a DO loop
EXIT FOR -> exit from a FOR loop
EXIT SUB -> exit from a user defined SUB.
SUB
Define a user-defined subroutine, which the script can use like a command or function.
User-defined subroutines are effectively additional commands, so cannot be used as branch labels.
Permit to create a user defined command with optional parameters.
The syntax is SUB subname[(arg1 [,arg2] …)]
The variables are passed by reference; this means that the arguments, if modified inside the subroutine, will modify the original variable. This can be useful to return values from the subroutine (acting like a function).
It is possible to pass arrays using the syntax array_name().
Using the LOCAL command will permit to define local variables (useful to avoid to modify existing global variables).
Example 1 : routine cube
|
SUB cube(x) PRINT X ^3 END SUB
cube 3 ' will print 27 |
Example 2: routine cube with returning argument
|
SUB cube(x,y) y = x ^3 ' the value is returned using the 2nd argument END SUB
ret = 0 cube 5, ret PRINT ret ' will print 125 |
Example 3: routine with local variables and returning argument
|
SUB left_trim(s$, ret$) LOCAL i i = 1 DO UNTIL i = len(s$) IF mid$(s$, i, 1) <> " " THEN EXIT DO i = i + 1 LOOP ret$ = mid$(s$, i) END SUB
z$ = "" FOR i = 1 to 3 left_trim " remove space from left ", z$ PRINT z$ + "--" NEXT i |
Will print
remove space from left --
remove space from left --
remove space from left --
As you can see in this example, the variable i in the FOR loop is not modified by the LOCAL variable i in the subroutine.
Example 4: pass arrays
|
SUB pass_array(f(), c$()) Dim myArray(10) myArray(0) = 456 Print f(0), c$(0), myArray(0) f(1) = 123 c$(1) = "myText" END SUB
Dim alpha(10) Dim beta$(10) alpha(0) = 456 beta$(0) = "testme" Pass_array alpha(), beta$() Print alpha(1), beta$(1) |
In this example, the array alfa() is passed locally to the array f() and the array beta$() is passed locally to the array c$().
Modifying locally these arrays change the value of the original one as their content is passed by reference.
The array “myArray” will disappear at the end of the SUB
Logical / boolean Operations
As the numerical variables are stored internally as double precision floating number, it is possible to store numbers with a precision equivalent to 32 bits.
Several boolean operators are available to manipulate these numbers..
The first operator is the bit shift; it can be shift left << or shift right >>
This operator permit to shift the number of a specified number of positions to left or right.
Example
A = 1
Print A << 3 ' will print 8
A = 16
Print A >> 2 ' will print 4
The operators AND , OR , XOR are also available :
A = 24
A = 15
Print A AND B ' will print 8
A = 24
A = 15
Print A OR B ' will print 31
A = 24
A = 15
Print A XOR B ' will print 23
The unary operator NOT is also available. It inverts all the bits from 0 to 1:
A = 0
Print Hex$(NOT A) ' will print FFFFFFFF
For a 32 bits number, assuming 4 bytes ABCD where A is the MSB and D the LSB, the bytes can be extracted as follows :
VAR = &h12345678 ' this is a 32 bits variable
D = VAR AND &hFF
C = (VAR >> 8) AND &hFF
B = (VAR >> 16) AND &hFF
A = (VAR >> 24) AND &hFF
For more information, see Bitwise Operators
ERRORS HANDLING
Annex allows to control and manage errors happened during the execution of the code.
This is managed with the command ONERROR.
This command defines the action done when an error occurs and applies to all errors including syntax errors.
It can be used in different ways, as specified in the table below:
|
FUNCTIONS / COMMANDS |
DESCRIPTION |
ONERROR ABORT |
Displays the error message and abort the program. This is the normal behaviour and is the default when a program starts running. |
ONERROR IGNORE |
Any error will be simply ignored. As this can make very difficult to debug a program it should be used wisely. |
ONERROR SKIP [nn] |
Ignore an error in a number of commands (specified by the number 'nn') executed following this command. 'nn' is optional, the default if not specified is one. After the number of commands has completed (with an error or not) the behaviour will revert to ONERROR ABORT. |
ONERROR CLEAR |
Reset the eventual pending error |
ONERROR GOTO [label | OFF] |
Jumps to the error handling routine defined by the label. It can be removed (hence reverting to ONERROR ABORT) replacing the label with OFF. Using RETURN inside the error handling routine will continue the execution on the line following the error. |
When an error occurs, the following constants are available :
|
CONSTANT |
DESCRIPTION |
BAS.ERRLINE |
Returns the line number where the error happened. Value of 0 means no error. It is reset to 0 with the command ONERROR CLEAR or running the program or with the command ONERROR IGNORE or ONERROR SKIP. |
BAS.ERRNUM |
Returns a number where non zero means that there was an error. It is reset to 0 with the command ONERROR CLEAR or running the program or with the command ONERROR IGNORE or ONERROR SKIP. |
BAS.ERRMSG$ |
Return a string representing the error message that would have normally been displayed on the console. It is reset to “No Error” running the program or with the command ONERROR CLEAR or ONERROR IGNORE or ONERROR SKIP. |
Example of error handling using the command ONERROR GOTO :
|
ONERROR GOTO Error_Handler Print "start" Print 3/0 ' this generates a divide by zero error Print space$(60000) ' this generates an out of memory error End
Error_Handler: Print "Error text "; BAS.ErrMsg$ Print "Error num "; BAS.ErrNum Print "Error line "; BAS.ErrLine Return ' returns to the line following the error |
HOW the interpreter works with the HTML code and Objects :
When a client connects to the module using its IP address, the module will redirect automatically to the url ‘/output?menu’, which sends an empty html page present on the module.
That page contains a bunch of javascript code permitting to interface the page with the module using javascript.
This page will automatically open a websocket connection with the module; the "squared led" indicates if the connection was successful (green) or not (red).
A mechanism of ping - pong has been implemented into the javascript in order to hold the connection alive all the time. If the connection is lost, the page will try to reconnect automatically without any manual action.
The button "reconnect" permit to force the reconnection if the automatic reconnection fails.
As soon as the connection is done with the module, the html page is ready to send and receive messages to / from the module.
Initially the page is empty but its content can be easily filled.
To send HTML code to the page, the command HTML is used.
The syntax is : HTML HTML code.
For example the line
HTML "Hello, world <br>This is my first html content<br>"
Will give this result :
Continuing with the HTML command, the content can be improved :
HTML "Textbox: <input type='text'><br>"
Continuing again:
HTML "Button: <button type='button'>Click Here</button>"
All the html code can be combined and sent with just one HTML command; this is much faster:
|
a$ = "Hello, world <br>This is my first html content<br>" a$ = a$ + "Textbox: <input type='text'><br>" a$ = a$ + "Button: <button type='button'>Click Here</button>" HTML a$ |
To clear the content of the page, the command is:
CLS
Now we can try another example
CLS
a$ = "Now style me, please<br>"
a$ = a$ + "Button1: <button id='but1' type='button'>ON</button> "
a$ = a$ + "Button2: <button id='but2' type='button'>OFF</button>"
HTML a$
Now we will try to style the buttons using css.
This can be done using command CSS CSSID$()
For example the line
CSS CSSID$("but1", "background-color: red;")
Will give this result :
Combining with the style for the other button:
a$ = a$ + cssid$("but1", "background-color: red;")
a$ = a$ + cssid$("but2", "background-color: green;")
CSS a$
A set of functions is included to simplify the creation of HTML pages as we will see later, so no need to worry if you are not familiar with writing HTML code.
Now we will mention an important ‘event’ that can be used to automatically fill the content of the page each time a client connects to the module : OnHtmlReload.
This ‘event’ defines a place where the program will jump to as soon as Websocket connection request is accepted.
Let’s clarify with an example :
|
OnHtmlReload Fill_Page ‘will jump to Fill_Page when the page is reloaded gosub Fill_Page 'load the page for the first time Wait ‘pause waiting for the event Fill_Page: ‘place where the page begins to be created CLS a$ = "Now style me, please<br>" a$ = a$ + "Button1: <button id='but1' type='button'>ON</button> " a$ = a$ + "Button2: <button id='but2' type='button'>OFF</button>" HTML a$ a$ = cssid$("but1", "background-color: red;") a$ = a$ + cssid$("but2", "background-color: green;") HTML a$ RETURN |
The result will be:
Now try to play with the button "Reconnect"; you’ll see that, at each time the page reconnects to the module, the HTML content is built and sent again. This ensures that each time a client connects to the module it will receive the correct content. At the same time, if other clients are already connected, the content of all the pages will be refreshed simultaneously. This insures a synchronized content between all the clients.
HTML Objects
As said previously, in order to simplify the creation of HTML pages, there are several functions permitting to generate the html code automatically.
Let’s start with the button.
A button is an object that is used to generate an action each time it is pressed on the web page.
The function is BUTTON$.
Let’s explain with an example:
|
CLS HTML BUTTON$("Button1", jump1)
Wait 'pause waiting for the event
Jump1: PRINT "Clicked on Button1" Return |
The result will be:
Try clicking on the button then checking the result in the terminal console; the message "Clicked on Button1" will be shown at each click.
To style the button, we need to modify the syntax of the BUTTON$ command slightly; in fact we need to add another parameter to give the button an ID:
|
CLS HTML BUTTON$("Button1", jump1, "but1") ' "but1" is the ID
Wait 'pause waiting for the event
Jump1: PRINT "Clicked on Button1" CSS cssid$("but1", "background-color: red;") 'the same ID is used here Return |
Clicking on the button now will change its color to red
Now we can now introduce the LED object. The LED object is a circle that can be filled in red or green depending on the content of a variable. The function is LED$
As usual, let’s start with an example:
|
CLS led = 1 'this is the variable associated with the LED. With 0 the led is red, with 1 the led is green HTML LED$(led) |
The result will be:
Let’s also add a button :
|
CLS led = 0 a$ = BUTTON$("Button1", jump1, "but1") ' "but1" is the ID a$ = a$ + LED$(led) HTML a$
Wait 'pause waiting for the event
Jump1: PRINT "Clicked on Button1" led = 1 - led ' invert the variable REFRESH ' refresh (update) the variables between the code and the html Return |
The result will be:
Clicking on the button will toggle the led between red and green colors.
The command REFRESH permits to update (synchronize) the variables in the code with the corresponding objects variables on the web page. It should be run each time a variable is modified.
The refresh
interval should not be less than 300 milliseconds (otherwise the
module will be too busy).
As a simpler alternative, the command AUTOREFRESH will regularly sync the variables.
The command must be run with the desired refresh timing.
Example
AUTOREFRESH 500 will refresh the variables each 500 milliseconds.
This command does not have the same timing limitation of REFRESH so the timing can be faster.
The example :
|
CLS led = 0 a$ = BUTTON$("Button1", jump1, "but1") ' "but1" is the ID a$ = a$ + LED$(led) HTML a$ AutoRefresh 100 'sync each 100 milliseconds Wait 'pause waiting for the event
Jump1: PRINT "Clicked on Button1" led = 1 - led ' invert the variable
Return |
The result will be the same as the previous example.
Now it’s time to introduce another object; the TEXTBOX with the corresponding function TEXTBOX$.
The TEXTBOX will display a ‘text box’ on the web page which is linked with a variable. When the variable is modified in the code, the TEXTBOX content will be updated on the web page and vice-versa.
This will lets us introduce another ‘event’ : the OnHtmlChange command.
This ‘event’ defines a branch for the program to jump to whenever a variable is modified inside the web page.
As usual, let’s start with an example:
|
CLS text$ = "Change me, please" HTML TEXTBOX$(text$) OnHtmlChange Jump1 'will jump to Jump1 when a variable changes on the web page Wait 'pause waiting for the event
Jump1: Print text$ 'print the content of the variable inside the terminal console Return |
Try now to change the content of the textbox and press "Enter" on the keyboard.
Let’s see the result in the terminal console:
With the concepts already learned you’ll be able to use the other objects using the similar logic.
Refer to the pages below to understand the syntax of each object.
TIMERS
A timer is an "object" that permits the execution of a particular action at regular intervals.
When the given time expires, the normal execution of the program is interrupted and control is passed to the "timer interrupt routine" until the execution of the return command.
Then the program continues from the point where it has been interrupted.
Let’s explain with an example :
|
timer0 1000, mytimer wait
mytimer: wlog "mytimer " + time$ return |
Annex WI-Fi Basic implements 2 timers, Timer0 and Timer1.
The Timer0 has a higher priority against Timer1.
EVENTS
Many of the actions are not executed directly by basic commands but can be executed as asynchronous events.
An "event" is simply an action that can be executed when something happens.
For example, the pin change interrupts is an asynchronous event as it can happen at any time without user control.
In order to manage the events, a list of commands "ONxxxx" is provided. These commands define the place where the normal execution of the program will branch to when the event occurs.
So, when the "event" happens, the interpreter interrupts the normal execution of the code and "jumps" to the location defined by the corresponding command "ONxxx". As soon as the code associated with the "event" is terminated with the command "return", the execution continues from the previous interrupted location.
Button Event
This is a special event that happens every time aBUTTON$ object is clicked in the HTML pages.
When this happens, a special variable HtmlEventButton$ is created containing the name of the button that was clicked.
This is useful to determine the button within a group of buttons.
Let’s see an example:
|
CLS HTML Button$("ON", buttonEvent) + " " + Button$("OFF", buttonEvent) wait
buttonEvent: print "You clicked on "; HtmlEventButton$ return |
OnHtmlChange Event
This event is triggered when an object present in the HTML output page changes its value.
It is useful to make actions when something changes in the HTML Pages.
When this event happens, a special variable HtmlEventVar$ is created containing the name of the variable that changed its value.
This is useful to determine the object that generated the event.
Let’s see an example :
|
CLS text$ = "Change me, please" HTML TEXTBOX$(text$) OnHtmlChange Jump1 'will jump to Jump1 when a variable changes on the web page Wait 'pause waiting for the event
Jump1: Print text$ 'print the content of the variable inside the terminal console Return |
OnHtmlReloadEvent
This event is triggered when a Websocket connection request is accepted.
This can be used to automatically fill the content of the WEB page each time a client connects to the module.
Let’s see an example :
|
CLS OnHtmlReload Fill_Page 'will jump to Fill_Page when the page is reloaded gosub Fill_Page 'load the page for the first time Wait 'pause waiting for the event Fill_Page: 'place where the page begins to be created CLS a$ = "Now style me, please<br>" a$ = a$ + "Button1: <button id='but1' type='button'>ON</button> " a$ = a$ + "Button2: <button id='but2' type='button'>OFF</button>" HTML a$ a$ = cssid$("but1", "background-color: red;") a$ = a$ + cssid$("but2", "background-color: green;") HTML a$ Return |
OnInfrared Event
This event is triggered when a code is received by the infrared receiver.
Refer to chapter INFRARED INTERFACE for more details.
OnSerial Event
This event is triggered when a message is received on the serial port.
Example:
|
print
"Ram Available ";
ramfree |
OnSerial2 Event
This event is triggered when a message is received on the serial port #2.
Example
|
serial2.mode
9600, 2, 5
' set serial port #2 to 9600 pin 2 TX, pin 5
RX |
OnTouch Event
This event is triggered when the TFT screen is touched.
Refer to the chapter TouchScreen for more details.
OnUDP Event
This event is triggered when a UDP message is received.
Example:
|
udp.begin
5001
'set the UDP commmunication using port
5001
print
v$ |
OnWgetAsync Event
This event is triggered when a WgetAsync message is received.
This is associated with the command WGETASYNC.
The goal of the WGETASYNC command is to start a html get request without the module having to wait for the answer.
As the answer is async, this command will define the place where the program execution will continue when the message will be received.
Example:
|
ONWGETASYNC answer_done WGETASYNC("www.fakeresponse.com/api/?sleep=5", 80) For i = 0 to 10000 ' a kind of sleep just to demonstrate that the code continue to run Print i Next i Wait answer_done: Print WGETRESULT$ Return |
OnUrlMessage Event
This event is triggered as soon as a web client requests for a web page with the url composed with http://local_ip/msg?param=value.This kind of request is typically called an AJAX request as it permit to exchange in both directions between the client (the web browser) and the server (the ESP module).
In fact, in the url request, the client can send parameters in the form of couples of "param=value" separated by the character "&". For example, if the client want sent 2 parameters, it can send the following request :
http://local_ip/msg?param1=value1¶m2=value2.
As soon as this message is received by the ESP module, the event OnUrlMessage is triggered; this means that the program will continue from the location defined by the command OnUrlMessage.
As soon as the message is received, the parameters sent by the client can be get with the function UrlMsgGet$ and a message can be sent back to the client with the command UrlMsgReturn.
Let’s see an example :
|
onUrlMessage urlAjax wait
urlAjax: wlog "message received " + UrlMsgGet$("a") + " " + UrlMsgGet$("b") UrlMsgReturn "Message sent back " + time$ print UrlMsgGet$("b"), ramfree return |
Now using another web browser window, let’s type the following url :
http://esp_local_ip/msg?a=10&b=20
As you can see in the following picture, the message is received by the ESP module
At the same time, the client receive the message sent back from the ESP module
If the program is stopped, the module will answer with the message "STOPPED"
Now, let’s see a more complete example :
|
cls ' this is the default value for pwm out R = 512 G = 512 B = 512 pwm(12) = R pwm(15) = G pwm(13) = B ' these are the sliders a$ = "" a$ = a$ + |R <input type="range" id="dimmer_R" oninput="setPWM()" onclick="setPWM()" min="0" max="1023" value="| & str$(R) & |"/><br>| a$ = a$ + |G <input type="range" id="dimmer_G" oninput="setPWM()" onclick="setPWM()" min="0" max="1023" value="| & str$(G) & |"/><br>| a$ = a$ + |B <input type="range" id="dimmer_B" oninput="setPWM()" onclick="setPWM()" min="0" max="1023" value="| & str$(B) & |"/><br>| a$ = a$ + |<input type='text' id="txbox" value='---'>| html a$ 'this is the javascript "AJAX" code fun$ = |function setPWM() {| fun$ = fun$ & |r=_$("dimmer_R").value;| fun$ = fun$ & |g=_$("dimmer_G").value;| fun$ = fun$ & |b=_$("dimmer_B").value;| fun$ = fun$ & |var xmlHttp = new XMLHttpRequest();| fun$ = fun$ & |xmlHttp.open("GET", "msg?r=" + r +"&g=" + g +"&b=" + b, false);| fun$ = fun$ & |xmlHttp.send(null);| fun$ = fun$ & |r = xmlHttp.responseText;| fun$ = fun$ & |_$("txbox").value = r;| fun$ = fun$ & |return r;}|
' this is where the javascript code is inserted into the html jscript fun$
'this is where the prog will jump on slider change onUrlMessage message wait
message: print UrlMsgGet$()
pwm(12) = val(UrlMsgGet$("r")) pwm(15) = val(UrlMsgGet$("g")) pwm(13) = val(UrlMsgGet$("b")) UrlMsgReturn UrlMsgGet$() return |
Open the input page into another window and run the program
If you have a ESP-202, you’ll be able to control the color of the RGB led present on the card.
You’ll see how the exchanges can be fast using AJAX exchanges. This program uses javascript embedded into the code. The javascript works with the function XMLHttpRequest.
A good reference for this function is here AJAX - Send a Request To a Server
OnEspNowMsg Event
This event is triggered when a ESP-NOW message is received.
Example:
|
espnow.begin ' init the ESP-NOW onEspNowMsg message ' set the place where jump in case of message reception wait
message: print "Message Received!" return |
OnEspNowError Event
This event is triggered when a ESP-NOW a transmission error occurs.
This happens, in particular, when the receiver device has not received the message.
|
espnow.begin ' init the ESP-NOW espnow.add_peer "60:01:94:51:D0:7D" ' set the MAC address of the receiver onEspNowError status ' set the place where jump in case of TX error espnow.write "TX message" ' send the message wait
status: print "TX error on "; espnow.error$ ' print the error return |
OnMQTT Event
This event is generated when a MQTT message is received
Example:
|
.... onmqtt mqtt_msg
wait ' receive messages from the server mqtt_msg: print "TOPIC : "; mqtt.topic$ print "MESSAGE: "; mqtt.message$ return |
WiFI CONNECTIONS
At startup, the module tries to connect to the router with the parameters provided in the page “Config”.
If the connection is unsuccessful, it will default to AP (Access Point) mode .
By default, if no parameters are specified into the “Config” page, the module will default to the IP address 192.168.4.1 in AP mode with the SSID composed of ESP(+ mac address).
If the connection is successful, the module will use the IP address defined in the “Config” page or, if not specified, the IP will be given automatically by the Router DHCP server.
As soon as the module is connected to the router, it will reconnect automatically if the connection is lost.
There are several commands / functions available to manage the WIFI.
The first function is WIFI.STATUS that permits to get the status of the connection.
print WIFI.STATUS ’ print 3 if connected, 6 if disconnected
The first useful command is WIFI.CONNECT SSID$, password$ [, BSSID$] [, IP$ , MASK$ [, GATEWAY$]]
This command allows you to connect to any WIFI network (STA mode) overriding the parameters defined into the’ “Config” page. This function is async so the connection is done in background, while the program continues to run.
Is then possible to check the status of the connection using the function WIFI.STATUS
Example :
WIFI.CONNECT "HOMENET", "MyPassword"
print
"connecting"
While
WIFI.STATUS <>
3
Print "."
pause 500
wend
Using the optional parameter BSSID$, will enable the connection to a specific WiFi access point.
The BSSID represents the MAC address of the WiFi access point (the router) and it is defined as 6 bytes in hex format separated by colon, i.e. AA:BB:CC:12:34:56.
For stand alone configuration or for ESP-NOW applications, there is another command that puts the module in AP mode.
This command is WIFI.APMODE SSID$, password$ [, channel] [, IP$ , MASK$]
The result is immediate and the status can be checked using the function WIFI.MODE (see below).
The channel is optional and is 1 by default.
It is eventually possible to control the output power of the module with the command WIFI.POWER pow
WIFI.POWER 5 ’ set the output power at 5 dBm.
The module can also be put in WiFi sleep mode. This mode permits to turn off the WiFi reducing the power requirements of the module; this is very useful for battery oriented applications or for applications where the WiFi is not required.
To put the module in “modem-sleep”, the command to execute is WIFI.SLEEP.
The module will stay in that mode until the execution of the command WIFI.AWAKE.
After this command, the module will reconnect automatically to the router (the command WIFI.CONNECT is not required).
Another function available is WIFI.CHANNEL that shows the current Radio Channel used by the WIFI.
Using the function WIFI.RSSI is it possible to get the intensity of the signal received (RSSI)
It is also possible to scan for the WiFi networks accessible around the module.
This can be done using the command WIFI.SCAN and the function WIFI.NETWORKS(network$).
Example :
WIFI.SCAN
While
WIFI.NETWORKS(A$)
=
-1
Wend
Print
a$
The result will be :
Vodaphone, 00:50:56:C0:00:08, -50, 5
Orange, 00:50:56:C0:32:07, -70, 5
Xxxx, 00:50:56:C0:86:CA,-78, 12
These information represent, in the order :
SSID, BSSID(mac address), RSSI(signal intensity), Channel Radio
The function WIFI.MODE returns the current mode of the WIFI connection as below:
|
VALUE |
MEANING |
|
0 |
The WIFI is in sleep mode |
|
1 |
The WIFI is in STATION mode |
|
2 |
The WIFI is in AP mode |
|
3 |
The WIFI in AP+STA mode |
The WIFI in AP+STA mode can be obtained by configuring the module in AP mode and then using the command WIFI.CONNECT in the program.
Using a “fake” SSID / password (example WIFI.CONNECT "A", "" ) can be used to switch the WIFI into the AP+STA mode. This can be useful for mixed ESP32 / ESP8266 ESP-NOW operations.
Another Wifi related command is OPTION.MAC mac$ that permits to modify the MAC address of the module.
This is very important for the ESP Now functionality.
Example :
OPTION.MAC "AA:BB:CC:DD:EE:FF"
In addition, the functions BAS.SSID$ and BAS.PASSWORD$ returns respectively the login and the password used for the STATION wifi connection.
PROGRAM AUTORUN
If a program is defined to run automatically (“Autorun File” in the config page), the WiFi connection process is slightly different.
If the option “Fast boot” in the config page is selected, the program will be executed immediately and the WiFi will be powered ON after a little delay ( 0.1 sec ).
If the command WIFI.SLEEP is executed during the very beginning of the program ( for example as the first line of the program) the WiFi will be simply disabled without using any power.
This enhances the use of the module in low power applications (i.e. on battery).
The WiFi connection can then be restored later using the commands WIFI.CONNECT or WIFI.APMODE.
If the command WIFI.SLEEP is not executed at the beginning of the program, the WiFi connection will be established by default as described in the previous chapter (WiFI CONNECTIONS).
The function BAS.RESETREASON can be used at the beginning of the program to understand the reasons for the restart of the module enabling it to take the appropriate actions.
RECOVERY MODE
In case of any IP or Autorun problem preventing the module from being accessed, it is possible to temporarily bypass the IP settings of the module and disable the Autorun file by connecting the serial TX and RX pins together (GPIO1 to GPIO3) during the startup phase (power up).
This could happen if, for example, a wrong IP address has been set.
Doing this action when restarting the module will put it in AP mode with the IP address at 192.168.4.1, just like a module that has not been configured.
A message “Recovery Mode” will be printed on the console, but none of the existing files on the module will be modified, including config.ini.
In this mode it will be possible to gain access to the module for changing such correct wrong IP parameters using the configuration page.
When the TX/RX link is removed, the module can be rebooted to the configured settings at next restart.
WATCHDOG TIMER
A watchdog timer (or simply a WDT) is an electronic timer that is used to detect and recover from computer malfunctions. During normal operation, the computer regularly resets the watchdog timer to prevent it from elapsing, or "timing out".
If, due to a hardware fault or program error, the computer fails to reset the watchdog, the timer will elapse and generate a timeout signal. The timeout signal is used to initiate corrective action or actions. The corrective actions typically include placing the computer system in a safe state and restoring normal system operation.
Annex implements a watchdog timer with the command OPTION.WDT timeout_msec.
As soon as the watchdog has been defined, the command OPTION.WDTRESET must be executed regularly within the defined timeout otherwise the module will reset automatically.
At the beginning of the program, It is possible to know if the module has been reset by the WDT using the functionBAS.RESETREASON.
Example:
|
' WDT example select case bas.ResetReason case 0: print "normal startup" case 1: print "hardware WDT" case 2: print "exception reset" case 3: print "software WDT" case 4: print "software restart" case 5: print "wake up from deep sleep" case 6: print "external reset" end select
option.WDT 1000 ' set the WDT at 1 second
print "WDT reset regularly" for z = 1 to 50 print z, pause 100 option.WDTreset next z
print "WDT not reset regularly, so should crash after 1 sec" for z = 1 to 50 print z, pause 100 next z |
DATE - TIME timekeeper
The ESP module normally synchronises its date and time from either of two NTP time servers ("pool.ntp.org" and "time.nist.gov"). Optionally an alternative (eg: intranet) time server can be defined using the [CONFIG] page.
Using these servers the ESP doesn’t require any date/time setting as soon as the timezone is correctly defined into the [CONFIG] page.
The timezone is defined as a string likeCET-1CEST,M3.5.0,M10.5.0/3 that describe how the local time must be managed in terms of time shift and DST (summer / winter time).
A complete list of timezone strings can be found here : https://github.com/nayarsystems/posix_tz_db/blob/master/zones.csv
An internal timekeeper has been included if no time server is available, eg no available internet access.
This timekeeper starts from 01/01/1970 00:00:00 and counts the seconds since the power on of the module.
If internet connection becomes available later, the internal timekeeper will sync its time with the NTP servers.
The time can be sync with the NTP time server at any moment using the command OPTION.NTPSYNC.
This time and date can be manually set using the command SETTIME.
The Syntax is :
SETTIME year, month, day, hours, minutes, seconds
Example
Set the date to 02 September 2017 at 13:58:12
SETTIME 17, 9, 2, 13, 58, 12
The time and date can also be manually synchronised to the computer using the "Time Sync" button in the File Manager window of the computer utility ‘tool’ if it has a websocket connection.
WARNING:
In both cases of manual setting, the time and date will be reset back to 1970 default at next restart of the module, so will require setting again.
For more information about the Time Zones and DST, please consult the following page :
It is also possible to connect an RTC (DS1307 or DS3231) to the module.
See the chapter “RTC Module” for more details.
Unix Time functions
The following functions utilises the time following the “Unix Time Stamp” format :
DATEUNIX(date$), TIMEUNIX(time$), UNIXDATE$(value [,format]), UNIXTIME$(value)
The “Unix Time Stamp” is a way to track time as a running total of seconds.
This count starts at the Unix Epoch on January 1st, 1970 at UTC.
Therefore, the unix time is merely the number of seconds between a particular date and the Unix Epoch.
In synthesys :
- DATEUNIX("01/01/18") returns the number of seconds between the 01/01/1970 and the 01/01/2018 (1514764800)
- TIMEUNIX("12:30:55") returns the number of second since midnight (45055)
- UNIXDATE$("1532773308") returns 28/07/18
- UNIXTIME$(1532773308) returns 10:21:48
SPIFFS File System
Annex includes a SPIFFS file system hosted on the flash memory chip.
It “emulates” a disk file system enabling to save and load files in a transparent way.
Depending on the size of the flash chip, the following free space is available :
|
Flash Chip size |
Free space available |
|
1M |
256 Kb |
|
2M |
1MB |
|
4M |
3MB |
|
8M |
7MB |
|
16M |
15MB |
As the SPIFFS has been designed to be very light in terms of resources, it comes with some limitations :
- First the SPIFFS does not support directories, it just stores a “flat” list of files. But contrary to traditional filesystems, the slash character '/' is allowed in filenames, so the functions that deal with directory listing (e.g. FILE.DIR$("/website")) basically just filter the filenames and keep the ones that start with the requested prefix (/website/). Practically speaking, that makes little difference though.
- Second, there is a limit of 31 chars in total for filenames.
- Combined, that means it is advised to keep file names short and not use deeply nested directories, as the full path of each file (including directories, '/' characters, base name, dot and extension) has to be 31 chars at a maximum. For example, the filename /website/images/bird_thumbnail.jpg is 34 chars and will cause some problems if used, for example in FILE.EXISTS() or in case another file starts with the same first 31 characters.
Warning: That limit is easily reached and if ignored, problems might go unnoticed because no error message will appear at runtime.
All the file related functions share the same prefix FILE. followed by the specific function.
|
FUNCTIONS / COMMANDS |
DESCRIPTION |
Ret = FILE.COPY(filename$, newfile$) |
Copy the file filename$ into the file newfile$ Returns 1 in case of success or 0 if error |
Ret = FILE.DELETE(filename$) |
Delete the file specified by filename$ Returns 1 in case of success or 0 if error |
Ret = FILE.EXISTS(filename$) |
Returns 1 if filename$ exists, otherwise returns 0 |
Ret = FILE.RENAME(oldname$, newname$) |
Rename the file oldname$ to newname$ Returns 1 in case of success or 0 if error |
Ret = FILE.SIZE(filename$) |
Returns the size of the file (in bytes) if the file exist, otherwise returns -1 |
Ret$ = FILE.DIR$(path$) |
Will search for files and return the names of entries found. path$ represents the directory name. The function will return the first entry found. To retrieve subsequent entries use the function with no arguments. ie, FILE.DIR$. The return of an empty string indicates that there are no more entries to retrieve. |
Ret$ = FILE.READ$(filename$, [line_num] | [start, length]) |
Returns the content of the file filename$. Specifying line_num, only the corresponding line is read from the file. If start and length options are specified, the file is read from the start position for length characters, otherwise the complete file is read in one go The line number starts from 1. |
FILE.APPEND filename$, content$ |
Append the content of content$ to the file filename$. If the file does not exist, it will be created. The file can be read back using the function FILE.READ$(filename$) File size is only limited by available SPIFFS memory, but the length of filename$ is limited to 31 characters including folder and "/" separators |
FILE.SAVE filename$, content$ |
Save the content of content$ to the file filename$. The file can be read back using the function FILE.READ$(filename$) File size is only limited by available SPIFFS memory, but the length of filename$ is limited to 31 characters including folder and "/" separators |
Examples:
List all the files in the directory /html
|
d$ = FILE.DIR$("/html") While D$ <> "" wlog d$ d$ = FILE.DIR$ Wend |
File operations
|
file.save "/test.bas", "The quick brown fox " wlog "exists", file.exists("/test.bas") wlog "size", file.size("/test.bas") file.append "/test.bas", "jumps over the lazy dog" wlog "size", file.size("/test.bas") wlog "copy", file.copy("/test.bas", "/AAA.bas") wlog "size", file.size("/AAA.bas") wlog "rename", file.rename("/AAA.bas", "/BBB.bas") wlog "size", file.size("/BBB.bas") wlog "size", file.size("/AAA.bas") wlog "read", file.read$("/test.bas") wlog "delete", file.delete("/BBB.bas") |
I/O BUFFERS
The I/O BUFFER is a functionality that gives the capability to hold and manage binary data.
In short the I/O buffer is a block of RAM memory that can be exchanged as a block or read and written byte per byte. It surpasses the limit of the Strings that cannot hold the character ASCII 0 (NUL).
It has a defined length and can be freely dimensioned and cleared.
It can be used in the code using the IOBUFF keyword and Annex exposes 5 I/O buffers numbered from 0 to 4.
The I/O buffers can have any size within the limits of the free RAM memory available.
The main goal of this functionality is to interface with all the functions that require exchanges using binary data.
In the current implementation it can be used with :
- Files
- Serial Ports
- SPI
- I2C
- UDP
As it is essentially a block of memory, the first command is IOBUFF.DIM(buff_num, size) that defines its size.
buff_num can span from 0 (first buffer) to 4 (last buffer)
size can span from 0 to the maximum RAM memory available
Example:
IOBUFF.DIM(0, 1000) 'dimension the I/O buffer 0 with 1000 bytes
The I/O buffer can be filled with a given set of data directly using the function IOBUFF.DIM
Example:
IOBUFF.DIM(0, 10) = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
IOBUFF.DIM(1, 5) = &h12, &hAA, &h50, &O377, &B10101010
As soon as the buffer is dimensioned, the given amount of RAM is reserved for the buffer.
When not required anymore, it can be removed with the command IOBUFF.DESTROY(buff_num)
Example:
IOBUFF.DESTROY(0) 'remove the buffer releasing the memory reserved
Note : The I/O buffers are automatically destroyed each time the program is run.
It is possible to know the size of the buffer using the function IOBUFF.LEN(buff_num)
Example
Print IOBUFF.LEN(buff_num) 'print the length of the buffer
The I/O buffer can be read byte per byte using the function IOBUFF.READ(buff_num, position)
position can span from 0 (first byte) and the buffer length - 1 (last byte)
Example:
Print IOBUFF.READ(0, 4) 'print the byte 4 from the I/O buffer 0
A = IOBUFF.READ(0, 7) ' read in the variable A the byte 7 from the I/O buffer 0
The I/O buffer can be written byte per byte using the command IOBUFF.WRITE(buff_num, position, value)
position can span from 0 (first byte) and the length - 1 (last byte)
value can span from 0 to 255 (byte)
The I/O buffers communicate with the other modules using the following syntax:
- xxxx.READ_IOBUFF(buff_num)
Receive data in the buffer buff_num
- xxxx.WRITE_IOBUFF(buff_num, start, size)
Transmit (send) data from the buffer buff_num starting from the position ‘start’ for ‘size’ bytes
- xxxx.REPLY_IOBUFF(buff_num, start, size)
Reply to the sender data from the buffer buff_num starting from the position ‘start’ for ‘size’ bytes
Where xxxx can be :
UDP
SERIAL
SERIAL2
FILE
I2C
SPI
Detailed syntax :
UDP.READ_IOBUFF(buff_num)
SERIAL.READ_IOBUFF(buff_num)
SERIAL2.READ_IOBUFF(buff_num)
FILE.READ_IOBUFF(buff_num), filename$ [, position, nb_of_bytes_to_read]
I2C.READ_IOBUFF(buff_num), address, register, nb_of_bytes_to_read
SPI.READ_IOBUFF(buff_num), nb_of_bytes_to_read
UDP.WRITE_IOBUFF(buff_num [, start [, size]]), IP$, port
SERIAL.WRITE_IOBUFF(buff_num [, start [, size]])
SERIAL2.WRITE_IOBUFF(buff_num [, start [, size]])
FILE.SAVE_IOBUFF(buff_num [, start [, size]]), filename$
FILE.WRITE_IOBUFF(buff_num [, start [, size]]), filename$
FILE.APPEND_IOBUFF(buff_num [, start [, size]]), filename$
I2C.WRITE_IOBUFF(buff_num [, start [, size]]), address, register
SPI.WRITE_IOBUFF(buff_num [, start [, size]])
UDP.REPLY_IOBUFF(buff_num [, start [, size]]) [,port]
SPI.REPLY_IOBUFF(buff_num [, start [, size]]), (buff_num_reception)
Read Operations
The IOBUFFER can be used for sending or receiving data.
When used for receiving data, the syntax is always .READ_IOBUFF(buff_num).
When receiving data, it is not necessary to dimension the buffer before as it will be automatically dimensioned depending on the size of the data received. If the buffer was already containing some data, these will be flushed and replaced by the new data.
For example, the following command receive all the data available from the serial port 2 in the buffer 3 :
SERIAL2.READ_IOBUFF(3)
This command receive the data coming from an UDP connection in the buffer 1:
UDP.READ_IOBUFF(1)
Additionally some other arguments may be required.
This command read 512 bytes from the file data.bin starting from the file position 123 in the buffer 0:
FILE.READ_IOBUFF(0), “/data.bin”, 123, 512
This command read 8 bytes from an I2C device with address 63 from the register 19 in the buffer 4 :
I2C.READ_IOBUFF(4), 63, 19, 8
This command read 32 bytes from the SPI bus in the buffer 2 :
SPI.READ_IOBUFF(2), 32
Write Operations
When used for sending data, the syntax is always .WRITE_IOBUFF(buff_num [, start [, size]])
When sending data, it is possible to send the entire buffer or only a part of it.
Specifying the optional arguments start and size it is possible to define the part of the buffer to be sent otherwise, if omitted, the entire buffer will be transferred.
For example, the following command send 10 bytes from the buffer 1 starting from the position 45 to the serial port :
SERIAL.WRITE_IOBUFF(1, 45, 10)
This command send the complete buffer 1 to the serial port 2
SERIAL2.WRITE_IOBUFF(1)
This command send 8 bytes from the buffer 2 starting from the position 128 to the SPI bus
SPI.WRITE_IOBUFF(2, 128, 8)
Additionally some other arguments may be required.
This command send 12 bytes from the buffer 1 starting from the position 64 to the UDP on the address 192.168.1.89 and port 8080 :
UDP.WRITE_IOBUFF(1, 64, 12), “192.168.1.89”, 8080
This command send the entire buffer 2 on the same UDP device :
UDP.WRITE_IOBUFF(2), “192.168.1.89”, 8080
This command write the buffer 1 to the file data.bin
FILE.WRITE_IOBUFF(1), “data.bin”
This command has the same result and is provided for compatibility with the existing syntax
FILE.SAVE_IOBUFF(1), “data.bin”
This command appends 36 bytes from the buffer 0 starting from the position 25 to data.bin
FILE.APPEND_IOBUFF(0, 25, 36), “data.bin”
This command send the buffer 2 to the I2C device with address 63 and register 19 :
I2C.WRITE_IOBUFF(2), 63, 19
The same operation but sending only 4 bytes starting from position 0:
I2C.WRITE_IOBUFF(2, 0, 4), 63, 19
Special operations
The syntax .REPLY_IOBUFF(buff_num [, start [, size]]) defines some kind of special operations.
For example, this command send the buffer 0 back to the UDP message original transmitter :
UDP.REPLY_IOBUFF(0)
This is the equivalent of UDP.REPLY message$
Optionally it is also possible specify part of the buffer and the destination port 5001 as below:
UDP.REPLY_IOBUFF(0, 2, 6), 5001
When used with the SPI bus, it enables it to transmit and receive at the same time.
As this operation requires 2 buffers, both must be specified.
For example, this command send the buffer 0 and receive into the buffer 2:
SPI.REPLY_IOBUFF(0), (2)
This command send 4 bytes from the buffer 0 starting from the position 89 and receive 4 bytes in the buffer 3:
SPI.REPLY_IOBUFF(0, 89, 4), (3)
Advanced operations
Several other functions / commands are available for advanced users.
These enable bit, string and hex operations
conversion from hex string :
IObuff.FromHex(buff_num, var$ [, pos])
var$ must contain a hex string in the form of "aabbcc1235"
pos is the position where the HEX must be included in the buffer (0 by default)
A part of the string can be converted in combination with mid$
conversion from string:
IObuff.FromString(buff_num, var$ [, pos])
var$ must contain a text string in the form of "This is a text string"
pos is the position where the HEX must be included in the buffer (0 by default)
A part of the string can be converted in combination with mid$
conversion to hex string:
A$ =IObuff.ToHex$(buff_num, [, start [, size]])
returns an hex string in the form of "aabbcc1235"
start and size are optional and define the start and length (like MID$ but the 1st byte is 0)
conversion to string:
A$ =IObuff.ToString$(buff_num, [, start [, size]])
returns an hex string in the form of "This is a string"
start and size are optional and define the start and length (like MID$ but the 1st byte is 0)
Bit operations
a =IObuff.bit(buff_num, position, bit)
returns the value of the bit of the byte at the position of the buff_num
returns 0 or 1
IObuff.setbit(buff_num, position, bit)
set the bit of the byte at the position of the buff_num
IObuff.clearbit(buff_num, position, bit)
clear the bit of the byte at the position of the buff_num
IObuff.togglebit(buff_num, position, bit)
toggle the bit of the byte at the position of the buff_num
Buffer copy
IObuff.copy(dest_buff_num [,pos]) , (source_buff_num, [, start [, size]])
Copy the from source_buff to dest_buff
pos is the position where the source must be copied in the source (0 by default)
start and size define what must be copied (have the same meaning as in .WRITE_IOBUFF)
Code examples :
UDP - use the remote controller APP for IOS devices (iphone and Ipad)
|
' I/O buffers example using the RCWController ' available in the IOS app store. ' It uses by default the port 10000 ' The APP sends a block of 10 bytes that ' will be printed in the console on the same line udp.begin 10000
' define the place where jump on message reception onudp received wait
received: ' read the incoming data in the buffer 0 udp.read_iobuff(0) size = iobuff.len(0) print "received "; size; " bytes" for z = 0 to 9 ' read and print 1 byte at the time on the same line print iobuff.read(0, z), next z Print ' print an empty line return |
File read and transfer to the serial port by blocks
|
' I/O BUFFERS example using files ' read a file in blocks of 512 characters ' and send them to the serial port (print) fileName$ = "/data8.txt" block_size = 512 ' size of the block to be read file_size = file.size(fileName$) print "File size "; file_size print file_size for z = 0 to file_size - 1 step block_size file.read_iobuff(0), fileName$, z, block_size ' send the block on the serial port (print) serial.write_iobuff(0) next |
Serial port data logger
|
' I/O BUFFERS example to create a serial data logger ' receive bytes from the serial port and ' write them into the file /mylog.txt ' all the characters will be recorded ' including the ASCII 0 (NUL) filename$ = "/mylog.txt"
' define the place where jump on message reception onserial received wait
received: ' waits for 10 millisec giving time to receive all the data pause 10 ' read the incoming data in the buffer 0 serial.read_iobuff(0) size = iobuff.len(0) print "received "; size; " bytes" ' appends the received data to the file file.append_iobuff(0), filename$ return |
DIGITAL I/O
Pin numbers correspond directly to the ESP8266 GPIO pin numbering.
The function of the pin (input / output) must be defined before using the function PIN.MODE as below :
To define the pin 5 as input :
PIN.MODE 5, INPUT
To define the pin 4 as input with a pullup:
PIN.MODE 4, INPUT, PULLUP
To define the pin 2 as output
PIN.MODE 2, OUTPUT
Although pin numbers can be from 0 to 16, gpio pins 6 to 11 should not be used because they are connected to flash memory chips on most modules. Trying to use these pins as IOs will likely cause the program to crash.
Digital pins 0 to 5 and 12 to 15 can be INPUT, OUTPUT, or INPUT, PULLUP .
Pin 16 can be INPUT, OUTPUT. At startup, all available pins are configured as INPUT.
Pins may also serve other functions, like Serial, I2C, SPI.
These functions are normally activated by the corresponding library.
This diagram shows pin mapping for the popular ESP-12F module.
(*) pins not available.
The value from a pîn can read as below :
A = PIN(5)‘ read from pin GPIO5
The pin value can be set as below
PIN(2)= 0 ‘ set 0 on the pin GPIO2
The pin value (0 or 1) can also be easily toggled by subtracting it from 1 (because 1-0=1 and 1-1=0), eg:
PIN(2)= 1 - PIN(2)‘ toggles the value of GPIO2 pin
As many modules use the NodeMCU pin numbering, please use the table below to find the corresponding reference:
|
NodeMCU and Wemos Pin Reference |
Standard GPIO Reference |
|
D0 |
16 |
|
D1 |
5 |
|
D2 |
4 |
|
D3 |
0 |
|
D4 |
2 |
|
D5 |
14 |
|
D6 |
12 |
|
D7 |
13 |
|
D8 |
15 |
|
D9 |
3 |
|
D10 |
1 |
In order to use the Wemos / NodeMcu references, it could be useful to add this code to create the pin constants at the beginning of the program :
D0=16:D1=5:D2=4:D3=0:D4=2:D5=14:D6=12:D7=13:D8=15:D9=3:D10=1
Then refer to the pin constants as below :
a = PIN(D1)
PIN(D3) = 1
The pins GPIO1 (TXD0) and GPIO3 (RXD0) can be used as normal GPIO pins simply declaring them as input or output using the command PIN.MODE .
However, they can be restored at their normal function using the same command with the keyword SPECIAL :
PIN.MODE 1,
INPUT ' set pin 1 (TX) as input
PIN.MODE 3, OUTPUT ' set pin 3
(RX) as output
PIN.MODE 1, SPECIAL ' restore the pin 1 as (TX)
PIN.MODE 3, SPECIAL ' restore the pin 3 as (RX)
PIN INTERRUPTS
The INTERRUPT command permit to trigger an event when the signal on an input pin changes.
The interrupt is triggered BOTH when the signal goes from LOW to HIGH and HIGH to LOW.
Example:
|
pin.mode
12,
input
' set pin 12 as input |
Analog input
ESP8266 has a single ADC channel available to users. It can be used to read voltage at ADC pin.
To read the voltage applied at the pin, the function ADC can be used as below :
print ADC
The voltage range is 0 ... 1.0V and the corresponding range returned by the function is 0 … 1024.
Some modules (like the NodeMCU) have a voltage divider that modify this range.
In particular, the NodeMCU have a full scale range of 3.3V.
Hardware interfaces:
The ESP8266 contains several H/W interfaces that can be controlled by Annex WI-Fi Basic using specific commands and functions.
PWM
This functionality permits to control the output duty cycle of any pin, acting like an analog output.
The pin can be any available pin and the range of the value can be from 0 to 1023.
To use it, there is no need to configure the pin, the command PWM can be used directly as below:
PWM(12) = 512
To disable PWM :
PWM(12) = 0
The default PWM Frequency is 1000 Hz but can be changed using the command
OPTION.PWMFREQ freq where freq can be any value from 1 Hz to 40000 Hz
NOTE :
The ESP doesn't have hardware PWM, so the implementation is by software.
With one PWM output at 40KHz, the CPU is already rather loaded. The more PWM outputs used, and the higher their frequency, the closer you get to the CPU limits, and the less CPU cycles are available for sketch execution.
TONE
It is possible to generate a tone on any pin using the command PIN.TONE.
The syntax is PIN.TONE pin, freq [, duration]
The pin can be any valid GPIO, the frequency can be between 1 and 5000Hz, the optional parameter duration define the duration of the tone in msec; if not defined the tone will last forever and can be removed using the same command with frequency equal to 0.
Example :
PIN.TONE 14, 1000, 200 ‘ tone of 1000Hz on pin 14 for 200 msec
PIN.TONE 14, 100 ‘ tone of 100Hz non stop
PIN.TONE 14, 0 ‘ clear the tone
SERVO
This functionality exposes the ability to control RC (hobby) servo motors. It support up to 4 servos on any available pin.
While many RC servo motors will accept the 3.3V IO data pin from a ESP8266, most will not be able to run off 3.3v and will require another power source that matches their specifications. Make sure to connect the grounds between the ESP8266 and the servo motor power supply.
Before using it, the servo channel (from 1 to 4) and the pin must be defined.
This can be done using the command SERVO.SETUP id, pin as below :
SERVO.SETUP 1, 12 ' attach the servo #1 to pin GPIO12
SERVO.SETUP 2, 13 ' attach the servo #2 to pin GPIO13
After the definition, the servo can be controlled with the command SERVO value as below:
SERVO 1, 90 ' set the servo 1 at 90°
SERVO 2, 45 ' set the servo 2 at 45°
The value must be within the range from 0 to 180
To detach the servo from the pin, use the command SERVO.SETUP id, OFF as below :
SERVO.SETUP 1, OFF
SERVO.SETUP 2, OFF
COUNTERS
This functionality exposes two counters that permit to count pulses from any input pin.
Each counter can return the frequency of the signal using a timeframe of one second.
Additionally, each counter can also return the time occurred between consecutive pulses (period); this is useful as this will permit to determine the frequency of low frequency signals simply taking its reciprocal
(f = 1 / period).
These counters are not based on H/W but are managed using processor interrupts so the input frequency should be limited to around 10 Khz.
It is possible to define when the pulse is counted (on Rising Edge, on Falling Edge, on Change).
The “on Change” is particularly interesting when associated with low frequency measurement as it will permit to double the number of pulses.
Before using the counters, the input pin must be set as INPUT using the command PIN.MODE.
To start to use the counters, the following command is available:
COUNTER.SETUP cnt, pin [,mode]
where:
‘cnt’ defines which counter (1 or 2)
‘pin’ defines the input pin (can be any valid pin except GPIO16)
‘mode’ can be 1 (rising edge), 2 (falling edge) or 3 (change). If not specified, the mode change is enabled.
Example:
PIN.MODE 12,INPUT ‘defines the pin GPIO12 as INPUT
COUNTER.SETUP 1, 12, 1 ‘ Counter 1 using pin GPIO12, count on Rising Edge
The pulses counted can be read using the function COUNTER.COUNT(cnt).
The frequency can be read using the function COUNTER.FREQ(cnt).
The period between 2 consecutive pulses can be read using the function COUNTER.PERIOD(cnt).
Example:
print COUNTER.COUNT(1) ‘print the pulses counted from the counter 1
print COUNTER.FREQ(1) ‘print the frequency from the counter 1
print COUNTER.PERIOD(1) ‘print the period from the counter 1
FInally the counters can be reset with the command COUNTER.RESET cnt
Example:
COUNTER.RESET 1 ‘ reset the counter 1
PID controllers
A proportional–integral–derivative controller (PID controller. or three-term controller) is a control loop feedback mechanism widely used in industrial control systems and a variety of other applications requiring continuously modulated control. (ref wikipedia)
A PID controller continuously calculates an error value e(t) as the difference between a desired setpoint (SP) and a measured process variable (PV) and applies a correction based on proportional, integral, and derivative terms (denoted P, I, and D respectively), hence the name.
In practical terms it automatically applies accurate and responsive correction to a control function.
An everyday example is the cruise control on a car, where ascending a hill would lower speed if only constant engine power is applied. The controller's PID algorithm restores the measured speed to the desired speed with minimal delay and overshoot, by increasing the power output of the engine.
Annex implements 4 PID controllers that can be used simultaneously for any application.
The commands are :
PIDx.INIT Kp, Ki, Kd
PIDx.SETMODE mode
PIDx.LIMITS min, max
PIDx.PERIOD msec
PIDx.PARAMS Kp, Ki, Kd
The main function is:
Pid_Out = PIDx.COMPUTE(CURR_VALUE, TARGET_VALUE)
PIDx can bePID1, PID2, PID3 or PID4.
The first step is to initialise the PID controller.
This can be done with the command PIDx.INIT Kp, Ki, Kd :
Example:
PID1.INIT 50, 80, 1 'initialise the controller with Kp = 50, Ki = 80 and Kd = 1
Optionally the output limits can be set using the command PIDx.LIMITS min, max.
If not defined the output is limited between 0 and 255
Example:
PID1.LIMITS 0, 1023 ' limits the output between 0 and 1023
Then the sampling period can be defined using the command PIDx.PERIOD msec
If not defined the period is set at 100 msec
Example:
PIDx.PERIOD 50 ' define the period at 50 msec
Finally the main function output = PIDx.COMPUTE(input, setpoint)
Example:
Pid_Out = PID1.COMPUTE(CURR_VALUE, TARGET_VALUE)
This function must be called regularly in a loop; the best is to call it using a timer.
The command PIDx.SETMODE mode can be used to put the loop in manual with PIDx.SETMODE 0.
In this case the PID loop will be stopped and the output value will be frozen.
To restore the auto mode (default), the command is PIDx.SETMODE 1.
At any moment the PID parameters can be changed using the command PIDx.PARAMS Kp, Ki, Kd :
Example:
PID1.PARAMS 30, 80, 10 ' modify the PID parameters with Kp = 30, Ki = 80 and Kd = 10
The following example shows how control the speed of a 3-wire 12V PC fan.
The PID utilise the counter to determine the fans speed controlling it using the PWM.
A little circuit is required to drive the positive side of the FAN.
|
CODE: pid1.bas ' PID Test program ' cicciocb 2019 ' this example controls the speed of a 3-wire PC fan ' using the internal counter as input and the PWM as output
PID1.INIT 1, 5, 0 'init the PID paramters PID1.LIMITS 0, 1023 'the PWM goes up to 1023
pin.mode 12, input, pullup 'GPIO12 is the tach input. Pullup is ON counter.setup 1, 12, 3 ' count changes so the output is doubled cnt_p = 0 ' previous value of the counter target = 50 'the default target speed (hz)
timer0 100, do_pid 'the PID is updated each 100msec onHtmlReload create_web_page gosub create_web_page wait
create_web_page: cls a$ = "PID DEMO PROGRAM<br>" a$ = a$ + "SPEED (Hz) " + textbox$(target) html a$ return
do_pid: ' The frequency is computed at each cycle counting the pulses occurred ' As the cycle is executed each 100msec, the frequency computed ' is 1/10 of the real one cnt = counter.count(1) freq = cnt - cnt_p ' the frequency cnt_p = cnt
'the frequency is doubled and divided by 10 'so the real target is target *2 /10 out = pid1.compute(freq, target *2 /10) 'compute the PID print "pulses ";freq, "freq "; freq *10/2, "pwm out ";out pwm(13) = out return |
I2C BUS
The I²C bus allows the module to connect to I²C devices.
I²C uses only two bidirectional open-drain lines, Serial Data Line (SDA) and Serial Clock Line (SCL), pulled up with resistors (typically 4.7K to 10K).
The I²C has a 7 bit address space permitting, theoretically, to connect up to 126 I/O devices.
The maximal number of nodes is limited by the address space and also by the total bus capacitance of 400 pF, which restricts practical communication distances to a few meters. The relatively high impedance and low noise immunity requires a common ground potential, which again restricts practical use to communication within the same PC board or small system of boards.
The current implementation is master mode @ 100Khz by default.
The SDA and SCL pins can be freely defined using the command I2C.SETUP sda_pin, scl_pin.
For example, to define pins 4(SDA) and 5(SCL) the command is :
I2C.SETUP 4, 5
It is important to provide the correct pullup resistor on these lines; values from 10K to 100K should be appropriate.
The commands available are :
I2C.BEGIN,
I2C.END, I2C.REQFROM, I2C.SETUP, I2C.WRITE
The functions available are :
I2C.LEN, I2C.READ, I2C.END
There are also other advanced functions / commands to simplify exchanges with the i2c bus.
The advanced commands available are :
I2C.READREGARRAY, I2C.WRITEREGBYTE,I2C.WRITEREGARRAY
The advanced functions available are :
I2C.READREGBYTE
As all the devices can have a "not well" determined address, please find here a little i2c scanner program which returns the address of all the devices found connected to the bus
|
'I2C Address Scanner 'print in the console the address of the devices found I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5
for i = 0 to 120 i2c.begin i if i2c.end = 0 then print "found "; i , hex$(i) pause 10 end if next i
end |
PCF8574 Module
This is an example of connection of a module with PCF8574 bought on Ebay at less than 2€
This drawing shows how this module must be connected to the ESP8266.
It provides 8 digital inputs or outputs.
This is an example of code that "drives" this module:
|
I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5 device_address = 32 'set to module i2c address 'Write from 0 to 255 on the module 'Each pin will blink at different frequency For i = 0 to 255 PCF8574_write i Next i
'Read all the inputs 'The result is printed into the serial console ' put all the inputs at pullup state PCF8574_write 255
r = 0 For i = 0 to 1000 PCF8574_read r Print r Next i End
sub PCF8574_write(x) i2c.begin device_address i2c.write x i2c.end end sub
sub PCF8574_read(x) i2c.begin device_address i2c.reqfrom device_address, 1 x = i2c.read i2c.end end sub |
ADS1115 Module
This is another example of a connection of a module with ADS1115 bought on Ebay at less than 2€.
This is a 16 Bit ADC 4 channel Module with Programmable Gain Amplifier.
Because the module already contains two 10K I2C pullups, no external resistors are required
As this device is quite simple to interface, it can be directly driven using a “driver” written in basic.
|
' ADS1115 Driver for Annex ' datasheet http://www.ti.com/lit/ds/symlink/ads1115.pdf ' ADS1115 Registers ADS1115_ADDRESS = &h48 ADS1115_CONV_REG = 0 : ADS1115_CONF_REG = 1 ADS1115_HI_T_REG = 2 : ADS1115_LO_T_REG = 3
dim BUFF_IN(2) ' buffer used for read/write to module i2c.setup 4,5 ' set I2C bus
' Set the ADS1115 with : ' AINp = AIN0 and AINn = AIN1 ' FSR = ±4.096 V ' 16 SPS ADS1115_setup 0, 1, 1
' scale in volt scale = 4.096 / 32768
v = 0 for i = 0 to 100000 ADS1115_read v ' read from the module print v * scale next i
end
'--------------------------------------------------------- ' INPUT MULTIPLEX : ' AINp is the input positive ' AINn is the input negative '0 : AINp = AIN0 and AINn = AIN1 '1 : AINp = AIN0 and AINn = AIN3 '2 : AINp = AIN1 and AINn = AIN3 '3 : AINp = AIN2 and AINn = AIN3 '4 : AINp = AIN0 and AINn = GND '5 : AINp = AIN1 and AINn = GND '6 : AINp = AIN2 and AINn = GND '7 : AINp = AIN3 and AINn = GND
'GAIN '0 : FSR = ±6.144 V '1 : FSR = ±4.096 V '2 : FSR = ±2.048 V '3 : FSR = ±1.024 V '4 : FSR = ±0.512 V '5 : FSR = ±0.256 V '6 : FSR = ±0.256 V '7 : FSR = ±0.256 V
'DATA RATE '0 : 8 SPS '1 : 16 SPS '2 : 32 SPS '3 : 64 SPS '4 : 128 SPS '5 : 250 SPS '6 : 475 SPS '7 : 860 SPS sub ADS1115_setup(inp_mux, gain, rate) local conf conf = (inp_mux << 12) or (gain << 9) or (rate << 5) or 3 ' + disable comp 'use the IO Buffer 0 for writing iobuff.dim(0,2) = (conf and &hff00) >> 8 , conf and &hff i2c.write_iobuff(0), ADS1115_ADDRESS, ADS1115_CONF_REG end sub
sub ADS1115_read(ret) 'use the IO Buffer 0 for reading i2c.read_iobuff(0), ADS1115_ADDRESS, ADS1115_CONV_REG, 2 if iobuff.len(0) = 0 then print "No communication" ret = 0 else ret = iobuff.read(0, 0) << 8 + iobuff.read(0, 1) end if if ret > 32768 then ret = ret - 65536 end sub |
MCP23017 Module
This is another example for connecting an I2C module, an MCP20S17 bought on Ebay at less than 2€.
This module provides 16 GPIO pins that can be used as digital inputs or outputs.
Because the module already contains two 10K I2C pullups, no external resistors are required
As this device is quite simple to interface, it can be directly driven using a “driver” written in basic.
|
' MCP23017 Driver for Annex ' datasheet http://ww1.microchip.com/downloads/en/DeviceDoc/20001952C.pdf I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5 device_address = 32 'set to module i2c address
'MCP23017 internal registers IODIRA = 0 : IODIRB = 1 : IPOLA = 2 : IPOLB = 3 GPINTENA = 4 : GPINTENB = 5 : DEFVALA = 6 : DEFVALB = 7 INTCONA = 8 : INTCONB = 9 : IOCONA = 10 : IOCONB = 11 GPPUA = 12 : GPPUB = 13 : INTFA = 14 : INTFB = 15 INTCAPA = 16 : INTCAPB = 17 : GPIOA = 18 : GPIOB = 19 OLATA = 20 : OLATB = 21
i2C.WriteRegByte device_address, IOCONA, &h08 ' init MCP23S17 with bit HAEN i2C.WriteRegByte device_address, IODIRA, &hFF ' all PORT A pins as input i2C.WriteRegByte device_address, GPPUA, &hff ' set PORT A pullup on all pins i2C.WriteRegByte device_address, IODIRB, &h00 ' all PORT B pins as output
r = 0 for z = 0 to 255 I2C.WriteRegByte device_address, GPIOB, z ' pulse all GPIOB pins r = i2C.ReadRegByte(device_address, GPIOA) ' read all GPIOA pins print r pause 100 next z |
SPI BUS
The SPI bus allows the module to connect to SPI devices.
The Serial Peripheral Interface bus (SPI) is a synchronous serial communication interface used for short distance communication between devices.
SPI devices communicate in full duplex mode using a master-slave architecture where the ESP8266 is the master. The ESP generates the frame for reading and writing.
Multiple slave devices are supported through selection with individual chip select (CS) lines.
The SPI bus utilise four logic signals:
|
SIGNAL |
DESCRIPTION |
I/O PIN |
|
SCLK |
Serial Clock (output from the ESP8266) |
GPIO14 |
|
MISO |
Master Input Slave Output (data input to the ESP8266) |
GPIO12 |
|
MOSI |
Master Output Slave Input (data output from the ESP8266) |
GPIO13 |
|
[1] [2] Chip Select (often active low, output from the ESP8266) |
Any pin, controlled by user program |
The commands available are :
SPI.SETUP speed [,data_mode [, bit_order]]
SPI.SETMODE data_mode
SPI.SETFREQ speed
The functions available are :
ret = SPI.BYTE(byte)
a$ = SPI.STRING$(data$, len)
a$ = SPI.HEX$(datahex$, len)
74HC595 Module
This is an example of connection of a module with 74HC595 bought on Ebay at less than 2€
This drawing shows how this module must be connected to the ESP8266.
It provides 8 digital outputs.
This is an example of code that "drives" this module:
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'Write from 0 to 255 on the module 'Each pin will blink at different frequency
spi.setup 100000 ' set the SPI port at 100KHz pin.mode 16,output ' set the Pin used for CS as output
for i = 0 to 255 M_74HC595 i next i
end
sub M_74HC595(x) pin(16) = 1 'put the CS HIGH r = spi.byte(x) pin(16) = 0 'pulse the CS low then high pin(16) = 1 end sub |
MCP23S17 Module
This is another example of a connection of a module with MCP23S17 bought on Ebay at less than 2€.
This module provides 16 GPIO pins that can be used as digital input or output.
As this device is quite simple to interface, it can be directly driven using a “driver” written in basic.
This is an example using the SPI pins and the GPIO15 as CS signal
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' MCP23S17 Driver for Annex ' datasheet http://ww1.microchip.com/downloads/en/DeviceDoc/20001952C.pdf pin(15) = 1 'the GPIO15 is the CS pin.mode 15, output
spi.setup 1000000
'MCP23S17 SPI address MCP23S17_ADDR = &h40 ' assumes A2, A1, A0 to GND 'MCP23S17 internal registers IODIRA = 0 : IODIRB = 1 : IPOLA = 2 : IPOLB = 3 GPINTENA = 4 : GPINTENB = 5 : DEFVALA = 6 : DEFVALB = 7 INTCONA = 8 : INTCONB = 9 : IOCONA = 10 : IOCONB = 11 GPPUA = 12 : GPPUB = 13 : INTFA = 14 : INTFB = 15 INTCAPA = 16 : INTCAPB = 17 : GPIOA = 18 : GPIOB = 19 OLATA = 20 : OLATB = 21
MCP23S17_WRITE IOCONA, &h08 ' init MCP23S17 with bit HAEN MCP23S17_WRITE IODIRA, &h00 ' all PORT A pins as output MCP23S17_WRITE IODIRB, &hff ' all PORT B pins as input MCP23S17_WRITE GPPUB , &hff ' all PORT B pins as pullup
v = 0 for i = 0 to 255 for z = 0 to 255 MCP23S17_WRITE GPIOA, z ' pulse all GPIOA pins MCP23S17_READ GPIOB, v ' read all GPIOB pins print v next z next i End
' function for read / write the MCP23S17 sub MCP23S17_WRITE(register, value) local a pin(15) = 0 a = SPI.byte(MCP23S17_ADDR) a = SPI.byte(register) a = SPI.byte(value) pin(15) = 1 end sub
sub MCP23S17_READ(register, value) local a pin(15) = 0 a = SPI.byte(MCP23S17_ADDR or 1) a = SPI.byte(register) value = SPI.byte(0) pin(15) = 1 end sub |
LCD DISPLAY USING I2C
An LCD display can be connected to the module using I2C interface.
These displays are very cheap and available on Ebay at less than 4€.
This picture shows an LCD with 4 lines at 20 characters per line.
In general these displays are based on the chip HD44780 and works with a parallel interface.
Because the number of pins available on the ESP module is very limited, there is an additional module (in general sold with the display itself) permitting the connection using the bus I2C.
This picture shows the module (generally soldered in the back of the display) enabling the I2C connection.
These modules are based on the chip PCF8574 and have the following relationship between the display pins and the bits of the PCF8574:
|
PCF8574 BIT |
LCD SIGNAL |
|
PCF8574 BIT |
LCD SIGNAL |
|
BIT 0 |
RS |
|
BIT 4 |
D4 |
|
BIT 1 |
RW |
|
BIT 5 |
D5 |
|
BIT 2 |
E |
|
BIT 6 |
D6 |
|
BIT 3 |
BACKLIGHT |
|
BIT 7 |
D7 |
However, this mapping is managed directly into the ESP module so you don’t need to worry about it.
The only important information is the I2C address of the display which may change depending on the card.
The connection is very simple, just 2 pins for the I2C and the power supply are required.
An important point is that the display must be powered with 5V because it will not work at 3.3 V.
In order to use the LCD, there are 2 steps :
- Initialise the I2C bus
- Init the display
This can be done with the following commands :
I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5
LCD.INIT 63, 20, 4 ‘ init an LCD at address 63 (3F in hex) with 20 characters per line and 4 lines
After these 2 lines, there are 2 additional commands available :
LCD.CLS ‘ clear the screen of the LCD
LCD.PRINT x, y, text$ ‘ print a text on the LCD at the position (x, y)
Example:
|
I2C.SETUP 4, 5 'set I2C port on pins 4 and 5 'init an LCD at address 63 (3F in hex) with 20 characters per line and 4 lines LCD.INIT 63, 20, 4 LCD.CLS ' clear the screen of the LCD 'print a message on the LCD at the first char of the first line LCD.PRINT 1, 1, "HELLO WORLD" |
In addition it is possible to control the backlight of the display using the functions
LCD.OFF ' turns OFF the backlight of the LCD
LCD.ON ' turns ON the backlight of the LCD
The LCD has the capability to hold 8 custom characters identified as the ASCII chars from 0 to 7.
The command LCD.CUSTOM char, array() enables to define these custom characters.
For example, to define the custom char 2 :
dim a(8) = 0, 0, 10, 21, 17, 10, 4, 0 'these are 8 bytes defining the 8 rows
LCD.CUSTOM 2, a() 'set the character 2
LCD.PRINT 1,1, CHR$(2) ' print the char
Finally the command LCD.WRITE char enables to print a single char;
It enables, in particular, to print the character 0 (that is ignored in LCD.PRINT).
For example, this program :
|
I2C.SETUP 4, 5 'set I2C port on pins 4 and 5 'init an LCD at address 63 (3F in hex) with 20 characters per line and 4 lines LCD.INIT 63, 20, 4 LCD.CLS ' clear the screen of the LCD 'print a message on the LCD at the first char of the first line LCD.PRINT 1, 1, "HELLO WORLD" 'Create 8 custom chars dim a(8) = 0, 0, 10, 21, 17, 10, 4, 0 'Heart LCD.CUSTOM 0, a() dim a(8) = 0, 0, 10, 31, 31, 14, 4, 0 'Heart filled LCD.CUSTOM 1, a() dim a(8) = 0, 10, 0, 0, 17, 14, 0, 0 'smile LCD.CUSTOM 2, a() dim a(8) = 0, 10, 0, 0, 14, 17, 0, 0 'sad LCD.CUSTOM 3, a() dim a(8) = 0, 14, 17, 17, 17, 10, 10, 27 'omega LCD.CUSTOM 4, a() dim a(8) = 4, 14, 31, 4, 4, 4, 4, 4 'arrow up LCD.CUSTOM 5, a() dim a(8) = 4, 4, 4, 4, 4, 31, 14, 4 'arrow down LCD.CUSTOM 6, a() dim a(8) = 0, 4, 10, 17, 10, 4, 0, 0 'diamond LCD.CUSTOM 7, a()
LCD.print 1 ,2, "" 'set the cursor on the 2nd line 'Print the 8 custom chars for z = 0 to 7 LCD.WRITE z next z |
Will give this result on the LCD:
The custom characters can be created online using this website https://maxpromer.github.io/LCD-Character-Creator/
For example, the char defined in the image, can be defined in annex as below :
|
dim a(8) = &h04, &h0E, &h1F, &h04, &h04, &h1F &h0E, &h04 LCD.CUSTOM 3, a() |
OLED DISPLAY
An OLED display can be connected to the module using the I2C interface.
These displays are very cheap and available on Ebay at less than 3€.
This picture shows an OLED with 128 x 64 pixels monochrome but the size is only 0.96".
This display is based on the chipset SSD1306
It is also possible to use a display based on the chipset SH1106.
The connection is very simple, just 2 pins for the I2C and the power supply are required.
In order to use the OLED, there are 2 steps :
- Initialise the I2C bus
- Init the display
This can be done with the following commands :
I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5
OLED.INIT orientation 'init with a given orientation (0 = normal, 1 = upside-down)
In case of the display SH1106, the command is
OLED.INIT orientation, 1 'init with a given orientation (0 = normal, 1 = upside-down)
After these 2 lines, there are several commands available :
OLED.CLS, OLED.COLOR, OLED.FONT, OLED.PIXEL, OLED.LINE, OLED.RECT, OLED.CIRCLE, OLED.PRINT, OLED.IMAGE, OLED.REFRESH
The current implementation of the OLED is based on a double buffering; this permit to draw in background on the screen while the current image is still shown. This technique permit to avoid flickering while drawing objects on the screen. The command OLED.REFRESH fmt permit to choose between an automatic refresh (OLED.REFRESH 1) or a manual refresh (OLED.REFRESH 0). By default the refresh is automatic.
When an automatic refresh is set, the image is immediately updated after each drawing command whereas, with the manual refresh, the image is refreshed only when an OLED.REFRESH command is executed.
The OLED.COLOR col defines the color to be used by the different drawing commands. As the display is monochrome, only the color 0 (black) and 1(white) can be defined; an additional color 2 (reverse) permit to draw object that reverse the existing color already present on the screen; useful to draw and clear the same object. By default the color is 1 (white).
The OLED.IMAGE x, y, image$ permit to draw an image on the screen from a file. The file format must be XBM, a kind of ‘C’ source code. This format is not really popular but it is supported by the free tool Gimp.
The command OLED.FONT font_num permits to define the font to be used by the command OLED.PRINT.
There are 4 fonts available, FIXED_5X7, ARIAL MT10, ARIAL MT16, ARIAL MT24.
Example:
|
I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5 OLED.INIT 1 ' init the OLED upside-down OLED.CLS ' clear the screen OLED.FONT 2 OLED.COLOR 1 OLED.PRINT 10,10, "HELLO WORLD" |
ST7920 LCD DISPLAY
An ST7920 LCD display can be connected to the module using the SPI interface.
These displays are very cheap and available on Ebay at less than 5€.
This picture shows an ST7920 with 128 x 64 pixel monochrome.
Some cheap boards will have PSB connected to VDD (5v) This forces the parallel interface to be used. Before you connect your display check that pin 2 (VDD ,5v) and pin 15 (PSB) are not connected. If they are you may need to cut a jumper. Otherwise you will short out your power supply, and the display will not work.
This display is provided with a parallel interface BUT it can be used with a SPI interface, so only 3 pins are required.
As this display use the SPI bus and its speed it is limited at around 1Mb/sec the first command must be:
SPI.INIT 1000000
Then, in order to use the display, it must be initialised.
This can be done with the following command:
ST7920.INIT CS_pin
As per the wiring above, the command is
ST7920.INIT 15
After these 2 lines, there are several commands available :
ST7920.CLS, ST7920.COLOR, ST7920.FONT, ST7920.PIXEL, ST7920.LINE, ST7920.RECT, ST7920.CIRCLE, ST7920.PRINT, ST7920.IMAGE, ST7920.REFRESH
The current implementation of the ST7920 is based on a double buffering; this permits drawing in background on the screen while the current image is still shown. This technique permits to avoid flickering while drawing objects on the screen. The command ST7920.REFRESH fmt permits you to choose between an automatic refresh (ST7920.REFRESH 1) or a manual refresh (ST7920.REFRESH 0). By default the refresh is automatic.
When an automatic refresh is set, the image is immediately updated after each drawing command whereas, with the manual refresh, the image is refreshed only when an ST7920.REFRESH command is executed.
The ST7920.COLOR col defines the color to be used by the different drawing commands. As the display is monochrome, only the color 0 (black) and 1(white) can be defined; an additional color 2 (reverse) permits to draw objects that reverse the existing color already present on the screen; useful to draw and clear the same object. By default the color is 1 (white).
The ST7920.IMAGE x, y, image$ permit to draw an image on the screen from a file. The file format must be XBM, a kind of ‘C’ source code. This format is not really popular but it is supported by the free tool Gimp.
The command ST7920.FONT font_num permits to define the font to be used by the command ST7920.PRINT.
There are 4 fonts available, FIXED_5X7, ARIAL MT10, ARIAL MT16, ARIAL MT24.
Example:
|
SPI.SETUP 1000000 ' set the SPI at 1MB/sec ST7920.INIT 15 ' init the ST7920 with the CS at the pin 15 ST7920.CLS ' clear the screen ST7920.FONT 2 ST7920.COLOR 1 ST7920.PRINT 10,10, "HELLO WORLD" |
RTC module
A module based on chipset DS1307 or DS3231 can be connected to the module using the I2C interface.
These modules are very cheap and available on Ebay at less than 2€.
This picture shows a DS3231 module which is very compact and already contains two 4.7K I2C pullups :
The connection is very simple, just 2 pins for the I2C and the power supply are required.
Available Instructions:
RTC.DATE$[(format)]
RTC.TIME$
RTC.SETTIME Year, Month, Day, Hours, Minutes, Seconds
The use of the RTC module is very simple.
First the I2C must be initialised with the command I2C.SETUP.
Then the date and the time can be read with the string functions RTC.TIME$ and RTC.DATE$.
This time and date can be manually set using the command RTC.SETTIME.
The Syntax is :
RTC.SETTIME Year, Month, Day, Hours, Minutes, Seconds
Example
Set the date to 02 September 2017 at 13:58:12
RTC.SETTIME 17, 9, 2, 13, 58, 12
Example
|
I2C.SETUP 4, 5 ' set I2C port on pins 4 and 5 Print "The date is " + RTC.DATE$ Print "The time is " + RTC.TIME$ |
PCA9685 (PWM / Servo) Module
A PWM / Servo module based on the chip PCA9685 can be connected to the module using the I2C interface.
These modules are very cheap and available on Ebay at less than 2€.
This picture shows a PCA9685 module that makes available up to 16 PWM / Servo outputs.
The PCA9685 is an I²C-bus controlled 16-channel controller optimized for Red/Green/Blue/Amber (RGBA) color backlighting applications. It operates at a programmable frequency from a typical of 24 Hz to 1526 Hz. All outputs share the same PWM frequency.
The duty cycle for each output is adjustable from 0 % to 100 % with 12-bit resolution (4096 steps).
It can also be used to control servo actuators, simply specifying the PWM frequency at 50 Hz.
This module must be connected using I2C and, because it already contains two 10K I2C pullups, no external resistors are required.
Available Instructions:
PCA9685.SETUP address [,freq]
PCA9685.SETFREQ freq
PCA9685.PWM pin, value
In order to use the module, it must be first set with the command PCA9685.SETUP address [,freq]
If not specified, the PWM frequency is set by default at 1000Hz
Then the PWM frequency can be set with the command PCA9685.SETFREQ freq
FInally, the outputs can be driven with the command PCA9685.PWM pin, value
This is an example that drives 2 servos connected on outputs 0 and 1.
|
PCA9685.SETUP &H40, 55 PCA9685.SETFREQ 50 PCA9685.PWM 0, 150 PCA9685.PWM 1, 100
DX = 1 DY = 1 MINX = 100 : MAXX = 500 MINY = 150 : MAXY = 300 X = MINX : Y = MINY
WHILE 1 PCA9685.PWM 0, Y PCA9685.PWM 1, X PAUSE 30 PRINT Y, DY, MAXY X = X + DX Y = Y + DY IF (X < MINX) OR (X > MAXX) THEN DX = - DX IF (Y < MINY) OR (Y > MAXY) THEN DY = - DY WEND END |
TM1637 display module
A display module based on the chipset TM1637 with 4 7-segments display can be connected to the module.
These modules are very cheap and available on Ebay at around 1€.
This picture shows a module with 4 displays at 0.36”.
The following picture shows another module with 4 digits at 0.56”.
The following picture shows another module with 6 digits at 0.56”
Notice that some modules have the “colon” points in the middle, some have the decimal points and some other have 6 digits including the decimal points
The connection is very simple, just 2 pins and the power supply are required.
As the protocol used by this chip is very similar to the I2C, this display can share the same pins used for other I2C devices.
Available Instructions are:
TM1637.SETUP data_pin, clock_pin [, bit_delay] [, display_type]
TM1637.PRINT msg$ [, brightness]
To use it, is very simple.
First initialise the display with the command TM1637.SETUP
With the wiring above, the command must be :
TM1637.SETUP 4, 5
Note that some modules may already include i2c pullup resistors on board (so simply try first without).
It is important to highlight that some display modules may have a capacitor on the input pins.
In that case it will require an extra parameter (bit_delay) at the end of the setup command.
This value can be experimentally found, but a value of 100 should be appropriate for all the modules.
Example : TM1637.SETUP 4, 5, 100
If a “6 digits display” must be connected, another extra parameter (display_type) is required.
Example : TM1637.SETUP 15 16, 100, 1
The display can be used with the command TM1637.PRINT msg$ [, brightness]
Where
msg$ is a text string that contains the message to show
brightness defines the luminosity of the display from 0 (OFF) to 7 (MAX); if omitted the value is 7
All ASCII characters can be used but will be shown within the limitation of the 7 segments of the display.
The decimal point and the colon (:) are automatically managed so, to print 12:34 on the display, simply use
TM1637.PRINT "12:34" or TM1637.PRINT "1.234"
Example
|
TM1637.SETUP 4, 5 For i = 0 to 9999 TM1637.PRINT str$(i), 4 Next i |
TM1638 display module
A display module based on the chipset TM1638 with 8 7-segments display can be connected to the module.
These modules provide 8 LEDs, 8 Digits and 8 Keypad Interface.
These modules are very cheap and available on Ebay at around 2€.
This picture shows a module with 8 digits at 0.36”, 8 leds and 8 buttons
The connection requires 3 pins plus the power supply.
Available Instructions are:
TM1638.BUTTONS
TM1638.PRINT msg$ [, brightness ]
TM1638.SETUP data_pin, clock_pin, strobe_pin
TM1638.LEDS val
To use it, is very simple.
First initialise the display with the command TM1638.SETUP data_pin, clock_pin, strobe_pin
With the wiring above, the command must be :
TM1638.SETUP 4, 5, 15
The display can then be used with the command TM1638.PRINT msg$ [, brightness ]
Where
msg$ is a text string that can contain up to 8 chars ,
brightness defines the luminosity of the display from 0 (OFF) to 15 (MAX); if omitted the value is 15
All ASCII characters can be used but will be shown within the limitation of the 7 segments of the display.
Example
|
TM1638.SETUP 4, 5, 15 For i = 0 to 9999 TM1638.PRINT str$(i) Next i |
As the module contains also 8 leds, it is possible to control them using the command TM1638.LEDS val.
val is a 8 bit number where each bit is associated to a led.
Example
|
TM1638.SETUP 4, 5, 15 For i = 0 to 255 TM1638.LEDS i Next i |
It is also possible to get the status of the buttons with the function TM1638.BUTTONS
Example
|
TM1638.SETUP 4, 5, 15 For i = 0 to 5000 Print TM1638.BUTTONS Next i |
MAX7219 8-Digits 7-segment display
A display module based on the chipset MAX7219 with 8 7-segments display can be connected to the module.
These modules provide 8 Digits 7-segments display including dot points.
These modules are very cheap and available on Ebay at around 2€.
This picture shows a module with 8 digits at 0.36”.
The wiring is done using the SPI bus plus a dedicated CS pin.
Available Instructions are:
MAXDISPLAY.SETUP CS_pin
MAXDISPLAY.PRINT msg$ [,brightness]
To use it, is very simple.
First initialise the display with the command MAXDISPLAY.SETUP CS_pin
With the wiring above, the command must be :
MAXDISPLAY.SETUP 15
The display can then be used with the command MAXDISPLAY.PRINT msg$ [,brightness]
Where
msg$ is a text string that can contains up to 8 chars ,
brightness defines the luminosity of the display from 0 (OFF) to 15 (MAX); if omitted the value is 15
All ASCII characters can be used but will be shown within the limitation of the 7 segments of the display.
Example
|
MAXDISPLAY.SETUP 15 For i = 0 to 9999 MAXDISPLAY.PRINT str$(i) Next i |
MAX7219 Dot Matrix Display
It is also possible to connect dot matrix modules based on the chipset MAX7219.
These modules contain 4 8x8 dot matrix displays each one with a dedicated MAX7219 chip.
These modules can be chained in order to compose a larger display.
The picture shows a module available on Ebay at around 5€.
The wiring is done using the SPI bus plus a dedicated CS pin.
Available Instructions are:
MAXSCROLL.SETUP nb_devices, CS_pin [,reverse]
MAXSCROLL.PRINT msg$
MAXSCROLL.NEXT msg$
MAXSCROLL.TEXT msg$
MAXSCROLL.SHOW position [, brightness]
MAXSCROLL.SCROLL [brightness]
MAXSCROLL.OSCILLATE [brightness]
To use it, the first command required is the setup of the display.
This can be done with the command MAXSCROLL.SETUP nb_devices, CS_pin [,reverse].
The first argument defines the number of 8x8 displays connected; using the module shown above, the number is 4.
The 2nd argument defines the pin used for the CS signal; using the schematic shown above the pin is 15 (GPIO15).
The 3rd argument, if =1, permit to use modules with a reversed order digits.
In our case the command must be :
MAXSCROLL.SETUP 4, 15
The text can then be set on the display with 3 different commands :
1. MAXSCROLL.PRINT msg$
2. MAXSCROLL.NEXT msg$
3. MAXSCROLL.TEXT msg$
The first will set the text that will be shown at the beginning, the 2nd will set the text that will be shown when the first one will be scrolled out of the display and the 3rd will permit to modify immediately the text shown.
For example,
MAXSCROLL.PRINT "Hello"
MAXSCROLL.NEXT "Friend"
Will permit to show “Hello” at the beginning; then as soon as “Hello” is scrolled out of the screen, the text “Friend” will be shown and it will scroll on the display forever until the next execution of the command MAXSCROLL.NEXT msg$
The command MAXSCROLL.TEXT msg$ will permit to modify the text during the scrolling sequence, useful for “dynamic” messages (i.e time/date information).
The command MAXSCROLL.SHOW position [, brightness] will permit to move the text in a given position.
The position 1 if the rightmost line of the display and increasing this value will move the text more on the left.
Optionally is is possible to define the brightness of the display.
The last set of commands is composed of
1. MAXSCROLL.SCROLL [brightness]
2. MAXSCROLL.OSCILLATE [brightness]
The first will permit to scroll the text from the right to the left and, when the text will be completely scrolled out, it will restart again with the same text or, if defined, with the text set with the command MAXSCROLL.NEXT.
The 2nd will permit to scroll the text from the right to the left and, when the text will be completely scrolled out, it will be scrolled back in the opposite direction until it will reach the initial position, then the process will restart again.
These 2 commands have an optional parameter permitting to define the luminosity of the display in a range from 0 (min) to 15 (max); the default value is 0.
As the message requires a continuous scrolling, these commands must be called on a timed interval (using a timer).
Let show with an example using the SCROLL command
|
'Set 4 8x8 displays with GPIO15 as CS pin MAXSCROLL.SETUP 4, 15 'Set the first message as the current time MAXSCROLL.PRINT TIME$ 'Set the second message as the current date MAXSCROLL.NEXT DATE$ 'Set the refresh rate of the display (50 msec) - lower values -> scroll faster TIMER0 50, SCROLLME WAIT
SCROLLME: 'Scroll the display with an intensity of 5 MAXSCROLL.SCROLL 5 RETURN |
This is another example using the OSCILLATE command:
|
'Set 4 8x8 displays with GPIO15 as CS pin MAXSCROLL.SETUP 4, 15 'Set the message MAXSCROLL.PRINT "Hello World" 'Set the refresh rate of the display (50 msec) - lower values -> scroll faster TIMER0 50, SCROLLME WAIT
SCROLLME: 'Oscillate the display with an intensity of 5 MAXSCROLL.OSCILLATE 5 RETURN |
NeoPixel WS2812B led strips
It is possible to connect NeoPixel led strips based on WS2812B Leds.
These strips are generally available in a linear form but also as a circular array.
The wiring is very simple as only one output pin is required for the ESP8266.
This pin must be the pin GPIO2 that is fixed and cannot be changed.
The strips must be supplied at 5V with a dedicated power-supply.
As each led could require up-to 60mA, the power supply must be sized in consequence.
The strip is considered as a sequence of leds where each one has a position and can have a different color.
From a logical point of view, even the circular array is seen as a linear strip with a start and end position.
Then the following commands are available :
NEO.SETUP nb_led
NEO.STRIP led_start_pos, led_end_pos, R, G, B [, disable]
NEO.STRIP led_start_pos, led_end_pos, COLOR [, disable]
NEO.PIXEL led_pos, R, G, B [, disable]
NEO.PIXEL led_pos, COLOR [, disable]
NEO.RGB(R, G, B)
NEO.GETPIXEL(pos)
The first command, NEO.SETUP [nb_led], defines the size (in pîxels) of the led strip.
For example NEO.SETUP 60 defines a strip containing 60 leds (or a ring with 60 leds).
This creates a local memory buffer of the strip line permitting the manipulation of the colors in the background.
Then, the leds of the strips can be addressed taking into account that the first led has the position 0 and the last has the position (nb_led - 1).
For example, using the declaration NEO.SETUP 60, the last led has the position 59.
The leds can then be addressed individually using the command NEO.PIXEL or as a block using the commandNEO.STRIP.
For example, NEO.PIXEL 10, 255, 0, 0 set the led at the position 10 with the color RED and the command NEO.STRIP 20, 30, 0, 0, 255 set the leds at the position 20 through 30 with the color BLUE
The colors can be specified as a sequence of 3 numbers from 0 to 255 representing the intensity for the Red, Green and Blue components or as a single number where the 3 colors are merged together as a whole.
The function NEO.RGB(R, G, B) permits to generate this merged color.
For example, these 3 commands produce the same effect :
NEO.STRIP 0, 10, 0, 255, 0
NEO.STRIP 0, 10, NEO.RGB(0, 255, 0)
NEO.STRIP 0, 10, 65280
The optional argument [, disable] if set to 1, permit to write in memory without refreshing the strip. This is useful to manipulate several leds refreshing the complete line only when required.
For example, with the following program, all the leds will be refresh one by one at 100ms interval :
NEO.SETUP 60
FOR z = 0 TO 59
NEO.PIXEL z, 128
PAUSE 100
NEXT z
But, with the following program, all the leds will be updated in a single shot at the end (after 6 seconds) :
NEO.SETUP 60
FOR z = 0 TO 59
NEO.PIXEL z, 128, 1
PAUSE 100
NEXT z
NEO.PIXEL 59, 128
NeoPixel based WS2812b Dot Matrix DIsplay
It is also possible to connect Dot Matrix modules based on WS2812B Leds.
These modules contain 64 WS2812B leds organised in 8x8 matrix.
Several modules can be chained in order to compose a large display.
The wiring is very simple as only one output pin is required for the ESP8266.
This pin must be the pin GPIO2 that is fixed and cannot be changed.
The modules must be supplied at 5V with a dedicated power-supply.
It must be taken into account that these 8x8 modules can require a lot of current, in particular if all the leds are at max intensity.
As each led could require up-to 60mA, the power supply must be sized in consequence.
From a practical point of view, the displays will never show all the pixels at the same time so we can consider at least 2 amps per display (so 20 amps for 10 displays).
Available Instructions are:
NEOSCROLL.SETUP nb_devices [, serpentine]
NEOSCROLL.PRINT msg$
NEOSCROLL.NEXT msg$
NEOSCROLL.COLORS col$
NEOSCROLL.NEXTCOLORS col$
NEOSCROLL.SHOW pos [, brightness]
NEOSCROLL.TEXT msg$
NEOSCROLL.SCROLL [brightness]
NEOSCROLL.OSCILLATE [brightness]
NEOSCROLL.CLS [refresh]
To use it, the first command required is the setup of the display.
This can be done with the command NEOSCROLL.SETUP nb_devices [, serpentine].
The first argument defines the number of 8x8 modules connected; using the schematic shown above, the number is 4.
The 2nd argument defines if the display itself is arranged in a linear way or as a serpentine.
If it is 0 (default) the normal layout is selected, if is 1, the serpentine layout is chosen.
In our case the command must be :
NEOSCROLL.SETUP 4
The text can then be set on the display with 3 different commands :
4. NEOSCROLL.PRINT msg$
5. NEOSCROLL.NEXT msg$
6. NEOSCROLL.TEXT msg$
The first will set the text that will be shown at the beginning, the 2nd will set the text that will be shown when the first one will be scrolled out of the display and the 3rd will permit to modify immediately the text shown.
For example,
NEOSCROLL.PRINT "Hello"
NEOSCROLL.NEXT "Friend"
Will permit to show “Hello” at the beginning; then as soon as “Hello” is scrolled out of the screen, the text “Friend” will be shown and it will scroll on the display forever until the next execution of the command NEOSCROLL.NEXT msg$
The command NEOSCROLL.TEXT msg$ will permit you to modify the text during the scrolling sequence, useful for “dynamic” messages (i.e time/date information).
As the display permit to show colors, 2 more commands are available:
1. NEOSCROLL.COLORS col$
2. NEOSCROLL.NEXTCOLORS col$
The first defines the colors of the text set with the commandNEOSCROLL.PRINT whilst the 2nd defines the colors of the text set with the command NEOSCROLL.NEXT.
These command NEOSCROLL.COLORS defines the color of each character of the text set with the command NEOSCROLL.PRINT .
The logic is based on a one-to-one correspondence between the text string and the color string.
The color is based on this table :
|
COLOR |
CODE |
|
Blue |
B |
|
Green |
G |
|
Cyan |
C |
|
Red |
R |
|
Magenta |
M |
|
Yellow |
Y |
|
Black |
K |
|
White |
W |
|
White |
Any other char |
For example, the commands
NEOSCROLL.PRINT "Hello"
NEOSCROLL.COLOR "RGBCM"
Will show the string “Hello” where the first character is Red, the 2nd Green, the 3rd Blue, ….
With the same logic, the commands
NEOSCROLL.NEXT "Friend"
NEOSCROLL.NEXTCOLOR "YWRGBM"
Will show the string “Friend” where the first character is Yellow, the 2nd White, the 3rd Red, ….
The command NEOSCROLL.SHOW position [, brightness] will permit to move the text in a given position.
The position 1 if the rightmost line of the display and increasing this value will move the text more on the left.
Optionally is is possible to define the brightness of the display.
The last set of commands is composed of
3. NEOSCROLL.SCROLL [brightness]
4. NEOSCROLL.OSCILLATE [brightness]
The first will permit to scroll the text from the right to the left and, when the text will be completely scrolled out, it will restart again with the same text or, if defined, with the text set with the command NEOSCROLL.NEXT.
The 2nd will permit to scroll the text from the right to the left and, when the text will be completely scrolled out, it will be scrolled back in the opposite direction until it will reach the initial position, then the process will restart again.
These 2 commands have an optional parameter permitting to define the luminosity of the display in a range from 0 (off) to 255 (max); the default value is 5.
Take into account that these displays are very bright so a luminosity of 5 is already enough.
As the message requires a continuous scrolling, these commands must be called on a timed interval (using a timer).
Let show with an example using the SCROLL command
|
'Set 4 WS2812B displays with GPIO2 as input NeoScroll.Setup 4 'Set the first message as the current time NeoScroll.print "TRY Annex WiFi BASIC" NeoScroll.colors "CMYRGCRGBYWRGBCMYRGB"
'Set the next message NeoScroll.next "Hello World!" NeoScroll.nextcolors "BYWRGBCMYRGB"
'Set the refresh rate of the display (30 msec) - lower values -> scroll faster timer0 30, scrollme wait
Scrollme: 'Scroll the display with an intensity of 5 NeoScroll.scroll 5 return |
This is another example using the OSCILLATE command:
|
'Set 4 WS2812B displays with GPIO2 as input NeoScroll.Setup 4 'Set the first message as the current time NeoScroll.print "000" NeoScroll.colors "RBG"
'Set the refresh rate of the display (50 msec) - lower values -> scroll faster timer0 50, scrollme
'Set the counter at 0 v = 0 'Set the incrementing rate timer1 100, increment
wait
Scrollme: 'Scroll the display with an intensity of 5 NeoScroll.oscillate 5 return
increment: v = (v + 1) mod 1000 'increment and limits the value at 999 NeoScroll.text str$(v, "%03f") return |
TFT DISPLAY ILI9341
A TFT Display based on the chipset ILI9341 can be connected to the module using the SPI interface.
These displays are available on Ebay at different sizes from 2.2” to 2.8” and are very cheap.
The resolution of the display is 320 x 240 pixels with 65K colors.
They can also contain a touchscreen controller that permits receiving feedback from the user via the SPI interface.
The model shown below is a 2.8” and contains an interface for the Touch Screen.
As the interface is SPI, the display requires at least 5 pins when connected as a display only and 6 when the touch screen is enabled.
The image below shows an 2.8” display provided with touch screen interface:
These displays have a little jumper zone (J1) that must be solder-bridged if powering the module from 3.3V else it will be configured to work at 5v.
Wiring for display only
Wiring for Display and Touchscreen
In order to use the TFT, the first step is to initialise the Display
This can be done with the following commands :
TFT.INIT 16, 4, 1 ‘ (16 is the pin for CS, 4 is the pin for D/C, 1 is the landscape orientation)
The display is initialized, by default, for a SPI speed of 40 Mhz.
In case of problems (spurious pixels and lines) this can be changed using the command SPI.SETUP speed.
Example
SPI.SETUP 20000000 ‘ set the speed at 20 Mhz.
The display can then be cleared with the command
TFT.FILL 0
The display is now ready to receive drawing commands.
The list of commands available is :
TFT.CIRCLE, TFT.LINE, TFT.PRINT, TFT.RECT, TFT.TEXT.COL, TFT.TEXT.POS, TFT.TEXT.SIZE, TFT.BMP
The list of the functions available is:
TFT.RGB
The color is defined as a number between 0 and 65535; this corresponds to the color format named 565 where 5 bits are dedicated to Red, 6 to green and 5 to blue.
The function TFT.RGB permits to specify the R,G,B components as numbers from 0 to 255.
For example the function RGB(255,0,0) defines the color RED and TFT.RGB(0,255,0) defines the color green.
Look at the documentation for the details of each command.
Example :
|
tft.init 16, 4, 1 tft.fill 0 for r = 0 to 30000 step 0.02 d=r/6 s=sin(r)*sin(5*r+d)*140+160 c=cos(r)*sin(5*r+d)*100+120 tft.circle s,c,10,rnd(65535),1 next r |
This is a little pong game given as a TFT example.
It uses an iphone as a remote controller using an UDP connection.
The iphone application is the RCW controller already shown in the I/O buffer chapter
|
' simple pong example using the remote UDP controller ' RCW controller for IOS (ipad and iphone) ' control the paddle with up and down arrow ' the controller must be connected using the port 10000 udp.begin 10000 onudp received ' set the TFT tft.init 16, 4, 3 tft.fill 0 tft.text.size 2 ' text size of the score tft.text.col tft.rgb(0, 255, 0), 0 ' color of the score
speed = 5 ' speed of game. lower is faster dx = 1 dy = 1 x = 100 y = 100 py = 120 py_p = py dp = 0 score = 0
tft.rect 0, py-30, 4, 30, 63488, 1 'paddle while 1 tft.rect x, y, 10, 10, 0, 1 ' clear the ball x = x + dx y = y + dy tft.rect x, y, 10, 10, 65535, 1 'redraw the ball in the new position 'limits the position of the ball if (x <= 0) or (x >= 319) then dx = - dx if (y <= 0) or (y >= 239) then dy = - dy py_p = py py = py + dp
if py_p <> py then if py > py_p then tft.rect 0, py, 4, 1 , 63488, 1 'paddle tft.rect 0, py-31 , 4, 1 , 0, 1 'paddle else tft.rect 0, py+1 , 4, 1 , 0, 1 'paddle tft.rect 0, py-30, 4, 1 , 63488, 1 'paddle end if end if ' limits of the paddle if (py <= 30) or (py >= 239) then dp = 0 pause speed ' determine the speed of the game tft.text.pos 280, 0 tft.print score if (x = 4) then pp = py - y if (pp >=0 ) and (pp < 35 ) then score = score + 1 if (pp < 10) then dy = 1 if (pp > 20) then dy = -1 dx = 1 else tft.rect 0, py-30, 4, 30, 63488, 1 'redraw paddle tft.rect x, y, 10, 10, 0, 1 'clear ball pause 1000 score = 0 'reset the score dx = 1 if rnd(2) = 0 then dy = 1 else dy = -1 y = rnd(239) end if end if wend
received: udp.read_iobuff(0) ' use the byte 1 top detemine the button pushed arrows = iobuff.read(0, 1)
if arrows = 1 then dp = -1 if arrows = 2 then dp = 1 if arrows = 0 then dp = 0 return |
TouchScreen
The touchscreen functionality permits to get the position of the point pressed on the screen.
It is associated with the event OnTouch and the functions TOUCH.X and TOUCH.Y.
The command Touch.Setup defines the pin used for the Touchscreen.
Example:
|
Touch.Setup 15 OnTouch touchme wait
touchme: print "touched", touch.x, touch.y return |
TFT DISPLAY ST7735
A TFT Display based on the chipset ST7735 can be connected to the module using the SPI interface.
These displays are available on Ebay at different sizes and are very cheap.
The resolution is variable in function of the display and is in general available with a resolution going from 80 x 160 to 128 x 160 pixels with 65K colors.
The pictures below shows a 1.8” model with a resolution of 128 x 160 with a RED TAB
The pictures below shows a 1.44” model with a resolution of 128 x 128 with a GREEN TAB
The pictures below shows a 0.96” model with a resolution of 80 x 160
These displays may have a little jumper zone (J1) that must be solder-bridged if powering the module from 3.3V else it will be configured to work at 5v.
This display can be controlled using the same commands as for the ILI9341 except for the initialisation command TFT.INIT that has specific parameters:
TFT.INIT CS_PIN, DC_PIN, Orientation, Display_width, Display_height, Variant
CS_PIN defines the pin where CS signal is connected
DC_PIN defines the pin where DC signal is connected
Orientation defines the orientation of the display (see table below)
Display_height defines the height (in pixels) of the display in portrait orientation
Display_width defines the height (in pixels) of the display in portrait orientation
Variant defines the variant of the display (see text below)
Variant define the type of display, originally this was based on the colour of the tab on the screen protector film but this is not always true, so try out the different options below if the screen does not display graphics correctly, e.g. colours wrong, mirror images, or tray pixels at the edges.
|
Variant |
Display model |
|
0 |
Green Tab (default) |
|
1 |
Red Tab |
|
2 |
Black Tab |
|
3 |
Green Tab 2 |
|
4 |
Green Tab 3 |
|
5 |
Green Tab 128 x 128 |
|
6 |
Green Tab 80 x 160 |
|
7 |
Red Tab 80 x 160 |
|
8 |
Other |
|
Orientation |
Display model |
|
0 |
Portrait |
|
1 |
Landscape |
|
2 |
Portrait reversed |
|
3 |
Landscape reversed |
The display is initialized, by default, for a SPI speed of 40 Mhz and this is in general too fast for these displays.
In case of problems (spurious pixels and lines) this can be changed using the command SPI.SETUP speed.
Example
SPI.SETUP 20000000 ‘ set the speed at 20 Mhz.
Initialisation examples :
Initialise the first display (1.8” model with a resolution of 128 x 160 with a RED TAB )
TFT.INIT 16, 4, 1, 128, 160, 1
Initialise the 2nd display (1.44” model with a resolution of 128 x 128 with a GREEN TAB )
TFT.INIT 16, 4, 1, 128, 128, 5
Initialise the 3rd display ( 0.96” model with a resolution of 80 x 160 )
TFT.INIT 16, 4, 1, 80, 160, 6
Look at the documentation for the details of each command.
Example :
|
' setup a display 128 x 128 tft.init 16, 4, 1, 128, 128, 5 ' reduce the speed at 20 Mhz Spi.setup 20000000 tft.fill 0 for r = 0 to 30000 step 0.02 d=r/6 s=sin(r)*sin(5*r+d)*50+64 c=cos(r)*sin(5*r+d)*50+64 tft.circle s,c,10,rnd(65535),1 next r |
INFRARED INTERFACE
An infrared receiver can be connected to the module permitting it to decode messages received from RC remote controllers.
It is also possible to connect an IR led permitting to generate RC codes from the module.
This picture shows a kit containing an IR receiver, an IR LED and a controller available on ebay at around 1€.
The following drawing shows an example of connection using the pins GPIO12 and GPIO14:
Details of wiring for the VS1838B
There are several commands associated with the IR functions :
IR.INIT, IR.GET$, IR.SEND and ONINFRARED.
In order to use the Infrared functions, the first command to use is IR.INIT.
This command defines the pins to be used for the IR receiver and the IR transmitter.
As per the wiring given above, the command must be:
IR.INIT 14, 12
IMPORTANT : the pin 16 cannot be used!
The command ONINFRARED defines the label where the program will jump when a code is received by the Infrared receiver. Then, using the function IR.GET$ it will be possible to retrieve the code of the message received:
Example
|
IR.INIT 14, 12 ONINFRARED irReceived Wait
irReceived: PRINT IR.GET$ RETURN |
The transmission can be done using the command IR.SEND:
The format is IR.SEND format, code$, bits
Example for a NEC code:
IR.SEND 3, "20DF40BF", 32
The following formats are supported for the reception and the transmission :
|
VALUE |
FORMAT |
|
-1 |
UNKNOWN |
|
0 |
UNUSED |
|
1 |
RC5 |
|
2 |
RC6 |
|
3 |
NEC |
|
4 |
SONY |
|
5 |
PANASONIC |
|
6 |
JVC |
|
7 |
SAMSUNG |
This is an example working with the RC controller shown in the picture above.
It shows the status of the button 1 to 8 pressed on the web page and can control 8 leds wired to a PCF8574 using the I2C bus :
|
oninfrared irReceived onHtmlReload mypage l1 = 0: l2 = 0: l3=0: l4=0: l5=0: l6=0: l7=0: l8=0 ir.init 14 i2c.setup 4,5 l = 0 PCF8574_write l
gosub mypage wait
irReceived: print ir.get$, ir.get$(1), ir.get$(2), val("&h" + ir.get$(3)), ir.get$(4), ir.get$(5) code_type = val(ir.get$(1)) address = val(ir.get$(2)) cmd = val("&h" + ir.get$(3)) ' if NEC CODE if code_type = 3 then ' if RC address is 0 if address = 0 then if cmd = 22 then l = l xor 1 if cmd = 25 then l = l xor 2 if cmd = 13 then l = l xor 4 if cmd = 12 then l = l xor 8 if cmd = 24 then l = l xor 16 if cmd = 94 then l = l xor 32 if cmd = 8 then l = l xor 64 if cmd = 28 then l = l xor 128 PCF8574_write l setleds l end if end if return
mypage: cls a$ = "" a$ = a$ + |<h1> TEST OF IR REMOTE CONTROLLER COUPLED<br>| a$ = a$ + | WITH AN I2C PCF8574 AND 8 LEDS</h1>| a$ = a$ + led$(l1) + led$(l2) + led$(l3) + led$(l4) + led$(l5) + led$(l6) + led$(l7) + led$(l8) html a$ return
sub setleds(x) ' set the status for the leds l1 = (x and 1) l2 = (x and 2) l3 = (x and 4) l4 = (x and 8) l5 = (x and 16) l6 = (x and 32) l7 = (x and 64) l8 = (x and 128) refresh end sub
sub PCF8574_write(x) i2c.begin 32 'PCF8574 i2c.write x i2c.end end sub |
ULTRASONIC DISTANCE SENSOR HC-SR04
An Ultrasonic distance sensor HC-SR04 can be connected to the module.
This sensor permits to measure the distance from a target positioned in front in a range going from a minimum of 3 cm to a maximum of 3 meters.
For the connection, it requires 2 pins plus the power supply. (5 Volts).
There is just one function, DISTANCE(pin_trig, pin_echo) that returns the distance from the target in cm.
Example:
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' Measure the distance from the target 2 times / second print "DISTANCE MEASUREMENT" for i = 0 to 1000 print str$(DISTANCE(15,12), "%4f") + "cm" pause 500 next i end |
DHT xx Temperature / Humidity Sensors
A Temperature / Humidity sensor of the DHTxx family can be connected.
The picture below the ones that are actually supported.
These sensors requires a single wire connection like shown below:
To use them, is very simple.
First initialise the sensor with the command DHT.SETUP pin, model
The pin can be any available pin of the device and model can be 11, 21 or 22 (for DHT11, DHT21 or DHT22).
Assuming that we are using the DHT22 on the pin GPIO2, the command must be :
DHT.SETUP 2, 22
Then 3 functions are available :
DHT.TEMP
DHT.HUM
DHT.HEATINDEX
The first returns the value of the temperature in °C
The 2nd returns the value of the Humidity in %
The 3rd returns the value of the heat index in °C
.
Example
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DHT.SETUP 2 ,22 Print "The Temperature is "; DHT.TEMP ; "°C" Print "The Humidity is "; DHT.HUM ; "%" Print "The Heat Index is "; DHT.TEMP ; "°C" |
DS18B20 Temperature Sensors
One or several DS18B20 Temperature sensors can be connected.
The picture below shows the ones that are actually supported.
These Dallas 1-wire sensors use a single wire connection as shown below, allowing multiple sensors to be connected in parallel on the same 1-wire bus from a single gpio pin.
There is just one function available :
TEMPR$(pin_number, [ID])
This function will return the temperature or the ID of the device depending on the parameter ‘ID’ specified.
In the schematic above, to read the 3 temperatures, the example code is :
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Print "The Temperature 1 is ";TEMPR$(2, 1) ; "°C" Print "The Temperature 2 is ";TEMPR$(2, 2) ; "°C" Print "The Temperature 3 is ";TEMPR$(2, 3) ; "°C" |
To read the temperature from a unique device connected, the code is :
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Print "The Temperature is ";TEMPR$(2, 1) ; "°C"
|
It is important to note that, if the ID is not specified, the command will return the Hex address of the device(s) connected.
BNO055 Absolute Orientation Sensor
A BNO055 Absolute Orientation Sensor can be connected to the module using the I2C interface.
This sensor contains 3 accelerometers, 3 gyros and 3 magnetometers BUT also contains an integrated 32 bits controller running Bosch Sensortec sensor fusion software.
This frees the ESP8266 the module from all the calculations related to the implementation of a Fusion algorithm.
This component is quite expensive ( ~10 €) compared to the classic MPU6050, MPU9250, ... but the quality of the internal fusion algo enables to use it without any effort.
Before connecting it, the links S0 and S1 must be soldered with the ‘-’ position, as shown in the picture, to enable I2C.
The connection is very simple, just 2 pins for the I2C bus and the power supply are required.
The module is already provided with on-board pull-up resistors, so external pull-up resistors are not required.
Available instructions are :
BNO055.SETUP(address)
BNO055.HEADING
BNO055.PITCH
BNO055.ROLL
BNO055.VECTOR ( param )
BNO055.CALIB [(param)]
The use of the BNO055 module is very simple.
First the I2C must be initialised with the command I2C.SETUP.
Then the module must be initialised with the function BNO055.SETUP(address).
‘address’ must be &h28 if the pin ‘I2C’ is connected to GND or &h29 if connected to VCC.
This function returns 1 if the module has been initialised properly otherwise it returns 0.
After the initialisation, the euler angles can be simply read using the corresponding functions BNO055.HEADING, BNO055.PITCH and BNO055.ROLL
Another useful function is BNO055.CALIB [(param)] that returns the calibration status of the BNO055 internal sensors.
If used without any parameters, it returns 1 when all the internal sensors are calibrated otherwise it returns 0.
The BNO055 is put in auto calibration mode so it will calibrate by itself in background.
Refers to the following link for more information : BNO055 Calibration
Example
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i2c.setup
4, 5
' set I2C port on pins 4 and 5 print "Heading:", bno055.heading print "Calibrated:", bno055.calib
pause 100 |
BME280 Combined humidity and pressure sensor
A BME280 Sensor can be connected to the module using the I2C interface.
This unit combines individual high linearity, high accuracy sensors for pressure, humidity and temperature.
A unit based on the chip BMP280 can also be used, except that this one doesn’t contain the humidity sensor.
The connection is very simple, just 2 pins for the I2C bus and the power supply are required.
The module is already provided with on-board pull-up resistors, so external pull-up resistors are not required.
Available instructions are :
BME280.SETUP(address)
BME280.ALT(qnh)
BME280.HUM
BME280.QFE
BME280.QNH(altitude)
BME280.TEMP
The use of the BME280 module is very simple.
First the I2C must be initialised with the command I2C.SETUP.
Then the module must be initialised with the function BME280.SETUP(address).
‘address’ must be &h76 if the pin ‘SDO’ is connected to GND or &h77 if connected to VCC.
This function returns 1 if the module has been initialised properly otherwise it returns 0.
After the initialisation, the temperature, pressure and humidity can be simply read using the corresponding functions BME280.TEMP, BME280.QFE and BME280.HUM.
The function BME280.ALT(qnh) returns the altitude information but requires, as a parameter, the pressure at sea level.
At the opposite, the function BME280.QNH(altitude) returns the sea level pressure but requires, as a parameter, the current altitude.
Example
|
I2C.SETUP
4,
5 ' set I2C
port on pins 4 and 5 |
APDS9960 Digital Proximity, Ambient Light, RGB and Gesture Sensor
An APDS9960 Sensor can be connected to the module using the I2C interface.
The APDS-9960 device features advanced Gesture detection, Proximity detection, Digital Ambient Light Sense (ALS) and Color Sense (RGBC).
Gesture detection utilizes four directional photodiodes to sense reflected IR energy (sourced by the integrated LED) to convert physical motion information (i.e. direction and distance) to digital information.
The connection is very simple, just 2 pins for the I2C bus and the power supply are required.
The module is already provided with on-board pull-up resistors, so external pull-up resistors are not required.
Available functions are :
APDS9960.SETUP(mode)
APDS9960.READGESTURE
APDS9960.AMBIENT
APDS9960.RED
APDS9960.GREEN
APDS9960.BLUE
APDS9960.PROXIMITY
APDS9960.GESTUREGAIN
APDS9960.GESTURELED
There is also an associated ONGESTURE event.
The use of the APDS9960 module is quite simple.
First the I2C must be initialised with the command I2C.SETUP.
Then the module must be initialised with the function APDS9960.SETUP(mode).
“mode” must be 1 for “GESTURE” mode.
As soon as a gesture is recognised, the event ONGESTURE is triggered, so it then possible to get the recognised gesture with the function APDS9960.READGESTURE
Example
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'APDS9960
GESTURE SENSOR DEMO |