time limit for ESP32 sleep command

[Zim]

Is there a maximum time you can specify for sleep? Is 24 hours possible?

Thanks
Zim

[PeterN]

Hi Zim
not shure about the exact number of millis (32bit??) in the hardware counter, but remember that it results in a 71 minutes maximum.
So you may have to wake up x times, read and write a countdown counter into a file and return x-1 times to sleep

[AndyGadget]

Ah yes, that's something I forgot to mention. I'm pretty sure from way back that max asleep is much less than a day. My program would still work as long as you limit the maximum sleep time; it would just wake a few more times.

[PeterN]

Now I remeber where I saw that 71 minutes maximum:
[Local Link Removed for Guests]

[Zim]

Thanks Gents. I found a hardware solution that is adjustable from seconds up to 20 days. I will post my findings if it works.

Thanks
Zim

[cicciocb]

I did a check in the code and It seems that it is actually limited to 32bits (copy paste from the esp8266);
This means that the max time is around 71 minutes (4294 seconds).

However the ESP32 is not limited at 32 bits so it could be possible to remove this limit in a future release

[Zim]

However the ESP32 is not limited at 32 bits so it could be possible to remove this limit in a future release

Wow, that would sure simplify my problem! Would it be possible to slip us a Bin file with this mod? Life would be so much simpler!

Thanks
Zim

[BeanieBots]

When waking from sleep, the RTC RAM is not cleared. Therfore, you could simply increment a counter each sleep period in the non-volatile RAM.
No need to wear out the flash. A wake/read/increment/sleep routine would only keep it awake for a few mS, so no major impact on battery life.
The only downside with sleep periods is that they are +/- 1 brick and temperature sensitive.
Worst I've seen is a 3 minute sleep take 3:12

[cicciocb]

However the ESP32 is not limited at 32 bits so it could be possible to remove this limit in a future release

Wow, that would sure simplify my problem! Would it be possible to slip us a Bin file with this mod? Life would be so much simpler!

Thanks
Zim

Hi,
please find here a version that should fix the sleep command.
Now you should be able to go beyond 71 minutes.
I did not tested ...

This version includes also other stuff not yet documented

Annex32.bin

[Zim]

please find here a version that should fix the sleep command.
Now you should be able to go beyond 71 minutes.
I did not tested ...

This version includes also other stuff not yet documented
Annex32.bin

Thank you! I will test soon.
Zim