Deepsleep hangs system

[Arno]

Hi
Thanks for the advise. It would be useful if it would bring me a bit further.
Updating the Fw to version 1.18.2.r6 did not help me much. I removed the deepsleep board and dowloaded and installed the pycoproc.py file. Now I get the (infamous) Exception: Board not detected: I2C bus error.... Searched the forum for a solution to no avail..
Working on it for 3 hours but still do not have a solution..

[matthew4355]

@robert-hh Good piece of information posted here.

[Arno]

According to the helpdesk pycoproc.py will not work for expansion boards so I am confused....
It would be very helpful if someone can direct me at an example where an expansion board 3.1 is used in combination with deep sleep

[andreas]

@Arno said in Deepsleep hangs system:

It would be very helpful if someone can direct me at an example where an expansion board 3.1 is used in combination with deep sleep

The DeepSleep class referenced above (maybe from pycoproc) is for controlling the complete shutdown on other boards and the deep sleep shield from the early days. At least, this is what I learned.

With or without expansion board, you might want to just invoke machine.deepsleep() these days. However, this will not completely cut the power supply to the device but rather activate the vanilla deep sleep mode of the ESP32 [1].

[1] https://docs.espressif.com/projects/esp-idf/en/v3.2/api-reference/system/sleep_modes.html

[robert-hh]

@andreas The initial poster use sa LoPy board, which has a bug with respect to machine.deepsleep(). The current consumption would not drop. For these board and other early boards Pycom supplies the deep sleep shield, which powers off the board. This function was then integrated into the expansion board 3.x.
So if you use expansion board 3.x, you must not use the deep sleep shield and its library. If you use expansion board 2.1, you have to use the deep sleep shield, at least if you want a low sleep current.

[andreas]

@robert-hh said in Deepsleep hangs system:

For these board and other early boards Pycom supplies the deep sleep shield, which powers off the board. This function was then integrated into the expansion board 3.x.

Thanks again for the thorough information on that topic and for closing the gaps in our knowledge about this. So, I am humbly asking how you would invoke this kind of deep sleep with the expansion board 3.x then?

I figure that if the functionality to achieve a complete power cut is available from the expansion board already, it might well be used by devices other than the LoPy to save even more power than the ESP32-based deep sleep mode invoked through machine.deepsleep().

Sorry if I am getting something wrong here but your answer made me curious.

[robert-hh]

@andreas To have a deep sleep which cuts teh power to the device there are two options:

• yyPy + Deepsleep shield + expansion board 2 (or something else)
• yyPx + one of the newer expansion boards (expansion board 3, pysense, pytrack, pyscan)

The old xxPy devices (WiPy2, LoPy1, SiPy) have a bug in the power regulator, causing the current being too high, when started with machine.deepsleep().
The deep sleep shield and the newer expansion board use different libraries and must not used together. You can imagine the deep sleep shield as the protoype to expansion board 3. It is one of the few devices where the schematics are available. According to that, It is connected to P10, P17 and P28.
So all of that does not help with the posters initial problem.

[Arno]

@robert-hh Thanks for the update. Can you give a link to the libraries to use, the explanation on how to use and the schematics of the expansion boards? especially for the 3.1 expansion board?
It would be of great help to me and others.

[robert-hh]

@Arno There are no schematics published for expansion board 3.x. As far as I understand it, the library to use should be this one: https://github.com/pycom/pycom-libraries/tree/master/lib/pycoproc
I'm not fully sure, because I never got myself an expansion board 3.x. I have a model 2 in the drawer, and use my own base boards with a FT232 chip for desk testing.

[andreas]

Thanks again for your explanations, @robert-hh!

@robert-hh said in Deepsleep hangs system:

I'm not fully sure, because I never got myself an expansion board 3.x.

I never imagined pycoproc could also be used for the regular expansion board 3.x, I always though it was for controlling the PyTrack and PySense boards only.

Now reading that the same hardware functionality available from the latter two as well as the early Deep Sleep Shield might also be available on the expansion board 3.x, we will be more than happy to investigate whether one can put the device into even lower/zero currents.