micropower/upower.py support for STM32F411

[davefes]

I would like pyb.stop() to woken-up by a trigger signal. C13 has some labels on it RTC_AMP1, RTC_OUT and RTC_TS, however C13 drives a blue LED on the Blackpill. So, maybe I can't use that pin.

The datasheet does not show a WUPP bit so I guess class WakeupPin: is also a non-starter.

Tried changing in class wakeup_X1:

self.pin = pyb.Pin.board.X1
to
self.pin = pyb.Pin.cpu.A0

runs without error, but no wake-up.

[davefes]

I have verified that PWR_CR and the CWUF bit and PWR_CSR and the EWUP bit are the same as for the PYBoard v1.1.

There must be something else in class wakeup_X1 that I have missed or there is something on the hardware platform that is different.

Any suggestions why it might not wake-up?

[davefes]

I have noticed that a 10K pull-up does not lift the low on PA0 at all. Connecting PA0 to 3V3 does bring it up to 3V3 but still no trigger. Also tried C13.

Thought I'd try machine.lightsleep() instead of pyb.stop() and a 10K will pull A0 up ... but still no trigger.

I thought machine.lightsleep and pyb.stop were the same.

[peterhinch]

Have you seen these notes on Pyboard micropower usage? It is definitely possible to wake a Pyboard from pyb.standby deepsleep with the alarm pins. In particular, see para 2.14 which discusses the two tamper pins.

[davefes]

Yes, I have read and am trying to just wakeup the device using pinA0. I had a look at the tamper pin suggestion, but was not certain which were the tamper pin or pins on the STM32F411. I focus more on that method as it seems many STM32 parts have it.

I have tried using C13 so will give class Tamper a try.

self.pin = pyb.Pin.cpu.C13  # X18 doesn't exist on Pyboard D

[davefes]

Ah, C13 sits at about 1.2V and if I pull it down it wakes-up. This looks hopeful.

Thank you.

[davefes]

1.2V is in the "Area not determined", but was HI in my case. Put an external 10K pull-up on C13.

How is def _pinconfig(self): used or when is it run?

[davefes]

Well, thanks Damien for this code snippet machine.lightsleep() or pyb.stop() now can be woken-up. The docs do say you can use a external interrupt!

p = machine.Pin('A0', machine.Pin.IN, machine.Pin.PULL_UP)
p.irq(trigger=machine.Pin.IRQ_RISING, handler=lambda p:None)