Strange issue with AT+SLEEP

[thomas@novamar.no]

Hi

I am trying to put the mDot unit into sleep mode, however, every time I do, the target MCU (which is an EFM32) freezes and looses connection with the JTAG debugger.

I have connected pao_0 to a GPIO port to be able to wake the device from sleep at a later time. I assume that a short or something happens when the device goes to sleep, because of this pin.

I have tried to have the gpio port on the EFM32 configure as open source, open drain and push pull with the same result all of the times.

Any ideas? I could draw a schematic but really dont see the point because its only a single wire.

The mDot is powered by the 3v output from the MCU.

[thomas@novamar.no]

Hi

I did some testing last night, and apparantly, the MCU is somehow broken, and that is why the short happens. I switched out the MCU, and now I do not loose connection with the debugger when changing the state of the GPIO pin.

However, I see from the datasheet that the dio7 / pao_0 connection does not have pull down or pull up resistors. Does this mean that I have to pull the signal down initially, and pull it up whenever I want to exit sleep?

[thomas@novamar.no]

What does pin 13 on / sleep do?

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