UARTE power consumption after shutdown

RE: UARTE power consumption after shutdown

MKJ — Tue, 19 May 2020 15:03:15 GMT

Kenneth

Thank you, this fixes the problem. I'll verify the answer.

Martin

RE: UARTE power consumption after shutdown

Kenneth — Tue, 19 May 2020 07:39:53 GMT

Good point, try this file instead (should have the same api):
https://github.com/NordicSemiconductor/nrfx/blob/v1.8.4/drivers/src/nrfx_uarte.c

RE: UARTE power consumption after shutdown

MKJ — Mon, 18 May 2020 20:50:02 GMT

We're using SDK16 - and I'd rather not download everything - what other files are required aside from this one as just chanign this file doesn't compile

RE: UARTE power consumption after shutdown

Kenneth — Mon, 18 May 2020 18:29:46 GMT

It may also be that the driver uninit() the peripheral in the wrong order (e.g. that peripheral is disabled while there is an on-going reception), this may cause the same symptoms.

For instance you can find in:
https://github.com/NordicSemiconductor/nrfx/blob/master/CHANGELOG.md#210---2020-01-24

"Improved the UARTE driver to consume less current after the driver uninitialization. Now all clocks are disabled properly after uninitialization."

Can you try to download and use the latest nrfx_uarte driver?
https://github.com/NordicSemiconductor/nrfx/blob/a5397bea558fb4b6838081a22d1ee679289d7417/drivers/src/nrfx_uarte.c

RE: UARTE power consumption after shutdown

MKJ — Mon, 18 May 2020 16:39:15 GMT

Kenneth

Thanks - I can't read the chip markings because it is in a module. I did however read the part and build code registers from the debugger:

We are using SDK 16 with Softdevice 140; we are using most of the peripherals: SPI, QSPI, UARTE, TQI,PDM,GPIOTE, NFC, SAADC, WDT.

I had thought that the SDK included a fix for this power thing (by stopping the UART TX and wiating for it to finish) but this does not appear to be enough.

RE: UARTE power consumption after shutdown

Kenneth — Mon, 18 May 2020 15:24:21 GMT

The 3 lines of code you refer to control the power to the peripheral, and simply does a hard reset of the peripheral. It can be used to return the peripheral to the default power-on state. There is no problem to use this after an uninit.

Can you provide the detailed chip marking on the nRF52840 ic you have? Also, which peripherals are you using in your application (e.g. uart#, twi#, gpiote, spi#)?