SPI master 0 uses 300uA upon first transfer

RE: SPI master 0 uses 300uA upon first transfer

Stian Røed Hafskjold — Thu, 07 Jun 2018 12:32:13 GMT

Let's continue here https://devzone.nordicsemi.com/f/nordic-q-a/35174/spi-master-0-uses-100ua-after-first-transfer-even-after-workaround

RE: SPI master 0 uses 300uA upon first transfer

Andrew Ong — Thu, 07 Jun 2018 02:55:16 GMT

Actually, this did not completely solve the issue. I still get a average power usage of 113uA that goes away if I never use the SPI.

Using SPI with the "power cycle" workaround

Not using the SPI at all:

I even tried pasting in all the "power cycle" workarounds simultaneously, but it did not fix the phantom 130uA power usage.

spi_master_uninit();
*(volatile uint32_t *)0x40003FFC = 0;
*(volatile uint32_t *)0x40003FFC;
*(volatile uint32_t *)0x40003FFC = 1;

*(volatile uint32_t *)0x40004FFC = 0;
*(volatile uint32_t *)0x40004FFC;
*(volatile uint32_t *)0x40004FFC = 1;

*(volatile uint32_t *)0x40023FFC = 0;
*(volatile uint32_t *)0x40023FFC;
*(volatile uint32_t *)0x40023FFC = 1;

RE: SPI master 0 uses 300uA upon first transfer

Andrew Ong — Wed, 06 Jun 2018 23:06:38 GMT

I looked at that and didn't implement it because it was titled "GPIOTE" instead of SPI. But i did it anyway now that you mentioned it again. For anyone in the future, I used these lines to power cycle the peripheral

*(volatile uint32_t *)0x40003FFC = 0;
*(volatile uint32_t *)0x40003FFC;
*(volatile uint32_t *)0x40003FFC = 1;

RE: SPI master 0 uses 300uA upon first transfer

Stian Røed Hafskjold — Wed, 06 Jun 2018 11:35:04 GMT

Hi, can you try this workaround while uninitializing the SPI? http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.Rev2.errata/dita/errata/nRF52832/Rev2/latest/err_832_new.html

This power cycles the peripheral and the current consumption goes down.