Low power UART library

[sboudaud]

Hello,

I wanted to ask which uart library we have to use in SDK16 and which configuration to have a LOW POWER UART

We are in development phase on the devkit PCA10040 and our future device will have nRF52810 and SDK16

Thanks by advance.

[bjorn-spockeli]

Hi Stephane, 

I think that the nRF5 SDK v16.0.0: Libuarte - advanced UARTE driver is the best fit for this. Quote from the documentation: 

nrf_libuarte_drv can be configured with hardware events that will start and stop the receiver. This option can be used, for example, to build a low power UART protocol with request and response pins that will enable the receiver only during a transfer. All hardware tasks and events are connected with PPI, which allows autonomous operation that does not depend on the interrupt handling time.

Best regards

Bjørn

[sboudaud]

Thanks Bjorn for the quick reply

[bjorn-spockeli]

Happy to help. 

[Senchoi]

that's strange. Libuarte example reaches 9mA average. How is it going to be used as low power?

[bjorn-spockeli]

9mA is very high. Based on the nRF52832 Product Specification it would seem that the CPU is running, typically ~8mA. The additional 1mA is probably the HFCLK and UART peripheral compounded. So it could sound like there is something that prevents the sample from going to sleep, i.e. WFE or WFI. I suggest you open a new ticket with details on your setup and serial traces if possible.