How to reduce serial port power consumption?

[fomm]

I want to know if enabling serial port flow control can reduce serial port power consumption? Alternatively, using app_uard_close when there is no data transmission can reduce power consumption？I use nrf52832

[Priyanka]

Hi,

When you enable serial port flow control, this can help you to maybe manage, when the UART is active. This can help in reducing the power consumption, because you will only need to keep the UART active when there is data transmission. 

Also, using app_uart_close() can help in reducing power consumption. But by just calling the app_uart_close function, you might not be able to disable the UART. You might also need to set the RX pin as input too after this.

Regards,

Priyanka

[fomm]

Do you mean to set the RX pin of UART to GPIO input for waking up 52832？

Your suggestion seems to be the same as this case：https://devzone.nordicsemi.com/f/nordic-q-a/49220/wakeup-the-nrf51422-with-uart-pins.

But there are some errors in the original case that need to be resolved.

Do you have any detailed suggestions to guide me on how to implement serial port reception on the basis of ble-app_uart_c?I am using SDK 17.0.1. 

[Priyanka]

Hi,

In order to implement serial port reception, you can take a look at the part 2 of the merging two BLE examples blog here.

First the necessary header files are included (app_uart.h and nrf_uart.h). After this, add app_uart_fifo and app_fifo source file to you project and the header file to your include path. Then you can use the uart_init() and uart_event_handle() from the ble_app_uart sample.

Then you can use the uart_rx_enable() function to start receiving.

-Priyanka