BLE Buttonless DFU Template and Serial Library

[Luke Galea]

Hey all,

I am working on the BLE Buttonless DFU Template and I have managed to add the Serial library in Polling mode.

However I am experiencing issues when reading from the UART. Polling mode does not use timeouts and so it is reading one character at a time from the UART line rather than a whole word at a time. The first option would be to fix this.

The second option is to use IRQ or DMA mode, however I am getting the following compilation error: region 'UNPLACED_SECTIONS' overflowed by 40 bytes. and '.nrf_queue' will not fit in region 'UNPLACED_SECTIONS'. Any ideas about this please?

Thanks

[Hung Bui]

Hi Luke, 

If you are not familiar with the nRF5 SDK, I would suggest to get started with other example before starting with BLE Buttonless DFU. 
I don't think using UART in polling mode is a very good idea. It's better to ues IRQ or DMA. You can use our app_uart_fifo library. 

Please refer to our ble_app_uart example, we do IRQ in the example. 

[Luke Galea]

The macro APP_UART_FIFO_INIT is used to initialize a UART instance, what if I need to initialize two UART instances?

[Hung Bui]

Do you plan to have 2 UARTs at the same time ? 
If it's the case, it's not supported out of the box with APP_UART. You need to access serial port directly. 

Have a look here: 

https://devzone.nordicsemi.com/f/nordic-q-a/25173/nrf52840-uart1-not-working-in-sdk-14

and here: 

https://devzone.nordicsemi.com/f/nordic-q-a/19525/how-to-properly-switch-between-uart-pins-and-baud-rates-with-nrf52-uarte#post-id-114413

[Luke Galea]

Hi would you suggest using the UARTE driver then for SDK16? It is more low level I think.

[Hung Bui]

Yes, but it would fit better if you plan to do 2 UARTE at the same time. 

[Luke Galea]

Have you got Driver examples for UART/UARTE in SDK16? Because I managed to find driver examples for other peripherals but not for UART/UARTE. The one example for UART is using FIFO macro which is not aimed for initializing two UART instances.