NRF52 virtual com port over bluetooth

[gnrboy]

I need to make something like this and need that baudrate which are configurated in smartphone BLE app that this value be and on NRF528XX uart baudrate.

For example when I transmit from smartphone "Hello world" via bluetooth on 115200 baud rate that the nrf528XX transmit "Hello world" on his uart with the same baudrate.

Any help will be very usefull. Thank you.

[awneil]

https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v15.3.0/ble_sdk_app_nus_eval.html

As in a USB VCP, the baud rate is only relevant to the wired connection betwween the nRF52832 and the external device - it is irrelevant to the BLE link, and at the smartphone end.

You could either invent your own in-band protocol - so commands are carried with the UART payload - or create some separate out-of-band control protocol.

For the latter, you'd need to define your own Characteristic(s)...

https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial

maybe also a Service:

https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-services-a-beginners-tutorial

[gnrboy]

I need something like profile SPP

[awneil]

There is nothing like that defined for BLE.

So you will have to use something proprietary - like the Nordic UART Service (NUS) linked above.

[gnrboy]

Is that supported on all nrf52/nrf51 series SoC?

[awneil]

It's all just using standard BLE features, so - yes!

But note that nRF51 is not recommended to new BLE designs:

https://devzone.nordicsemi.com/f/nordic-q-a/42960/status-of-nrf51-products/169728#169728