Using NRF52832 UART to convert incoming UART bit stream to BLE

[Mike]

Hello, Using NRF52832, I need to convert to BLE 19.2 kbits / sec bit stream, received from another processor UART. I need a sample program, which I can adapt to do this. Where can I find it?

[Rodrigo Lorenzo Leal]

If you want to know how to use UART in the NRF52832, you can check the UART example in the peripheral example folder in the SDK

If you want to know how to transmit UART readings via BLE you can check the ble_app_uart example on the ble_peripheral folder example folder in the SDK.

Edit: added links to documentation.

[endnode]

Hi Mike,

I guess you should first ask the question "Can my both BLE peers able to reliably achieve 20kbps?" It isn't unrealistic but still worth some feasibility. Then you can look into nRF5 SDK and Nordic BLE UART service examples aka NUS (depending on which of asymmetric BLE roles you want to play on nRF5x device you choose examples\ble_peripheral\ble_app_uart or examples\ble_central\ble_app_uart_c) as a baseline.

Cheers Jan

[endnode]

Just to illustrate, 19.2kbps means that you will use 20B per GATT MTU (that corresponds to default MTU size 23B) with 6 MTUs per connection interval and at least 50ms connection interval or lower. Yes, this should be OK if you control BLE stack on both sides (e.g. two nRF5x devices) and might be on the boarder line of better Android and iOS devices but you might get serious problems to achieve 6 packets per connection interval and even if device supports it single re-transmission may cause troubles in queuing. Yes, with lower connection interval and/or extended MTU lengths it should be better but still not automatic that you will have that bandwidth (+ be able to maintain it in noisy environment).

[Mike]

My external to NRF52832 processor is transmitting 19.2 kbps bursts every 5mili-seconds. Can this help? How?

[endnode]

Sorry Mike bu that doesn't make sense, you cannot be transmitting speed units per time unit;) How many bytes you really transmit each 5ms? In the end the best will probably be to wire both dev kits together, do quick PoC FW based on the examples I mentioned below and test it in real;)