BLE and USB communication by using nRF52840 dongle.

Question

Dear all, I started nRF52840 development. Using this module, I'm going to use BLE and USB connection. 
 I have nRF52832 module, which sends BLE data by 1.28Mbps. I'm going to make nRF52840 to receive those data, and send it to PC by USB connection. In summary, nRF52840 is a dongle for PC, BLE receive and USB send. 
 Is there any good example to refer? I think UART doesn't have enough speed for sending data by 1.28Mbps. Thanks everyone, and have a nice day!

ovrebekk · Accepted Answer

Hi 
 I agree wholeheartedly with Andrew in that you should get an nRF52840DK for development. Once you have something working on the DK you can then deploy to the dongle. 
 As for transfer speed this depends more on connection parameters, MTU settings and similar than on the specific service used. As long as you increase the length of the TX and RX characteristics to leverage longer packets there is no reason you can't get high throughput based on the UART service examples. 
 The maximum achievable throughput when using the 2M high speed BLE mode is about 1360kbps, or 1.33Mbps, but please be aware that this assumes zero packet loss. In real life use cases you will typically see lower data rates than this. 
 Gary at Android Authority made a good video demonstrating Bluetooth 5 throughput, and how it can be affected by range and obstructions, based on two nRF52840 DK's: https://www.youtube.com/watch?v=756lbLk3Aqw 
 Skip to the 5 minute mark for the results of his testing. 
 Best regards Torbjørn

awneil · Answer

You will find it far easier to do your development on an nRF52840 Development Kit - rather than on the Dongle. 
 As the name suggests, the Development Kit is specifically designed for doing development - not least because it has a Segger J-Link programmer/debugger built in. 
 juulee said: Is there any good example to refer? 
 because the Dongle is not really intended for development , there are rather few examples for it 
 Another reason why the Development Kit is the better option to start your development! 
 juulee said: I think UART doesn't have enough speed for sending data by 1.28Mbps 
 Note that 1.28Mbps is just the raw radio bit rate - the actual application data throughput achievable in practice will be much less that this. 
 A UART should be fine in association with a BLE link in practice.

BLE and USB communication by using nRF52840 dongle.

Top Replies