nRF Desktop

[William.wei]

Hi, 

we would like to use nRF Desktop to test throughput and show we can send 20B per ms (from peripheral to central). 

The LLPM sample is not well optimized, while nRF Desktop is good application, hence we would like to do in nRF Desktop (assuming 1x nRF52840DK for gaming mouse, and one for dongle).

In the code, there is an option to spin automatically mouse cursor in circle, or for the simulated keyboard on the DK, we can send "nordic" continously... but how could we make sure that we send always 20Bytes? Is there way to modify the data sent, so that we can send randomly always 20bytes (it can still be HID data, but it must be 20bytes). 

Any suggestion?

thanks

[ovrebekk]

Hi Lorenzo

The difference between 1 byte and 20 is not very large on the overall radio time, the main overhead is in starting the radio, getting an ACK and so forth. 

For HID the packet length and format is set by the HID descriptor, and the keyboard and mouse descriptors are usually around 8-10 bytes long. In order to change this it is possible to modify the HID descriptor, and add some dummy bytes at the end to make the packet 20 bytes long, but you also need to change the code that sends the HID report to make sure you are actually sending the full 20 bytes. 

It won't be a very clear demonstration though. It will look exactly the same to the user, since the additional bytes would just be ignored on the receiving end. 

Best regards
Torbjørn