New protocol decoder: Avago ADNS-5020

We're happy to announce that libsigrokdecode now supports the adns5020 PD, a decoder for the Avago ADNS-5020 optical mouse sensor protocol.

The decoder was contributed by Karl Palsson, thanks a lot!

It stacks on top of the common SPI PD and decodes ADNS-5020 specific registers reads and writes.

There is an example file in the sigrok-dumps repository if you want to test the decoder, as well as a test config in our sigrok-test repository.