Can someone help me find existing code to decode sport telemetry sensor data when connected directly to the sensors?
I currently use a TTL to 3V converter and an SPC (the diode) to connect frsky telemetry sensors directly to my PC's serial port.
I'm seeing the frames that look like
4S 15.21V 3.80 3.80 3.81 3.80
2 messages for 4S lipo sensor
Message: a1:10:0:3 40:6f:d7:76
Message: a1:10:0:3 42:75:07:77
(all messages have the trailing 7e which I stripped and I believe the last byte left above is a checksum)
I can see that telemetry device a1 sends 10:0:2:40 for the first data frame and 10:0:3:42 for the second data frame and then 2x2 bytes encode the level of the 4 cell lipos.
But basically it's painful to reverse engineer the protocol when there must be already decoded somewhere.
I had a look in the opentx code, frsky_sport.cpp, but didn't really find much yet (still looking).
For some reason, also, when I send data from my PC, it doesn't get on the sport bus. Somehow it doesn't get past the diode, so for now, I'm using an X8R plugged into the bus simply to have it send the query to all the sport devices on the bus, and then I read the answers on my PC, but I need to write a real decoder.
To be clear again, I will not be connected to the X8R or to the Taranis X9D, I'm going to be connected directly to the telemetry sensors so that I can read them from an arduino board (pixhawk and/or minimOSD).
Could someone help me a bit with this, especially the decoding part?
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