Pixracer and PPM sum

PX4 Autopilot Flight Controllers 💻
1

Hi,

I’ve been trying to connect a PPM sum signal to pixracer to no avail. I connected it accordingly to: http://px4.io/docs/standard-multicopter-configuration/ - the ground and RCin lines.

Basically it reports all the time: discovered 0 channels.

I’ve tested my PPM sum using OrangeRX and it is reported correctly on the transmitter. But pixracer simply does not see it.

It is a regular (not inverted) signal. I also tried an inverted one to the same result.

Is this supposed to work?

Any advice would be appreciated.

Thanks,

2

Out of curiosity I’ve connected my analyzer to the RCin on the Pixracer and this is what I get:

rc_in.png793×577 6.05 KB

I must be missing something or my Pixracer is broken?

3

You should also connect ground

4

I think I got to the bottom of this. It feels like there was a problem with my board - I started to test the RC exclusive-or gate (U1203 74LVC2G86) as I was suspecting something’s wrong with it. I clean it up and it started to work!

Now the pixracer recognizes all the signals but I still need it to recognize an inverted ppm.

Is there a way for pixracer to accept inverted ppm-sum?