Kakute F4 serial SBUS servo out jitter

[Johansen (Steve)]

I am trying to use free UART for sbus servo output co control some auxiliary features like headlights etc on freestyle copter with kakute f4. It works to a degree but there is a lot of servo jitter. I am using SD1 sbus to pwm decoder and it work fine from the receiver sbus but jitters a lot from UART (serial 2).
Any help?

[kd0aij (Mark Whitehorn)]

I’m using the 4 channel FrSky sbus-pwm decoder with a Pixracer, and there is no jitter on the pwm outputs. Don’t have an SD1 to test though.

[Johansen (Steve)]

Not likely SD1 to be the only cause, since SD1 works Ok with Rx sbus out. Where do you get sbus out from pixracer? Dedicated sbus out or from serial? I am not familiar with pixracer. Thanks!

[kd0aij (Mark Whitehorn)]

I’m using a serial port on the pixracer:
SERIAL2_PROTOCOL=15

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