Failed to link AUX passthrough to FMU PWM OUT port of PIXHAWK 4

1

Hi there,

I tried to use RC passthrough set up for FMU PWM OUT(AUX port-2) , but failed.
the autopilot is from holybro, pixhawk 4.
the version of px4 software is 1.12.0dev.
the airframe is Generic Quadcopter x

A. in radio setup of QGroundControl, i assign AUX2 passthrough RC channel to channel 6.
B. in my remote controller, i assign a button to channel 6.
C. my 4 configuration files is as follows:

1)ROMFS/px4fmu_common/init.d/airframes/4001_quad_x:

. ${R}etc/init.d/rc.mc_defaults
set MIXER quad_x
set PWM_OUT 123456

2)ROMFS/px4fmu_common/init.d/rc.mc_defaults:

set MIXER_AUX pass
set PWM_AUX_OUT 1234

3)ROMFS/px4fmu_common/mixers/quad_x.main.mix:

R: 4x
AUX1 Passthrough
M: 1
S: 3 5 10000 10000 0 -10000 10000
AUX2 Passthrough
M: 1
S: 3 6 10000 10000 0 -10000 10000
Z:
Z:

4)ROMFS/px4fmu_common/mixers/pass.aux.mix:

M: 1
S: 3 5 10000 10000 0 -10000 10000
M: 1
S: 3 6 10000 10000 0 -10000 10000
M: 1
S: 3 7 10000 10000 0 -10000 10000
M: 1
S: 3 4 10000 10000 0 -10000 10000

D. first ARMed the vehicle, then, I switched the button of my RC back and forth, and test the output of AUX-2 port(FMU PWM OUT). There are NO responses !!!

E. By the way, the MAIN - 6 port is good.

Anything wrong ? Please give me a help. Thank you very much.

2

have you sloved the problem?

3

Hi, I recently ran into this problem. My understanding is that the AUX output assignment is not as straightforward in pixhawk4 as it is in cuav and cube pilots. The pixhawk4 has fmu output ports which should directly work by assigning the passthrough channel but for some reason they dont. when i switched my hardware from pixhawk4 to CUAV v5plus, the new aux mixer got integrated quite easily.