I have Holybro PX4 and Herelink. About 3 years ago I try to build fixedwing plane but then motors ever start, only beeping. That project I trow to trash because no one cant help. Now I try to build rover but same issue. Motor not start, now it arming fine but nothing happens after that. Can some one post pictures how to do wiring is right…please.
Video work fine and compass, rotation meters etc.
Old Aurdupilot systems works every time but this PX4 is not 
Wirings are now like this.
Herelink UART → PX4 telem1
Herelink SBUS → PX4 Sbus RC
PX4 I/O PWM out → PMB IO PWM in
PX4 power 1 → PMB power 1
PMB motor 1 → rover motor
PMB motor 1 signal → rover motor ESC signal
Rover motor ESC +5/- take power 5v BEC
3s battery PMB power in
Thank you.
(if this not start working these equipment goes to trash 
)