Connect PX4FLOW to QGroundControl

I followed the document PX4FLOW Developer Guide, connected QGroundControl to PIXFLOW finally.

PX4FLOW data output in QGroundControl
PX4FLOW data output in QGroundControl

The picture above is output ofOPTICAL_FLOW.flow_x and flow_y

I have some questions when start:
Q: Connect Pixhawk or PX4FLOW to PC when upload firmware?
A: Connect FX4FLOW to PC using USB

Q:VIDEO_ONLY set to 1, butVideo Downlink in QGroundcontrol can’t show PXFLOW’s video output (use it to adjust focus only)
A:upgrade QGroundcontrol to version 2.2 or up

Qgroundcontrol can't show PX4FLOW video
Qgroundcontrol can’t show PX4FLOW video

Q:What is focus range PX4FLOW?
A:I did a test, the result is 0.4 – 0.8m.
( remark: document recommend to set the focus to 3m, I can do it by adjusting the lens of PX4FLOW )


Q:How to wiring to Pixhawk?
A:Connect PX4FLOW UART3 to Pixhawk’s serial port. Default id TELEM2


Finally I did a outdoor flight test, check here.