I'm having an issue similar to the issue Oliver is having. Ground radio can see the air radio and has a solid green light and the red light flashes occasionally. The air unit never seems to connect, has a flashing green light and the red light flashes also in 3 blink bursts. When I first click the connect button I get telemetry data - gps location everything while MavLink is trying to connect. Once it does finally give me the connect failed message I lose everything on the HUD.
I've double and triple checked the wiring. My build info:
AUW is 793g Venom 3s 2200 battery
Arducopter 2.5
Ublox external GPS/Compass plugged into the side GPS port and IC2 port
Telemetry (bought here)
Park 300 1380KV x3
8x4.5 props
2200 mAh 3s Lipo
Turnigy Multistar 15A ESC's
power is over the common rail from the ESC's.
Any thoughts on what to check next? I don't have an FTDI cable to push new firmware. That's on my to order this week list...
Replies
Ok so I finally received the FTDI programmer and the air radio was on a different firmware version from the base radio. Updated both, confirmed all settings match and while plugged into the computer they can talk to each other. Move the air unit back to the APM and same old story: The base radio has solid lights and the air radio flashes the green light slowly and the red light flickers once in awhile.
Getting frustrated....
Check the cabling between the telemetry port and the radio. Also try unplugging the I2C cable and then cycle power to the APM 2.5 and see if that connects. I have a new PixHawk that I finally determined that the I2C port is bad and when I connect the GPS to the Pixhawk I loose communications to the Pixhawk. All the lights look correct but It doesn't communicate. The APM 2.5 MAY behave the same way. Just a guess.
No joy on disconnecting the I2C cable and cycling the APM. Ordered the 3DR PWM module and hoped it was an issue related to pulling the power over the common rail, no such luck. Of course the next step is to try using an FTDI USB Cable to plug in the air module and confirm the settings. If only that cable would come in from China...