External compass issue

Hi there,
if I connect an external compass via I2C I get a problem.
Without, the firmware can be started.
Does someone know the reason?

Best, Daniel

Problem with:

pi@navio-rpi /usr/bin $ sudo ./ArduCopter-quad
Raspberry Pi 2 with BCM2709!
Raspberry Pi 2 with BCM2709!


Init APM:Copter V3.4-dev (be603da5)

Free RAM: 4096
FW Ver: 120
----------------------------------------


load_all took 299us
0 0 0 ▒ Q}▒▒3▒Calibrating barometer$▒PANIC: AP_Baro::read unsuccessful for more than 500ms in AP_Baro::calibrate [2]

Fine without:

pi@navio-rpi /usr/bin $ sudo ./ArduCopter-quad
Raspberry Pi 2 with BCM2709!
Raspberry Pi 2 with BCM2709!


Init APM:Copter V3.4-dev (be603da5)

Free RAM: 4096
FW Ver: 120
----------------------------------------


load_all took 265us
0 0 0 ▒ Q}▒▒3▒Calibrating barometer$▒▒  Q▒ ▒3▒barometer calibration completeJ▒3▒GROUND STARTFInit Gyro*▒        Q.PPuTTY*
INS
----------------------------------------
G_off: -0.00, -0.00, 0.01
A_off: 0.03, -0.11, 0.35
A_scale: 0.99, 0.99, 0.98



Ready to FLY  ublox ▒   Q_▒     Q▒!▒   Q▒               Q▒▒▒
Q▒C▒
        Q%=▒
Q▒M^CInterrupted

I think it is module related. Another compass works just fine …

It uses the same bus as baro, so probably the compass just messed up the whole i2c bus.