Helping a friend with a Pixhawk clone (rtfhawk). Upgraded to 3.6, now airspeed sensor is stuck at 5mph and does not move. pin is set to 65, and the airspeed + external compass on GPS are connected to the i2c splitter.
At a loss here - not sure how I can test to see if the airspeed sensor is actually broken or what…
Also seeing odd behavior where FBWA/B dips slightly left with no stick input (yes re-calibrated IMU’s)
-replacing all i2c cables
-tried new i2c splitter
-Enabled/disabled airspeed sensor with power cycled in between
-cycled through all available settings for pin for the hell of it (left at 65 now as instructions state).
Any help would be greatly appreciated!
Same problem here:
If external compass is connected nothing no I2C component works.
As soon as the I2C compass is disconnected Airspeed sensor works again.
I tried moving back to 3.5.0. no luck…
Any helpp would be gratly apprecited!
Loaded AC 3.3. then AP 3.5 and everything works by default. so I loaded back the 3.6. Oh joy! still works.
Speculation: you need to have all I2C components hooked up when you load the FW.
Any DEV insight would be greatly appreciated!
If system is booted without All I2C Components being connected components fail to initiate. Unfortunately it will not initiate even after reconnect.
on the 3DR GPS there is a small 3V rechargable battery “MS621FE” I am not sure what the purpose of it is, but if the voltage drops under 2.85V (2.5V unpluged), that is when you get I2C bus issues, slow GPS lock, max 6-7 satellites to fly with.
I have 2 GPS units and soldered in new batteryies in both, with measured 3V. (MEASURE BEFORE SOLDER!!! i was able t pick 2 out of 20 in the shop).
The result: Everything works on both! I have 8 satelites by the time I turn arround and press the CONNECT on MP and 10-11 by the time of takeoff.
This doesn’t really explain why the issue is only present with Plane 3.6, and how that by reverting to 3.5 you got this working. I have the same issues. Are you suggesting that by replacing that battery, all your i2c connected sensors are now working properly on f/w version 3.6, including your airspeed sensor?
I agree, but it worked and nowadays I am happier than curious so due to the lack of time I just went on to the next point.