For my company, I have to add an additional sensor. For this Sensor I want to use uartC which should be the connector USART2 in my opinion.
When I use the default frameware I can receive from this port all the times nulls. When I compile my code I get also nulls.
I am now wrong with uartC is USART2, or do I have to change more code except the ones with uartC?
Presently the USART2 connector is used to provide camera gimbal control on the PX4: http://copter.ardupilot.com/wiki/camera-mount/#PX4_Camera_Gimbal_Servo_Connection It could be that there is a conflict between your code and the gimbal control code that is using the USART2 connector pins for gimbal control.
thanks for the information! I have not see this. Do you know if there is any free uart which is accessible?
For the future we need the gimbal control, so It looks like, I can not use this connection.
The PX4 IO board has an USART2IO: http://copter.ardupilot.com/wiki/common-px4io-overview/ You might see if you can use that USART. The USART connection is right next to the power module. I do not know enough about the PX4 USARTs to be of much help:-)