Is it possible to add a third Telemetry port for Pixhawk4?

I am already using both Telemetry ports and I am planning to add a depth camera that needs to be connected to a Telemetry port.

A Telemetry Port is a UART and a simple Google search will show you how many there are:

Does it mean I can connect a radio telemetry module to for instance the UART & I2C B port, and everything will work as it should without confusing the Pixhawk/software?

UART’s a UART unless you need the RTS/CTS pins which you typically don’t for telemetry radios. Obviously you have to configure the port parameters for what you are using it for,

Nevermind. I was being stupid

That makes no sense. Mavlink is a protocol.

Yeah I know. I misunderstood. There’s just so much to learn about Pixhawk, I am glad I have this community. I am going to check and see if telemetry works on another UART port. But anyways. Now I am really curious, what if you eventually run out of ports? Is there a way to add more ports?

No, not really. Depending on what you are doing you can send the same data from a Tx port to more than one Rx in.

I have looked up UART. If I understand correctly, all UART ports has GND,Tx and Rx which is all that I need to connect Telemetry, Arduino, Companion computer etc. Did I understand this correctly?

Can I use the VCC from UART port to power up Arduino? What are Serial5 and Serial6 marked?