V6X has several serial port Serial Port Mapping
So far, I tried TELEM3, UART4, they all worked for mavlink or ros2 communication.
But TELEM2 not works.
By param show -a
x SER_TEL1_BAUD [853,1424] : 57600
SER_TEL2_BAUD [-1,1425] : 921600
SER_TEL3_BAUD [-1,1426] : 57600
the default SER_TEL2_BAUD is 921600. So start mavlink at default baud rate
mavlink start -d /dev/ttyS4
it not works.
Change baud rate to 57600, then start mavlink on
param set-default SER_TEL2_BAUD 57600
reboot
param set SER_TEL2_BAUD 57600
mavlink start -d /dev/ttyS4
still not works.
Just can not figure out what’s the different between TELEM2 and other UART like TELEM1 or TELEM3