# MAVLINK Bridge ### Serial Connection Pixhawk TELEM2 is internally connected to the Jetson module. Let us first check the connection on the Jetson terminal. Consider having a MAV connection to companion computers in advance. Check [PX4 Docs](https://docs.px4.io/main/en/companion_computer/pixhawk_companion.html#serial-port-setup) for the details. For a sanity check, you could run[ mavlink shell](https://docs.px4.io/main/en/debug/mavlink_shell.html#mavlink-shell) on `/dev/ttyTHS0` ### Ethernet Connection Since there is no DHCP server active in this configuration, the IPs have to be set manually:\ Once the Ethernet cables are plugged in, the `eth0` network interface seems to switch from DOWN to UP. You can check the status using: ``` ip address show eth0 ``` You can also try to enable it manually: ``` sudo ip link set dev eth0 up ``` It then seems to automatically set a link-local address, for me it looks like this: ``` ip address show eth0 2: eth0: mtu 1500 qdisc mq state UP group default qlen 1000 link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff inet 169.254.21.183/16 brd 169.254.255.255 scope global noprefixroute eth0 valid_lft forever preferred_lft forever inet6 fe80::yyyy:yyyy:yyyy:yyyy/64 scope link valid_lft forever preferred_lft forever ``` This means the Jetson’s Ethernet IP is 169.254.21.183. #### IP setup on FC Now connect to the NuttX shell (using a console or the MAVLink shell) and check the status of the link: ``` ifconfig eth0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx at DOWN inet addr:0.0.0.0 DRaddr:192.168.0.254 Mask:255.255.255.0 ``` For me, it is DOWN at first. To set it to UP: ``` ifup eth0 ifup eth0...OK ``` Now check the config again: ``` ifconfig eth0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx at UP inet addr:0.0.0.0 DRaddr:192.168.0.254 Mask:255.255.255.0 ``` However, it doesn’t have an IP yet. I’m going to set one similar to the one of Jetson: ``` ifconfig eth0 169.254.21.184 ``` And check it: ``` ifconfig eth0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx at UP inet addr:169.254.21.184 DRaddr:169.254.21.1 Mask:255.255.255.0 ``` Now the devices should be able to ping each other. Note that this configuration is ephemeral and will be lost after a reboot, so we’ll need to find a way to configure it statically. #### Ping test First from the Jetson terminal: ``` ping 169.254.21.184 PING 169.254.21.184 (169.254.21.184) 56(84) bytes of data. 64 bytes from 169.254.21.184: icmp_seq=1 ttl=64 time=0.188 ms 64 bytes from 169.254.21.184: icmp_seq=2 ttl=64 time=0.131 ms 64 bytes from 169.254.21.184: icmp_seq=3 ttl=64 time=0.190 ms 64 bytes from 169.254.21.184: icmp_seq=4 ttl=64 time=0.112 ms ^C --- 169.254.21.184 ping statistics --- 4 packets transmitted, 4 received, 0% packet loss, time 3077ms rtt min/avg/max/mdev = 0.112/0.155/0.190/0.034 ms ``` And from the FC in Nuttx Shell: ``` ping 169.254.21.183 PING 169.254.21.183 56 bytes of data 56 bytes from 169.254.21.183: icmp_seq=0 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=1 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=2 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=3 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=4 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=5 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=6 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=7 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=8 time=0 ms 56 bytes from 169.254.21.183: icmp_seq=9 time=0 ms 10 packets transmitted, 10 received, 0% packet loss, time 10010 ms ``` #### MAVLink/MAVSDK test For this, we need to set the mavlink instance to send traffic to the Jetson’s IP: For an initial test we can do: ``` mavlink start -o 14540 -t 169.254.21.183 ``` This will send MAVLink traffic on UDP to port 14540 (the MAVSDK/MAVROS port) to that IP which means MAVSDK can just listen to any UDP arriving at that default port. To run a MAVSDK example, install mavsdk via pip, and try out an example from [MAVSDK-Python/examples](https://github.com/mavlink/MAVSDK-Python/tree/main/examples). For instance: ``` python3 -m pip install mavsdk wget https://raw.githubusercontent.com/mavlink/MAVSDK-Python/main/examples/tune.py chmod +x tune.py ./tune.py ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.holybro.com/autopilot/pixhawk-baseboards/pixhawk-jetson-baseboard/mavlink-bridge.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.