Hi I have been following the raspberry pi to pixhawk connection using mavlink tutorial on ardupilot. I am using a raspberry pi 3. When I did the last step(ttys0) for connecting the mavlink I get stuck at waiting for heartbeat. I checked online and followed solutions but none have worked. So I have come to the conclusion that something is wrong in the wiring of the raspberry pi to the telemetry 2 port. Our wiring is correct but the wires are loosely connected as we do not know what to use for connecting the telemetry 2 jumper cable to the gpio pins. So my question is how and what do we use for connecting telemetry 2 port to raspberry pi gpio pins(like solder or is there something else) and how do I get past the waiting for heartbeat in the mavlink? Thanks!