noetic mavros rqt_runtime_monitor reports Failure to connect to FMU, Raspberry Pi 4b to PX4 (Pixhawk) on Ubuntu 20.04

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Common Sense lesson when working with serial ports. If you spent an extensive amount of time trying to figure out what's wrong and you wired them yourself make sure that the TX wire is going to the RX wire and not the TX wire. Lol. Sounds like such a dumb mistake and it is but I wasted a week trying to come up with a solution software and every other way until I just broke it down and I realized all of the pins were transmitting correctly the power was there and some guy on a forum asked a guy with same problem if tx was going to rx or tx, and I thought to myself dude would I possibly make that mistake and then I was just like oh my goodness I checked it and sure enough I miswired it. That's equivalent to the service call where you show up and you ask them is your PC plugged in? They argue with you they say of course it is don't check it and you check it anyways and their PC is unplugged 😂 it happens to us all I think (burst my bubble if I'm alone;) I restarted my computer and mavros worked immediately on serial0. it's been so long since I worked on serial ports I forgot the basic rules if it doesn't work it's the most basic thing it's probably not a software issue.