At my wit's end with non-booting Tritium H5

[librecomputer]

Libre Computer Board Debug Serial UART Connection and Setup Guide

UART serial cables provide a means to get messages and errors from the board without having a graphical interface. It is critical for the debugging of errors that occur in early boot stages and in headless systems where graphics may not be available. A graphical stack or ssh connections might crash on an error so without this means of getting messages from the hardware, figuring out what went wrong becomes a difficult trial and error problem. Thankfully, UART serial cables are widely available …