Help--I'm about to package the board up and send it back

[mzs]

There are strange situations where you really do want to connect RX->RX and TX->TX e.g. with an Arduino. Because the labels on the ports are for 99.999% of normal use cases and not for how the hardware can really be used if you are actually thinking totally outside the box. And misleading labelling would add an extra layer of confusion to the confusion!

Here is the comment from the very strange source code which makes you wonder what is going on, what they are doing looks really stupid, but is the total opposite:

This code makes the Arduino not interfere with pins 0 and 1 which are connected to RX and TX on the FTDI chip. This allows the data coming from the FTDI USB 2 Serial chip to flow directly to another device. Since RX and TX are labeled from the Arduino’s point of view, don’t cross the wires, but plug the device’s RX wire into the RX pin 0 and the TX wire into the TX pin 0.

It is a neat trick. The summary would be: Arduino your task is to ignore everything, do absolutely nothing at all. I’m just going to borrow this built-in USB to UART that is normally used to program you, or watch output from your UART, to debug some other hardware.