I’m pretty happy I FINALLY got the arduino to hook up correctly with two different hd44780 displays. I used the arduino example found here. I had done this before, but I found out that the Liquid crystal library is kind of broken. It needs to have a few lines swapped out in order to load properly in arduino 11.
After that I dug out my crystalfontz cfah-634 serial LCD and tinkered with it for a bit. I’ll update this with pics and more details later on, but there needs to be two jumpers closed on the back of the 634. I think the two jumpers are for “inverted” and “0 to 5v” The display seems kind of twitchy right now. That might be because I have it at 9600 baud, and it might be because I have all of the wires coiled into bundles. That could probably set up some weird ghost signals on the serial line.
One thing that I am having trouble with is that it seems like the display won’t behave properly if the “serial.Print()” code is in a subroutine. That’s fine for now, but it certainly makes things tougher down the line.
All of the mess and wiring trouble I had hooking up the 8 bit display has really made me want to dig out the phanderson serial backpack I have and build it.