Ok, just for reference, here's the thread I initially started on this:
http://www.8052.com/forum/rea...&top=20390
After a bit, I decided to use this logic analysis software to try to track down the controls:
http://www.xs4all.nl/~jwasys/old/diy2.html
But, as I pointed out in this thread, the PC's parallel port interfered.:
http://www.8052.com/forum/rea...&top=20390
So, as suggested, I built a 'buffer board' to monitor and 'regurgitate' output to the port. The good news is, it works great! :) I can now monitor the board & send output to the parallel port with ease and without interfering with the operation of the lcd.
The bad news is, I still haven't figured out the operation. For reference, here are the two patterns I've managed to catch from the board. The first is what it does when it boots (this exact pattern was repeated with perfection every time it booted), and the second is a sample taken as text was being sent to the LCD (these files are digitrace files that can be opened with the small program listed above):
http://www.cei.net/~defiance/test1.dgt
http://www.cei.net/~defiance/test2.dgt
The outputs are as follows:
1 - 1.7
2 - 1.6
3 - 1.5
4 - 1.4
5 - 1.3
6 - nc
7 - nc
8 - 3.1
These are the only IO pins connected to the LCD. other than these are only power, gnd, and contrast.
NOW for the question:
Can anyone help shed any light on what's going on with these? I was originally thinking 1.4-1.7 were the data port, with 3.1 being something like EN and 1.3 being RS, with the LCD being operated something like a 4-bit 44780, but this looks horribly dissimilar. Any help? :/