Cool! Yeah, it's pretty intense. I wonder how many people used it, and what the results were.
Do you want me to test anything with the HLCD0569? I've still got it hooked up to a PIC, so I could test any ideas you have. I think it's pretty much identical to the 0515, but they got rid of one of the columns to have room for the V DRIVE pin. I'm guessing DATA OUT is on pin 34- I'll try a read and see if it is. And I assume you can raise /CS at any time to stop shifting in bits early, and the remaining segments will keep their current state.
I saw you found a bad bit in Electronic Detective! I got out a couple of TMS0980s a few weeks ago to see if I could figure out how to electronically dump them, but they don't have osc inputs, so I don't know how to sync the K inputs to set the page and PC to dump.