Originally Posted by seanriddle
The patent Claus references, 4125901, shows 13-bit ROM, but it sure looks like 16-bit to me.
My bad- there are 13 groups of 16 rows, which should correspond to the 16 banks of 13 bits. There are 128 columns, so that gives 2048 13-bit words.
The ROM array is rotated 90 degrees from the TMS1x00; based on Fig 7c in the patent, I think the bottom rows are the msbs. That means rotating the die shot CCW should put it in the same orientation as the others. It looks like the byte decoder is sequential, but I haven't spent the time to figure out if it's top-to-bottom or bottom-to-top. I also don't know the order of the 16 pages- previously they were 0-7,F-8.
I tried to find the first word of the ROM dump in the patent ($1213), but didn't find it by observation. Of course, I'm not sure how similar the actual ROM is to the patent ROM dump.
Claus references HrastProgrammer, who has a TI-57 emulator for HP calculators which he created from reading the patents. I looked briefly for the ROM dump in his emulator, but didn't see it. The patent scan is clear and entering the dump again shouldn't be too difficult.