I tried running the ROMs from the HP-32E, HP-33C, and HP-37E (Spice series calculators) on nonpareil today. I’ve suspected for a while that the processor architecture was very close to the Woodstock series (e.g., HP-25). But I didn’t really expect them to work. They actually came up and ran, with minor issues.
The keyboard and display mapping isn’t correct, and they use the octal 0520 opcode, the function of which is unclear. I think it may be the “circular shift left A” instruction, but I’m not certain.
I’ve just spent a few hours getting my romsucker working again, and capturing a trace in which I pressed all the keys in a known order. From the trace I then determined what the keycode values are, and am about to put them into the KML files.
The display will take a little more work. There are only ten digits, vs. twelve in Woodstock, but there is a partial eleventh digit at the left used only for the mantissa sign. Since the display scan only uses ten digits from the A and B registers, I’m guessing that the sign might come from the leftmost digit of B (which is otherwise used to indicate the decimal, comma, and special characters like”E”, “r”, and “o” to spell out “Error”).