HP-29C Neutral Operations

[brouhaha]

(02-10-2024 11:27 PM)teenix Wrote:  I don't think the ACT plays a part in this problem other than decoding the ROM instructions, so it seems the code [1 -> s9] is definitely there. I guess this may be a 29/19C error that could have been fixed in later ROMs, not sure.

I see that there are 1 -> s9 instructions in both ROM 0 (in the 29C ROM/Anode driver), and in ROM/RAM 3 (1818-0379, shared between the 19C and 29C). As far as I'm aware, ROMRAM 3 did not change in later revs, but the ROM0/anode driver did. I don't know whether the dump I have is from the original ROM/anode driver (p/n 1818-0378), or from the later one (1818-0431).