HP-35 and HP-45 ROMs

[brouhaha]

(04-27-2023 09:28 AM)Z80Sarah Wrote:  The 45 ROM has the 'patent version' which gives a negative value for the STO- and a reciprocal value for STO÷ (compared to the documentation for my HP-45): this is brouhaha's 45 ROM. I recall discussing this briefly with brouhaha when I was debugging my old simulator. My note in the pdf accompanying that simulator reads (numbers are in decimal), "ROM 4 Byte 146: This is the only difference between the ROM codes used in the program and the listing in the patent. Sending program flow to ROM 4 Byte 142 (label: am11) causes internal registers A and C to be swapped. This swap results in incorrect results for some combined STO operations: STO ÷ gives the reciprocal of the required result and STO – gives the negative of the required result. Changing this line so that program flow goes instead to ROM 4 Byte 143 misses out this swap and corrects this error: the functionality of the simulator then matches what is described in the documentation available."

Thanks for keeping that information and sharing it now! I try to keep backups of all my data, but somehow the later 45 microcode info fell through the cracks.