HP-41 ROM / Nsim emulator


I downloaded the Nsim emulator (the only one, it seems, that will run on Unix/Linux) and compiled it. However, I don't have a ROM in the format that it wants. All the HP-41 ROM images I have are in raw binary or p41 format, and the simulator wants a text file with ROM addresses and ASCII hex values, one per line. I can't find any conversion software to do this (there's a format converter for Windows, but it doesn't seem to support the format I need among its half-dozen).

I can whip up a converter to do this without too much pain (though it'll either run on Mac or Linux -- I don't have a Windows box at home)... but if someone already uses Nsim and has the ROM file in the proper format, I'd be indebted to you for a copy.


The reason Eric doesn't include the ROMs with the simulator is because they are copyrighted and, though he has asked, HP has not given him permission to copy them.


That's cool, I understand. I have ROM images, but only needed a better understanding of how to translate them to the proper format and assign correct memory addresses to the ROM partitions. When my CDs arrive with the 41 doco, I should get even smarter about how to do this. :-)

I got a couple of pieces of EMail explaining this a bit better, so I'm working now on hacking something together which should allow legit owners of the ROMs to convert them to the Nsim format. If I get a chance to complete something usable (as opposed to a hack that only I can use :) I'll mention it here. Thanks, all.


I use Linux and nsim all the time myself. It's great.

I only have images for the 41C, PPC rom and extended functions modules, so if you do generalize it, I'd be interested. (I'd like to get some of the other modules in there.)



Hi Bill,

Could I possibly get the PPC rom and X-funcs/mem rom for NSIM from you?




That would be great!

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