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For those who have access to the ROM source or a disassembly of the ROM:

There are many blocks of RPL that do not seem to be enclosed in the typical :: ; (DOCOL and SEMI) environment, and are preceded by 4 nibbles. Does anyone know what these four nibbles stand for? Are they similar to library objects in the HP48 (2 nibbles for library number, 2 nibbles for library commands)? I am trying to picture the ROM as if it were the predecessor to the HP48 ROM, and this is my best guess. If you know more, I would love to hear about it.

Han

You could use the Emu42 debugger, set the trigger on access of one or more of those nibs preceeding certain RPL code, and see which routine it's called from;-)

I didn't do it so far, but my guess would go into an XROM direction, or maybe it's kinda property field for mathematical functions, like in the HP-48 .
Did you check the XROM table at the end of the ROM?

Quote:
You could use the Emu42 debugger, set the trigger on access of one or more of those nibs preceeding certain RPL code, and see which routine it's called from;-)

I didn't do it so far, but my guess would go into an XROM direction, or maybe it's kinda property field for mathematical functions, like in the HP-48 .
Did you check the XROM table at the end of the ROM?


I did not think to check, but I'll do that. Thank you for some really good ideas.