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General info on 48/49/50 ROM entry points
12-30-2017, 11:51 AM
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General info on 48/49/50 ROM entry points
I do already have the list of entry points compiled by Joe Horn and yes, it is an invaluable compendium of information.

Being interested in getting up to speed with Saturn ASM programming I'm most interested in the entries that have the "ML" suffix and therefore "do" something instead of just being addresses of RPL objects.

Some I'm familiar with ("DBUG.TOUCHE", "ErrjmpC", "GETTEMP" etc.), some I can guess at their purpose. Others.... Is there any documentation anywhere that describes what the code at these entry points actually does and how to use it?

The Saturn processor was clearly designed with manipulation of real numbers encoded in 16 nibbles in mind. The field structure of its internal registers gives that away in no uncertain terms. Surely there must be a routine somewhere that, for example, takes a real number thusly encoded in A.W or C.W, Allocates 21 nibbles of memory with the required availability checks, fills the structure with the prologue and the data from the register and sends a pointer to the structure to the RPL stack, right? Or do we need to reinvent the wheel each time because HP didn't feel that something like that would be useful?

Both UserRPL and SysRPL operate on the stack. The big advantage of ASM over them is that you can avoid using the stack altogether except to pass parameters to your ASM routine and to return results, and therefore save time. Surely there must be an entry point somewhere for each of the basic mathematical operations that operates on data in the registers, right?

As I understand it, a lot of documentation for HP machines and the Saturn processor is in French rather than English. That doesn't bother me, I'm bilingual anyway (j'ai passé presque la moitié de ma vie en France) I'd just like to sink my teeth into something that does a bit more than scratch the surface of what's in these machines.
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General info on 48/49/50 ROM entry points - grsbanks - 12-30-2017 11:51 AM



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