[50G] Question

[HrastProgrammer]

(05-03-2015 08:47 PM)DavidM Wrote:  Very nice, indeed. It's not often that I've run into examples of coding SysRPL in Saturn assembly form. This is a technique that I've seen before, perhaps even in one of your comp.sys.hp48 posts. I've never thought to embed SysRPL structures within a Saturn code object, but I can certainly appreciate its usefulness.

The main purpose of such dual DOCOL/DOCODE structure is to hide individual SysRPL words so the calculator will show only "Code" on the stack, otherwise the display would be overflowed with those annoying Externals.

I don't know if I was the first to do it this way, but I am certainly using this since 199x and something.

Quote:Perhaps the most interesting thing is that it's obvious from your code that the "old way" of setting contrast still works! I'm not sure why the historical postings I found indicated otherwise, and I feel a bit silly now for reinforcing that myth. The problems they pointed out were fairly specific, too. Makes me wonder if they only existed for older firmware revisions or in certain situations that weren't specified.

Early firmwares had a lot of problems and bugs so maybe this didn't work back then. Even the emulation of some machine language instructions was buggy. I made some explorations after HP-49G+ came out:

http://www.hrastprogrammer.com/hp49gp.htm

Some of those quirks/bugs were fixed in later ROMs I believe ...