[HP48/49] Command Line Parsing

[Han]

(02-16-2015 01:01 PM)Bruno Wrote:  Hi,

I'm trying to improve the parsing routines of HPDL using the GetNextToken entry,
and I don't understand how it work, especially on the content of the hxs mask that it expect to find on the stack.

I think each one of the 256 nibbles represent a set of parsing rules to apply to the corresponding ASCII character,
but If I'm right, what is the meaning of each bit ?

Thank you for your help.

GetNextToken is actually a special pointer whose code resides at #1E181h. You can use Jazz on the HP50G to trace the algorithm via SDB and DB to get an idea of what the hxs mask is supposed to be. I haven't looked into the ROM beyond this; my suspicion, however, is that it may not be a mask but is instead a small scratch buffer to be used by the GetNextToken routine. I could very well be wrong.