[NBLUG/talk] Bare metal question

Andru Luvisi luvisi at andru.sonoma.edu
Sun May 25 12:32:00 PDT 2003


With respect to the 6502:

On Sun, 25 May 2003, Daniel Smith wrote:
[snip]
> You are correct.  Brings the total register count up to 3!
[snip]

However, there were several instructions that could do indirect addressing
via an address stored in the "zero page", which is to say the first 256
bytes of RAM.  This effectively gave you 128 16 bit registers, but you
took a speed hit when you used them.  My understanding is that C compilers
for the 6502 would put the C stack pointer in the zero page.

Andru
-- 
Andru Luvisi, Programmer/Analyst

Quote Of The Moment:
  C. A. R. Hoare once said that ``One thing [the language designer] should
  not do is to include untried ideas of his own.''  Ratfor follows this
  precept very closely -- everything in it has been stolen from someone
  else.
  		-- Brian W. Kernighan, "RATFOR: A Preprocessor for a 
  		                        Rational Fortran"




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