tle33710@uxa.cso.uiuc.edu (11/21/89)
According to the ATARI 130XE Owner's Manual, the Processor in the
machine is the 6502C Microprocessor, clock speed 1.79 MHz." Is this the
same as the 65C02, with more instructions than the 6502, as stated in the
MAC-65 owner's manual?
_______________________________________________________________________________ Tim Elliott | ``Genghis''
University of Illinois at Urpaign/Chambana | ``Enoch'' (Name of the Week)
tle33710@uxa.cso.uiuc.edu | ``Still mourning ANALOG''
-------------------------------------------------------------------------------
"I would never drink from headgear..." Dieter on Sprockets
Saturday Night Live 11/18/89
-------------------------------------------------------------------------------ehs@jumbo.dec.com (Ed Satterthwaite) (11/22/89)
In article <115200051@uxa.cso.uiuc.edu>, tle33710@uxa.cso.uiuc.edu writes: > According to the ATARI 130XE Owner's Manual, the Processor in the > machine is the 6502C Microprocessor, clock speed 1.79 MHz." Is this the > same as the 65C02, with more instructions than the 6502, as stated in the > MAC-65 owner's manual? No. The 6502C is a 6502 that is slightly customized electrically to Atari's specs. I think the ones I've seen were manufactured by Rockwell. The customization integrated a little glue logic that was found on the original 400 and 800. It's been a while, but I think the clock generation was changed and tristate buffers for the address lines were integrated. The 6502C was supposedly used in late 800 production (with a simplified CPU board) and in subsequent Atari 8-bitters. The 6502C is instruction-set identical with the 6502 but *not* pin-compatible. The 65C02 is pin-compatible with the 6502 (hence not with the 6502C) but has a number of useful extensions to the instruction set. I think the 6502C is NMOS; the 65C02 is CMOS. To add further to the confusion, (1) The 6502A and 6502B *are* just 6502s that are guaranteed to run at higher clock speeds. The original 800 used a 6502B, also clocked at 1.79MHz. (2) There are at least two different versions of the 65C02, one identified with NCR (or Western Design Center) and one identified with Rockwell; the extensions are somewhat different. Hope this helps. I have more info in my files at home if anyone really cares. Ed Satterthwaite ehs@src.DEC.COM / {...}!decwrl!ehs
Ordania-DM@cup.portal.com (Charles K Hughes) (11/23/89)
Tim writes: ----------------- > > According to the ATARI 130XE Owner's Manual, the Processor in the >machine is the 6502C Microprocessor, clock speed 1.79 MHz." Is this the >same as the 65C02, with more instructions than the 6502, as stated in the >MAC-65 owner's manual? > >_______________________________________________________________________________ Tim Elliott | ``Genghis'' >University of Illinois at Urpaign/Chambana | ``Enoch'' (Name of the Week) >tle33710@uxa.cso.uiuc.edu | ``Still mourning ANALOG'' >------------------------------------------------------------------------------- ----------------- No, the 6502C is a chip with slightly different pin functions. Atari just wasn't smart enough to realize that the 65c02 (or even better, the 65802) would be a vast improvement. Charles Hughes @cup.portal.com
chasm@attctc.Dallas.TX.US (Charles Marslett) (11/23/89)
In article <115200051@uxa.cso.uiuc.edu>, tle33710@uxa.cso.uiuc.edu writes: > > According to the ATARI 130XE Owner's Manual, the Processor in the > machine is the 6502C Microprocessor, clock speed 1.79 MHz." Is this the > same as the 65C02, with more instructions than the 6502, as stated in the > MAC-65 owner's manual? Nope, the 6502C has exactly the same instruction set (with it own funny idiosyncrasies) as the original 6502. It does have some (one?) extra pins defined to easily support the Antic chip -- I believe this is to synchronize passing off control of the address bus between the two chips. On the old 800 (which used a real 6502), the function was handled by some discrete gates and buffers -- so you could swap out the 6502 with a 65C02. No work with the 130XE (fie!) Charles Marslett chasm@attctc.dallas.tx.us