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Re: Difference between 6502 & 65C02



In article <4je9a2$pc6@nnrp1.news.primenet.com>, johnlb@primenet.com (John Bowling) writes:
|> In article <4j862u$5k8@voyager.iii.org.tw>,
|> james keim <jkeim@unlinfo.unl.edu> wrote:
|> >John Bowling (johnlb@primenet.com) wrote:
|> >
|> >: I don't have any reference books on these anymore, but from what I recall 
|> >: there were a half dozen processors between 6501 and 6510, and the primary 
|> >: differences were the number of pins and how much memory they addressed.  
|> >: A few may have contained internal RAM/ROM.  It doesn't seem like a 6503 
|> >: would be software compatable with the IIe (designed years before the 
|> >: 65C02, as were all 65xx processors [without the C]) so it was probably a 40 
|> >: pin 6502 with internal RAM/ROM.  Possibly used because Apple found a 
|> >: bunch of them surplus and wanted to save some money. 
|> >
|> >: It can't be 65C02 compatable unless it was designated a 65C03, and I 
|> >: don't recall ever hearing about such a chip.

It is 65C02 compatible.  My CPU is labeled 6503 and runs every *enhanced* //e
program, and all of the older programs not making older ROM specific calls.

|> >
|> >: John
|> >
|> >
|> >John-- 
|> >
|> >There was some discussion of this some time ago on Genie.  I don't
|> >remember all the details but I think the kernel of the discussion was
|> >that one company started calling their 65c02 a 6503--probably just to 
|> >make things a little confusing.  As I remember, they are basically the
|> >same chip.
|> >
|> >Harold Hislop would know for sure if he is anywhere around.  I'm sure
|> >he was one of the principle parties discussing this chip.
|> >
|> >--James Keim
|> 
|> My previous post was referring to standard part numbers by the chip 
|> manufacturers.  OEM part numbers can be anything, and from what has been 
|> said in other posts Apple decided to call the 65C02 a 6503 as an 
|> internal number.
|> 

So, the 6503 I have in my //e is just an OEM 65C02A?  I have always wondered
about that, and until now, I had forgotten about it.

Michael Kelsey
mkelsey@eecs.wsu.edu
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"Your Apple II is only as limited as you make it!"
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