8085 vs 8085A - test-drb@ccmp.vtda.org

6 Aug 2007

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Subject: 8085 vs 8085A
   From: "river" <river at zip.com.au>
   Date: Mon, 06 Aug 2007 20:48:21 +1000
     To: <cctalk at classiccmp.org>

Hi,

I was looking through my collection yesterday and was testing out an old
Intel SDK85 system. I noticed the main processor is stamped 8085, which
means this chip is either an 8085 or the "A" was not printed properly and
the chip is really an 8085A.

I have a few 8085 systems and a box of 8085 CPUs. I checked them all and
every one of them is an 8085A. I don't think I have ever seen an 8085,
they've all been 8085A types.

Other than the stamp on the chip, is there anyway I can tell the difference
between an 8085 and an 8085A? Furthermore, is the 8085 rare, and I should
put the chip away, or is it nothing special? 
8085 (non A) is not rare but I have no data in my library for intel 
to suggest any differnce between the non-A and the A part.

...
 Why did Intel bring out the 8085A? Were there issues
with the 8085? 
8085 was 1977 and the 8085A from what I have was soon before!  Date 
codes suggest late  1977 (week 52 1977) for one 8085A.   I suspect
the differnces are processing only and they are interchangeable.

I should note that I only have a few intel 8085s in ceramic and 
8085As in both ceramic and plastic. So there may be insignificant 
process differnces.  Also only the 8085A appears elsewhere (NEC, AMD)
so the upgrade may be a license issue.

Allison

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Seeyuzz
River