8080 vs. 8080A - test-drb@ccmp.vtda.org

30 Sep 2001

On Sep 30, 22:42, ajp166 wrote:
...
  From: Pete Turnbull &lt;pete(a)dunnington.u-net.com&gt;

...
  >Ah, then you'll know what the difference(s)
was/were.  While looking up
 >8080A and 8080 (except all my 1976 and 1979 Intel Data Books say is that
 >they're functionally and electrically compatible) I discovered that NEC
 >made two versions, both called 8080A, but one with some enhancements.  I 
...
  Ah no, not a V20 thing.  The first version of the NEC
8080A was not fully
 compatable at the hardware level.  It was the interrupt/hold thing. 
Makes sense.  Timing on the Intel part was a bit tricky, I seem to recall.
 Or maybe it just seemed that way to a beginner, at the time :-)

But I just came across (while loooking for something completely different)
a reference to a BCD subtract on the NEC part (or one of them).  What was
that about?

-- 
Pete						Peter Turnbull
						Network Manager
						University of York