6 May
2002
6 May
'02
9:46 a.m.
I think that's been pretty well established, Pete.
I'll look for the reference only to clear up my own confusion. I've only
owned ONE 8708 and doubt I ever had a 2758 on hand. The 5-volt 2716 was so
easy to program I adopted it immediately and never looked back. My first 2716
programmer was on a 6502 with a 50 ms one-shot on the RDY line, triggered by
the SYNC signal, which locked the processor and the data latched on the
programmer, until the requisite time had passed. It was dirt-simple. Also, a
74133 would decode the 2716 into the top 2K without further ado. It was
delightful!
Dick
----- Original Message -----
From: "Pete Turnbull" <pete(a)dunnington.u-net.com>
To: <classiccmp(a)classiccmp.org>
Sent: Monday, May 06, 2002 3:30 PM
Subject: Re: 2708 Programming Algorithm?
On May 6, 14:20, Richard Erlacher wrote:
Now I'm really confused, Joe. Thanks for
stirring the coals, though.
I can't find any Intel memory data before '82, and by that time they were
on
5-volt-only EPROMs all the way. The brocheure
I'm thinking of, with
respect
to that 8748 evaluation board, has the
"it's a 5-volt world" slogan that
Intel
liked to use in promoting the 2716 back then, but
I'll find the '78 8748
book
eventually, since I just looked at it yesterday.
> >I do believe you've misread part of
the spec's, Joe. The 8708, IIRC,
is a
> >5-volt-only version of the 2708,
otherwise masqueraded as the 2758.
I hate to disappoint you, Dick, but my Intel 1979 Data Book lists the 2708
and 8708 on the same page, with the note "All 8708 specifications are
identical to the 2708 specifications", and then proceeds to describes all
he characteristics of a standard 3-rail EPROM. The 1976 book i referred to
earlier does list them in separate sections, but I don't see any
significant difference in characteristics, not even in input voltage range.
I think you're confusing it with the 2758, which the same catalog shows
right after the 2716, identical in all respects except that the 2758 has
A(R) on pin 19 instead of A10. A(R) has to be low for all device access,
even "standby" mode, except in the case of -S1865, when it has to be high.
It would appear that the 2758 is in fact a one-half-working 2716.
--
Pete Peter Turnbull
Network Manager
University of York