2708 Programming Algorithm?

From: Richard Erlacher <edick_at_idcomm.com>
Date: Mon May 6 16:29:50 2002

It's been a long time, but since I just recently handled the old 8748 doc that
has the reference I thought I saw, it'll be cleared up soon.

I just remember that all the 87xx parts, 8741, 8755, 8748/49, etc, were all
5-volt parts. further, I'm not at all sure that the 8080 had below-ground
signal levels, since they were intended to be attached to bipolar parts, e.g.
8212, etc, which would have been intolerant of that. What I've got in my lap
is the 8080A data, which may, actually be different, but IIRC, the 8080 needed
the negative bias supply so it could swing to ground and the +12 so it could
swing to a reasonable high level. My only contact with the 8080 was on boards
made by Intel, and, while I poked around with a 'scope and other gear from
time to time, I don't recall ever finding an address, data, or control signal
that wasn't TTL compatible.

Dick

----- Original Message -----
From: "Dwight K. Elvey" <dwightk.elvey_at_amd.com>
To: <classiccmp_at_classiccmp.org>
Sent: Monday, May 06, 2002 3:07 PM
Subject: Re: 2708 Programming Algorithm?


> >From: "Richard Erlacher" <edick_at_idcomm.com>
> >
> >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.
> >
> >'t seems like I'll never learn to keep house ...
> >
> >Dick
> >
>
> Hi
> I believe the half bad 2716 of Intel's were call either
> 2758 or 2508, not 8708. I'm almost sure that the 8708
> was the one that could handle the negative bus levels on
> the input, as I said earlier. You are correct that they
> sold the H and the L version for the level to put on
> the A10.
> Dwight
>
>
>
Received on Mon May 06 2002 - 16:29:50 BST