2708 Programming Algorithm?

From: Richard Erlacher <edick_at_idcomm.com>
Date: Mon May 6 17:51:29 2002

Yes, but doesn't have major effect on the levels while you're within spec.

Dick

----- Original Message -----
From: "Ben Franchuk" <bfranchuk_at_jetnet.ab.ca>
To: <classiccmp_at_classiccmp.org>
Sent: Monday, May 06, 2002 4:28 PM
Subject: Re: 2708 Programming Algorithm?


> Richard Erlacher wrote:
> >
> > 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.
> But check the specs TTL compatible often is for 1 TTL S load for output
> lines
> max.
>
> --
> Ben Franchuk - Dawn * 12/24 bit cpu *
> www.jetnet.ab.ca/users/bfranchuk/index.html
>
>
Received on Mon May 06 2002 - 17:51:29 BST