[sebhc] H89 roms

Robin England robin.england at dial.pipex.com
Thu Dec 15 11:39:49 CST 2005


That's great news about the MTR ROMs, Lee. I'm waiting anxiously for a copy
of the 444-142, but there's no pressure...   ;-)

BTW, does anyone already have binaries or logic diagrams for the PALs used
as memory and I/O map decoders (U516 / U517 / U550)? If not, perhaps we
should look at 'probing' these?

I would guess that it should be a relatively easy task to run through the
input addresses and monitor the output select lines to work out the logic
function. Then, if a PAL fails, it should be possible to replace it with a
programmed EPROM or use a newer PAL / CPLD (e.g. on a daughterboard if the
pinout is different).

----- Original Message ----- 
From: "Jack Rubin" <jack.rubin at ameritech.net>
To: <sebhc at sebhc.org>
Sent: Thursday, December 15, 2005 1:39 PM
Subject: RE: [sebhc] H89 roms


> Lee,
>
> Please send me copies or upload them to the SEBHC ftp site and I'll put
them
> in the archive.
> Thanks.
>
> Jack.
>
> > -----Original Message-----
> > From: sebhc-bounces at sebhc.org
> > [mailto:sebhc-bounces at sebhc.org] On Behalf Of Lee Hart
> > Sent: Wednesday, December 14, 2005 12:39 PM
> > To: sebhc at sebhc.org
> > Subject: Re: [sebhc] H89 roms
> >
> >
> > Mark Garlanger wrote:
> > > If someone on the list has a way of reading the chip, but
> > doesn't want
> > > to take it out of their system, I have a loose 444-142
> > which I could
> > > let them borrow.
> >
> > I have all of the H19 and H89 ROMs on disk already as .HEX
> > files. But it's an
> > H17 disk :-)  Give me a couple days to get a modem cable
> > between my H89 and
> > PC and I can send them to anyone who needs them.
> >
> > For that matter, I have an EPROM programmer and plenty of
> > blank EPROMs for
> > these old chips. It's a Valley Data Sciences EPROM
> > programmer, which runs on
> > the H89.
> > -- 
> > Lee A. Hart    814 8th Ave N    Sartell MN 56377
> > leeahart at earthlink.net
> > --
> > Delivered by the SEBHC Mailing List
> >
>
>
> --
> Delivered by the SEBHC Mailing List

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