20 Sep
2012
20 Sep
'12
12:42 p.m.
-----Oorspronkelijk bericht-----
Van: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org]
Namens Tony Duell
Verzonden: donderdag 20 september 2012 21:00
Aan: cctalk at classiccmp.org
Onderwerp: Re: Wanted : Dunp of HP9820 Peripheral Control II module
spriisngly hard
Interesting, very interesting...
The address is on its way.
Making an EPROM module fo rthe HP9800s is one of htose things htat looks
quite easy on paper -- the only oddity is the enable signal -- but when you come ot do it. Particualrly in the HP9810/20,
where the ROM
moduel
backpalen is wired up on a horrble bundle of wires
which have signficatnt
inductance. Decoupling well is essential, even then it;s not as easy as it
looks...
Put it is worththe effort. I noww have DataComm 1 for the HP9830, so I cna
finally make use fo the 11284 interface I have. I have C1 nd PC2 for the
HP(810,
so I can get that machine talking to a serial port,
etc. Alas
PC1 for the HP9820 doesn't allow the sort of low-level access I'd like,
which is
why I'd like PC2...
-tony
The same kind of project has come up to my mind.
I was planning to build a ROM-board for the 9830 so you can put all the roms
to 1 board.
I didn't came to at the moment, too much work and too much to do..
But I'm very interested to your implementation of the home made ROM boards.
-Rik