Yes indeed! The data sheets for the two parts will answer all the
questions. All one has to do is to stay awake. I wouldn't make such a
statement if I didn't know of instances where one has gone to sleep . . .
that's one who shall remain nameless . . .
Dick
-----Original Message-----
From: Tony Duell <ard_at_p850ug1.demon.co.uk>
To: Discussion re-collecting of classic computers
<classiccmp_at_u.washington.edu>
Date: Tuesday, October 05, 1999 3:18 PM
Subject: Re: Help wanted in dumping EPROMs
>>
>> This particular case might be just a bit more involved, since pin numbers
>> are more difficult for the unititiated to track between the 44-pin PLCC
and
>> the 40-pin DIP. However, it really doesn't require one be a rocket
>
>Hmm... A good data sheet will show the pin numbering and positions for
>the PLCC device.
>
>[..]
>
>> In fact, I'd recommend one attempt to do this via the EPP port.
>
>It's not much harder (if at all) to use the plain old standard parallel
port.
>
>The best way to think of an IBM printer port is that it's 12 TTL outputs
>and 5 TTL inputs that you can do what you like with. Use a 74157 (or
>similar) to multiplex the 8 EPROM data lines onto 4 of the inputs (control
>the mux with one of the outputs). Use 8-bit latches (3 would be enough) to
>latch 8 of the outputs (might as well make it the standard 'data' lines),
>using other outputs to select them. Use the 24 lines you get by doing that
>to address the EPROM, and read the data back in via the mux.
>
>-tony
>
Received on Tue Oct 05 1999 - 20:27:02 BST