9 Jun
2001
9 Jun
'01
10:12 a.m.
Yes, that's probably better and likely to remain useable for a long time, but I
was focused on the socket size. It's pretty easy to hack the board, but
building a daughterboard is somewhat more work than hacking the PCB. If wanting
a place to put a 27C512 (also 28-pins) is a problem, a mezzanine board on the
CPU socket might work, too. Then the EPROM board can be sold on eBay to a
"collector" who won't care what it is, and will pay enough to buy a new car
...
well, maybe a new card ...
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Saturday, June 09, 2001 2:52 PM
Subject: Re: IMSAI EPROMS
>
> It's probably not a bad idea to modify the EPROM board to accept the
> single-supply (Intel-style) 2716, or even 2732. It's not difficult, and,
once
What I would do is make a little daughterboard to take a 27(C)64. It's
not hard -- most of the pins are in the same place (address, data,
ground), so it's not hard to do even using stripboard. That way you keep
the EPROM board original (although I probably would replace the EPROM
sockets with turned pin types).
24 pin EPROMS, even the 2716 anmd 2732 are getting hard to find in the
UK, and are somewhat expensive. 2764s are available everywhere and are
cheap. And _every_ modern programmer can handle them (I've seen a few
programmers that can handle nothing smaller than the 2764).
It may seem a waste to replace a 1K*8 chip with an 8K*8 chip, but that's
progress,,,,
-tony