switching eprom

[DC Smith]

Anybody got any idea who the first person was to do this?? ...
I heard of it and thought it'd be neat so I sat down and figured it
out.. Anyhoo..

 I've done this many times. I used 10K resistors to pull the extra
address lines high and a binary pushwheel or thumbwheel switch to switch
the different addresses (pull the line low). A dip switch setup will do
the same thing. Just think in binary terms. :^)

 I load the buffer in my chip program with as many programs the prom I
am using will hold using the (27256 = 8 cals to emulate a 2732, 27128 =
(4) 4K programs) program (and set it to not clear the buffer before file
load). (RomMax on a Pentium) I just offset the programs the file size +1
bit, when I load em. (I've got a PB-10 at work and find the RomMax more
to my liking)
 On a software/programmability issue..
 I don't think you can program the blocks individually using a .. say
27256 algorithm to emulate a 2732 (8 programs), since *my* programmer
will write from FF's to 00's on any unused areas.. and it won't pass a
blank check.. Maybe I can change this in the software setup, but I don't
remember being able to do it. I can at least bypass the "blank check
before programming" in the software.

 BTW, Hot Rod Power Tour is sposed to be at Gateway International
Raceway (St. Louis) this thursday. I _hope_ to get my heads back on,
motor back in, and be there, boosted and ready. This SFI'd ride ought to
really honk after this little tune up. :^)
 Machine shop's still got the heads.. gonna be close.. Hope to pick em
up in the morning after work..

 I feel a cold comin on.. <grin>
 
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Dan Smith      84 Regal   12.13 at 112     GSCA# 1459
St.Charles, Missouri 
mailto:dcsmith at bytes.net               
http://www.tetranet.net/users/morepoweral
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