[sebhc] Z-100 upgrade modules (ZMAX memory upgrade and ZCLK clock) available

Robert Groh rgroh at swbell.net
Fri Apr 14 23:54:05 CDT 2006

As near as I can decode the instruction sheet -
  1.    No board cuts are needed
  2.   The six chips are: a replacement for U111 (1Kx4 ROM), 2  PAL's for U110 and U173, a 74ALS00 for U155 and a 74ALS10(04) for U166.
  I do remember the mod you are describing - in fact, I think I have a  kit for doing that around here somewhere. Never, obviously, installed  either one!
  Bob Groh

Dan Lanciani <ddl-cctech at danlan.com> wrote:  |The 2nd item is a ZMAX - Z100 motherboard memory maximizer kit by Rick 
|Pegg and produced and marketed by Graymatter Applications Software. 
|Works only with later module Z-100 motherboards, does include written 
|instructions for the modifications, the 6 specialized chips required and 
|27 (3 banks x 9 ICs per bank) 256K bit D-RAMS. Gives you a wacking 768K 
|bytes of memory!  You can also use the 32K RAM chips you remove to 
|upgrade the video system (instructions included).

Interesting; what are the 6 specialized chips?  We used to do this
with one multiplexor (74LS157?) and a bent pin on the memory decode
PAL.  Older machines needed a newer monitor ROM as well.

    Dan Lanciani
    ddl at danlan.*com
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