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Re: GAL's and PALASM



I had considered using GALs on that board. Could probably use 3, however since Andrew and I are at our 5th version of that board I would like to lay it to rest with regular 74LSxxx chips and move on.  A 40MHz CLK2 is not bad.
 
I look upon it at the last "simple" 74XX board in our Intel series.  The next board, a 80486 will actully have to use GAL's because of the way the CPU handles the data lines. Will rool in the othe GAL like circuits on that board.
 
 John
 
 

On Wednesday, April 16, 2014 9:12:25 PM UTC-10, David Fry wrote:
Hi John,
 
I'm not sure if it's too late in the day for this suggestion, but could the S100 80386 CPU clock circuit ( U15, U14 ) be implemented into one of these GAL chips
in order to reach the maximum CPU speed of the 80386.
The 16V8 datasheet shows these GALs to be way faster than standard logic chips (250Mhz 3.5ns prop delay) 
 
regards
 
David Fry

On Wednesday, April 9, 2014 6:45:21 AM UTC+1, monahanz wrote:
Guy's just wanted to mention I have "see religion" in terms of using GAL's to simplify our future more complex S100 boards.
 
As we move to CPU's like the 80486 and higher it is clear the 74LSxxx chips alone will not fit on a single S100 board to carry out the functions of these CPU's. I have also concluded that I will need them for out ISA to S100 bus converter board and XVGA type video boards.  These are all projects in the works and will probably not see the light of day for some months.

To expose GAL's to those that may not be fully aware of them, I have written up a short introduction here:-


Enjoy
John