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Re: A new S100 Bus 16MB Static RAM board.

Hi John

Please put me down for one of your new 16M SRAM boards.

Thank you
Leon Byles

On Thursday, October 30, 2014 9:19:56 AM UTC+11, monahanz wrote:

The 16MB Static RAM board sent out to many people earlier in the year seems to have worked fine – at least I have heard of no problems with it.

One thing that I did not like about that  16MB static RAM board was the need for the two mezzanine boards.  While the board works absolutely fine with any CPU I used with it (even our 80386 CPU board),  it is a tight fit in the S100 box. Also dare I say, it does not look pretty!   
Putting eight CY62167DV30 static RAM chips directly on an S100 board would be both difficult to fit and risky in terms of SMD soldering for many users.   With the advent of the newer AS6C3216 (4M X 8bit) static RAM chips, soldering 4 chips on a board becomes more practical.  

I rearranged the board so it can now be configured as a S100 bus 8MB board using the CY62167 chips or 16MB using the AS6C3216 chips.   This BTW, was the suggestion of Dave back earlier in the year.  While the 74LSxx chips have changed little,  the top half of the board had to be completely re-routed to accommodate the 4 SMD chips.  See here for a picture of the board:-

http://s100computers.com/My%20System%20Pages/16M%20RAM%20Board/16MG%20RAM%20Board.htm#A Second Prototype 16MB Static RAM Board

(bottom of the page).

 Anyway I checked out a prototype which seems to work  fine for 8MG with our 80386 board using the 80386 monitor RAM test and 2Mx8 chips.   Because it is a prototype, I have not yet tried the 4MX8 (16MB) configuration.

This is an expensive board using expensive chips (each 4MX8 costs $21), I do not expect many would be interested in getting a bare board like this,  but since I will be ordering 4 production boards for myself (gold fingers etc),  I will open the order up for a day or two for anybody else that would like one.