[Coco] DE1 expansion connectors "pitch" width

[sales at gimechip.com]

Originally, I was going to use four 256Kx16's in this design so that the 
FPGA could access each chip individually and only use what it needed. 
However, this turns out to be impracticle - it would require both expansion 
connectors - there aren't enough pins on one expansion connector to support 
four chips - i was going to connect all address and data lines together, as 
would be expected, but leave the CE,UB,LB,WE signals seperate for each 
chip - i was going to use 1 of 4 demultiplexers for each signal so that only 
2 fpga pins would be needed to select the CE (or UB,LB,WE signal) of each 
RAM, but it still consumes too many pins.  I will likely attach OE of each 
chip to ground which will force WE to act as R/W*. So, I am going to create 
an EAGLE part for the BGA 1Mx16 SRAM from Alliance. Then I'll get back to 
work on this. Still need the pitch info of the expansion connectors tho' - 
I'll Google that after I create the 1Mx16 library part. -John

----- Original Message ----- 
From: <sales at gimechip.com>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Sunday, June 13, 2010 2:18 PM
Subject: [Coco] DE1 expansion connectors "pitch" width


> What is the "pitch" of the DE1 expansion connectors? Is it 2.54mm or 
> 2.0mm, or something else? I've decided to lay out a quick design for 
> 2-megs static RAM and an additional PS/2 port to plug into one of the 
> expansion connectors. As I don't have a DE1 I'll have to rely on you folks 
> to examine the design and let me know if it's feasible. I am working on 
> the schematic right now, but I need the info on the pin spacing of the 
> expansion connectors. Thanks - John
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco


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