[Coco] CoCo 3 memory expansion questions

[RETRO Innovations]

On 2/2/2019 4:02 PM, Neil Cherry wrote:
> I've ordered the Boomerang board (with the buffer board) and I'm 
> trying to
> understand what I'm hooking up (for better documentation). Does anyone 
> have
> a Coco 3 schematic with the 2 memory connections? I'm trying to 
> understand
> what is connected to what. I think I can use the same board on my Sardis
> ST2900 (a partial clone of the CoCo.
>
The 2 connectors bring out your standard 16 bit DRAM complement of signals:

RAS

CAS

D0-D15

ADDRESS0-ADDRESS8 (multiplexed, as DRAM addresses are)

WE0 (write to data 0-7)

WE1 (write to write to data 8-15)

+5V

GND


I put a EAGLE library online with the connector pinout at:

https://github.com/go4retro/EAGLE_lbr/blob/master/coco.lbr


Jim

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