[Coco] Updating a CoCo 1's CB and ECB ROMs

[Phill Harvey-Smith]

On 26/12/2012 04:24, Juan Castro wrote:
> I've been mulling this for some time. Cloud9's DOS Adapter does in
> fact just this (meant for the disk controller) but there's no way
> two of them will fit side by side. (2.2 cm = 0.86 in)

When faced with a similar problem on the Dragon 32 which also has 24 pin
ROMS with the same pinout as the CoCo 1's I designed a little adapter, 
Eagle design files (and schematic pdf) are here :

http://penguin.stats.warwick.ac.uk/~stsxab/Dragon/RomAdapter/Dragon_CoCo_RomAdapter.zip

Should be easy enough to make up on stripboard or tripad tho.

The board is designed for a 27512, but there's no reason you couldn't 
use a 27128 or 27256, by setting the A14/A15 jumpers to the correct values.

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.