[Coco] Seeking ECB Rom in the US

[Frank Swygert]

Date: Fri, 25 Jan 2013 22:32:32 -0500
From: "Kip Koon"<computerdoc at sc.rr.com>

Bill,
You are correct.  Although I did not mention it to Sean, I was thinking
about getting the needed A14 address line off the motherboard for pin 27 of
the 27256 which is a 28 pin device and will fit into the 28 pin socket on
Sean's Coco 2B motherboard. On the 27128, pin 27 is the PGM/ "PGM Not"
signal which of course is not needed to use the eprom in the coco 2B.  If it
is not connected to anything you could just connect 27 to a pin with A14
directly.  However, if they did connect pin 27, then the trace will have to
be cut first before connecting pin 27 to A14 somewhere.  I'd have to see the
schematic for the Korean Coco 2B before I could say.  By any chance, A14
wouldn't already be connected to pin 27, would it?
Otherwise Sean, I'd need to burn an extra eprom for you.  If so, please let
me know what type of socket the cart has for the disk controller.
Kip
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Just bend pin 27 out on the EPROM so it doesn't go into the socket then solder a jumper wire to it to go to A14 somewhere. Not trace need be cut!

IIRC the disk controller EPROM is the same type as the ECB EPROM -- 8K.