[Coco] Eproms

[Mathew Boytim]

Hi John,
 
Thanks for the reply but I think your numbering is off - a 27C64 would be 64 kbit in an 8kx8 configuration.  27C32 would be 32 kbit in 4kx8.
 
The transition from 24 pins to 28 pins usually occurs between 2732 and 2764 (4k and 8k).  The Model 1 w/ Level 2 Basic has 12k bytes of ROM.  At least the early one that I had had two ROM's - one 8k, one 4k, both were in 24 pin packages - and both on a satellite board that was connected to the mainboard by a ribbon cable an a few wires.  I think there was like a 2564 that was kinda rare but it was an 8k in a 24 pin package.  I think it was more convenient to replace the 8k ROM with a 2564 if you could find one.  I think eventually I replaced both ROM's and the satellite board with a single 16k EPROM and a few skywires.
 
I didn't know if there was a particular EPROM that worked out best in the Coco.  I'm more of a model 1/3 enthusiast but a friend clued me into the Coco mailing list and I've been monitoring some of the discussions.
 
Thanks again,
 
Matt

--- On Fri, 2/15/13, John Donaldson <johnadonaldson at sbcglobal.net> wrote:


From: John Donaldson <johnadonaldson at sbcglobal.net>
Subject: Re: [Coco] Eproms
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Date: Friday, February 15, 2013, 11:15 AM


If you talking 8K EPROMS then  something along the line of a 27C010 which is a 
8KX8 (64K) EPROM. These are the same size as the Basic ROMS.
IIRC   a 27C512 EPROM is a 4KX8 (32K) EPROM which may be the smallest you want 
to go with.

JohnD.




________________________________
From: Mathew Boytim <maboytim at yahoo.com>
To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
Sent: Fri, February 15, 2013 10:19:17 AM
Subject: Re: [Coco] Eproms

Which EPROMs are desirable for the coco?  I used to have stacks of EPROMs but 
when younger my daughter would make stuff with them and the antistatic foam and 
they got bent and damaged but I didn't care - and eventually pitched them.  I 
still have a small assortment though.

Matt

--- On Fri, 2/15/13, John Donaldson <johnadonaldson at sbcglobal.net> wrote:


From: John Donaldson <johnadonaldson at sbcglobal.net>
Subject: Re: [Coco] Eproms
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Date: Friday, February 15, 2013, 8:02 AM


Sorry Luis, but I am all out of EPROMS.

JohnD




________________________________
From: Luis Fernández <luis46coco at hotmail.com>
To: COCO <coco at maltedmedia.com>
Sent: Thu, February 14, 2013 10:22:38 PM
Subject: Re: [Coco] Eproms

Hi John Donaldson

Still have eprom?
I would like to change my controller to 28 pin and still use your eprom
                          

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