[Coco] 128K CoCo2

Kip Koon computerdoc at sc.rr.com
Mon Apr 20 23:39:42 EDT 2015


Hi Joe,
I have a Coco 1 with a Daughter Board plugged into the SAM chip's socket and the SAM chip is plugged into the Daughter Board.  The Ram is two sets of 4164 chips piggy backed.  I have also upgraded the 6809 to an HD63C09EP chip.  I would really like to be able to utilize the extra ram for something.  A Ram disk would be fine with me or for a printer buffer.  Any other uses would also be interesting.  This is my default Coco 1 setup I use to test new versions of NitrOS-9 L1 as well as new 16K DOS roms.  I wonder when we will see a 6309 version of NitrOS-9 L1?

Kip Koon
computerdoc at sc.rr.com
http://www.cocopedia.com/wiki/index.php/Kip_Koon



> -----Original Message-----
> From: Coco [mailto:coco-bounces at maltedmedia.com] On Behalf Of Joe Grubbs
> Sent: Sunday, April 19, 2015 5:13 PM
> To: CoCoList for Color Computer Enthusiasts
> Subject: Re: [Coco] 128K CoCo2
> 
> Yeah I'd have to write my own code to take advantage of the extra 64K. Just curious if anyone here has actually performed the
> upgrade and if 128K is the practical limit before doing some massive surgery.
> 
> FWIW the article can be found on page 162 of:
> http://www.colorcomputerarchive.com/coco/Documents/Magazines/Rainbow,%20The%20%28Clearscan%29/The%20Rainbow%20V
> ol.%2004%20No.%2005%20-%20December%201984.pdf
> 
> 
> 
> > From: os9dude at gmail.com
> > Date: Sun, 19 Apr 2015 14:41:18 -0400
> > To: coco at maltedmedia.com
> > Subject: Re: [Coco] 128K CoCo2
> >
> > On Sun Apr 19 2015, Joe Grubbs wrote:
> >
> >
> > > While searching for the reverse video mod in old issues of Rainbow,
> > > I stumbled upon an article detailing a simple way to take a CoCo2 to 128K.
> > >
> > > Has anyone ever done this? And is 128K the upper limit *without*
> > > doing massive surgery? This circuit was nice because it retained the
> > > SAM, added a few logic ICs, and used a piggyback set of 4164s
> > >
> >
> > There were several options to go 128k on the CoCo 1/2 and all of them
> > - if I recall correctly - were straightforward 32k bank switching
> > schemes, there was no way for plain old Basic to access the extended
> > RAM for programs but only as a RAM disk or printer spooler.  Maybe OS9
> > could make better use of the extra RAM.
> >
> > Don't recall ever seeing any software marketed for 128k.
> >
> > --
> > Coco mailing list
> > Coco at maltedmedia.com
> > https://pairlist5.pair.net/mailman/listinfo/coco
> 
> 
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco



More information about the Coco mailing list