[Coco] 256k upgrade

[Mike Pepe]

I recall that it included the 74LS785 SAM for the 256 column refresh required for the DRAMs. I think they used "reads" of the SAM control bits to select which bank of memory was active. Other than that I can't recall how it was accomplished.

> -----Original Message-----
> From: coco-bounces at maltedmedia.com [mailto:coco-
> bounces at maltedmedia.com] On Behalf Of Bill
> Sent: Monday, February 01, 2010 7:08 PM
> To: 'CoCoList for Color Computer Enthusiasts'
> Subject: Re: [Coco] 256k upgrade
> 
> I found "128K The Easy Way" in Dec. 1984, on page 162, but I cannot
> find the
> 256K article you mentioned. But I do remember it too...
> 
> > -----Original Message-----
> > From: coco-bounces at maltedmedia.com [mailto:coco-
> > bounces at maltedmedia.com] On Behalf Of Mike Pepe
> > Sent: Monday, February 01, 2010 9:23 PM
> > To: CoCoList for Color Computer Enthusiasts
> > Subject: [Coco] 256k upgrade
> >
> > Does anyone have a scan of the Rainbow article(s) that featured the
> > 256k upgrade for the CoCo1/2?
> >
> > I think it was a multipart project spread over many months. I don't
> > have a very comprehensive Rainbow collection and I was looking to see
> > if I had it- but I don't.
> >
> > Thanks
> >
> > -Mike
> >
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