[Coco] 2MB Memory Upgrade For The Coco 3

[Stephen H. Fischer]

----- Original Message ----- 
From: "Gene Heskett" <gheskett at wdtv.com>
To: <coco at maltedmedia.com>
Sent: Sunday, August 05, 2012 10:52 AM
Subject: Re: [Coco] 2MB Memory Upgrade For The Coco 3


> On Sunday 05 August 2012 13:40:23 Stephen H. Fischer did opine:
>
>> Hi,
>>
>> Tony's "DISTO 2 Meg Upgrade" manual and the "inside the 2 Meg Upgrade"
>> book with schematics are on the web (Suggested that it is flawed
>> intentionally) .
>>
>> PM me for links if you are interested, we are not posting links even on
>> the list to try and keep the traffic down for the site.
>>
>> Getting parts may be hard if you wish to build your own.
>>
>> The inside book is useful for understanding how the 2 Meg Memory
>> upgrades work.
>>
>> SHF
>>
> My advice is that the book is far more useful in that it would let a savvy
> board(s) designer build his own with the devices he happens to have in the
> spares box.  I say that precisely because the 1 megabyte simms that kit
> used are, in the year 2012, made from 99.99% pure un-obtainium.  One must
> bear in mind that the refresh counters needed for more modern memory will
> often need expanded 2 to 8 bits beyond the measly 7 or 8 the coco 
> supplied,
> and that is at least as challenging a design project as the extra memory
> registers etc it takes to make a full 2 meg memory map, in 8kb pages.
> Memory with that width of refresh will also carry a longer time till
> refresh needed as it was forced to become less leaky in order to hold its
> data well till the next refresh cycle came around.
>
> Cheers, Gene
> -- 

Hi,

Gene, there is good news and bad news (Temporarily).

First, the good news, I found Tony Distefano's "Inside DISTO's 2-Meg Kit" 
files.

I have the high quality scans for "2-Meg DAT Board.psp", and "2-Meg Mem 
Board.psp". ~ 17 MB each.

I also see many copies of them in jpg format in an attempt to reduce the 
size. Poorly done, changing the gray background to white would be a better 
plan or something else.

My new scanner might do a better job. I still have the paper version, but 
where is unknown.

----------------------------------------------

Now the bad news.

I do not have the scans of the text, only an OCRed version.

I produced a HTML version and sent it to Paul Barton to check. He said it 
was OK, but I then found some typos later. I do not remember where I 
uploaded it to, I cannot find it on RTSI where I uploaded the C Compiler 
book scans to.

He was the person who produced an 8 Meg Memory upgrade for the CoCo3.

His webpage appears to be gone, perhaps someone can find it in the internet 
webpage archive.

Sock Master's web page has a link to his now gone web page. It was 
http://home.wwdb.org/irgroup/index.shtml

I found this (Using Search.com on CoCo3.com). I just had to copy a few more 
entries!!!

http://www.search.com/search?q=paul+barton+8+meg+coco3+memory+upgrade

----------------------------------

Nov 9, 99: Paul Barton reports that tests on the 8Mb Upgrade board are 
proceeding with good success, but he'd like to converse with others about 
how to get new 6309 test code onto his machine. He doesn't have EDTASM and 
finds converting assembly from a crosscompiler on MSDOS to be a pain too.

Nov 9, 99: The IDE project has put a new web page online

Oct 15, 99: First some bad news. it seems we've finally come to the 
realization that Stephen Disney has "disappeared into thin air" with some of 
the Coco community's hard earned money. He's left quite a mess behind him 
too. Publication of "The World of 68 Micros" will be permanently 
discontinued, and the MP3 "learn the 6809 project is of course down the 
tubes - as well as the bulk purchase of 6309s from South Africa. Anyone who 
has information about where this person is - and why he's ignored repeated 
attempts to get a hold of him PLEASE contact someone within the Coco 
Community. I have in the past listed Mr. Disney's offerings on this page and 
I apologize if you have sent him money because of this - at the time of the 
postings no one had any reason to doubt the sincerity of this person. In 
general, the Coco Community continues to be comprised of the finest people 
you will find anywhere - people with whom you can deal with confidence. And 
now on to the more positive things.

...

Oct 15, 99: Paul Barton reports his 8MB coco upgrade seems to be working! 
More testing is being done as I write. also ONLY ONE NoCan2 remains 
available ($60 usd).

----------------------------------

If someone wishes to try and clean up the ~ 17 MB original scans, send me a 
PM.

Gene, you have looked at this before I remember. Maybe you can remember 
where I uploaded it.

SHF