[Coco] Design files for 512k or more CoCo3 upgrade

Zippster zippster278 at gmail.com
Mon Dec 1 11:02:06 EST 2014


I went ahead and ordered boards and parts for John Turner’s 512k RAM upgrade.
I’ll report back as to wether we can consider it tested or not when I get
one together.

- Ed

> Begin forwarded message:
> 
> Ed, with the Coco 2 extra ram, there is a possibility of using the OS9 L2 method of bank switching, but the DAT for the switching would have to be set up the same as the Coco 3's MMU using the same addresses. Then the level 2 core routines could be used. The Coco 2 of course could not use the L2 graphics and that would have to be removed, but it could then could multi-task properly like the Coco 3. A method would have to be devised to switch "windows" as the Coco 3's windows are hardware based.
> There's a project and schematic of a 256k Coco 2 board in Hot Coco which was also produced commercially as well called the J&R Banker. There were ram disk drivers for OS9 L1 but I don't think it ever went much further.
>  
> Bill Pierce
> "Today is a good day... I woke up" - Ritchie Havens
>  
> 
> My Music from the Tandy/Radio Shack Color Computer 2 & 3
> https://sites.google.com/site/dabarnstudio/ <https://sites.google.com/site/dabarnstudio/>
> Co-Webmaster of The TRS-80 Color Computer Archive
> http://www.colorcomputerarchive.com/ <http://www.colorcomputerarchive.com/>
> Co-Contributor, Co-Editor for CocoPedia
> http://www.cocopedia.com/wiki/index.php/Main_Page <http://www.cocopedia.com/wiki/index.php/Main_Page>
> E-Mail: ooogalapasooo at aol.com <mailto:ooogalapasooo at aol.com>
>  
>  
> -----Original Message-----
> From: Zippster <zippster278 at gmail.com <mailto:zippster278 at gmail.com>>
> To: Bill Pierce <ooogalapasooo at aol.com <mailto:ooogalapasooo at aol.com>>
> Sent: Sun, Nov 30, 2014 1:07 am
> Subject: Re: Design files for 512k or more CoCo3 upgrade
> 
> Thanks Bill.  
> 
> I figured the Coco 2 upgrades would be RAM disks and maybe OS9.
> 
> - Ed
> 
> 
>> On Nov 29, 2014, at 11:59 PM, Bill Pierce < <>ooogalapasooo at aol.com <mailto:ooogalapasooo at aol.com>> wrote:
>> 
>> Ed,
>> Here's 512k SIMMS upgrade designed by John Turner. He states in the included text that this particular design hasn't been tested.
>> The files are for Eagle
>>  
>> FWIW, the Coco 2 upgrades beyond 64k (there were a few 128-256k maybe even 512k) were mostly used for Ramdisks and not much more.
>>  
>> Bill Pierce
>> "Today is a good day... I woke up" - Ritchie Havens
>>  
>> 
>> My Music from the Tandy/Radio Shack Color Computer 2 & 3
>>  <>https://sites.google.com/site/dabarnstudio/ <https://sites.google.com/site/dabarnstudio/>
>> Co-Webmaster of The TRS-80 Color Computer Archive
>>  <>http://www.colorcomputerarchive.com/ <http://www.colorcomputerarchive.com/>
>> Co-Contributor, Co-Editor for CocoPedia
>>  <>http://www.cocopedia.com/wiki/index.php/Main_Page <http://www.cocopedia.com/wiki/index.php/Main_Page>
>> E-Mail:  <>ooogalapasooo at aol.com <mailto:ooogalapasooo at aol.com>
>> <CC-512K-SIMM_256_Cycle_Refresh.zip>



More information about the Coco mailing list