[Coco] Pardon me for asking...

L. Curtis Boyle curtisboyle at sasktel.net
Tue Dec 14 13:43:00 EST 2021


If you want to test your 64K, see page 18 for Frank Hogg’s article (with a small BASIC program to type in) that will go into 64K mode with BASIC copied from ROM to the upper 32K of RAM, and also shows how to test to make sure it worked:

https://colorcomputerarchive.com/repo/Documents/Magazines/Color%20Computer%20News/Color%20Computer%20News%20%2319%20-%20April%201983.pdf


> On Dec 14, 2021, at 12:21 PM, Charles Hudson <charles484 at twc.com> wrote:
> 
> Well, the ROMs are another story, one where the tail wags the dog:  I have some other TRS hardware and a few years ago bought a Tandy Color Disk Drive thinking I could adapt it for use with a Model III.  Later I acquired a 26-3022 controller to drive it. Then I read that the controller needed 12VDC and that the CoCo 1 provided it, so I bought the CoCo.  It got damaged in shipping so I broke the seal and took it apart to repair the case.  While it was open I inventoried and found I had Color BASIC 1.1, no ECBASIC, and a 16k E board.  And video so shaky it makes you itchy just to look at it.  And the drive didn't respond.
> 
> I found I needed CB1.2 and ECB ROMs to talk to the drive.  No problem: I had EPROMS and EPROM burners, but then I found that the recommended EPROM, an MCM68766, required 25 VDC to program; a voltage my USB burners could not furnish.  I looked at adapter boards but decided against them because they interfered with the other components and prevented re-installation of the RF shield. I found a Needham's programmer on eBay but am still collecting the pieces for that, so I sent two blank ROMs to Cloud-9 for programming.
> 
> I still don't know if the damned TCDD is operational, but at least I have a CoCo to show for it, replete with 64K RAM and an Hitachi CPU.  Keyboard is funky and the video is awful but we'll get to that, I suppose..
> 
> -CH-
> 



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