[Coco] Tandy Hard Disk Controller

[Ward Griffiths]

On 03/03/2006 01:46 pm, Neil Morrison wrote:

> ----- Original Message -----

> From: "Gene Heskett" <gene.heskett at verizon.net>

>

> > Did they actually ever *sell* one?  I looked at the one the local shack

> > had, but at $129.95 I couldn't bring myself to write the check, NDI

> > what ever became of it.  AIUI at the time, it also required another

> > interface controller card between its cable and the drive proper &

> > nobody had a clue as to what it might be required to do, or if it was

> > even available.  It had a maximum of 3 16 pin dips in it that even if

> > gold plated, couldn't convince me it was worth the asking price.

>

> IIRC, you needed a R/S 'Primary Drive', which contained the HD controller.

> This was the standard R/S setup. The VERY expensive 'Tandy Hard Disk

> Controller' was just a very simple interface with a few chips.

>

> I'd like to get a schematic for it - never found one.


Might not be too hard to figure out.  The cartridge for the Coco was basically 
some firmware (I assume) and a conversion from the Coco expansion bus to the 
Mod 3/4 expansion bus, just as the boards that went into the Mod 2/12/16/6000 
were.  Yes, the primary drive box contained the actual controller.  The cable 
from a Mod 3/4 bus was straight-through.
-- 
Ward Griffiths    wdg3rd at comcast.net

I think boys might benefit from owning a Barbie doll; every young man
should understand what an expensive proposition it is to cohabitate with
a narcissistic woman built like a stripper.  --  Tony Woodlief