[Coco] Tandy Hard Disk Controller

[Bill Gunshannon]

> As I recall the Disto controllers were SASI/SCSI compatible. I had one
> with a 4-n-1 board. Most people used them with SCSI drives because later
> in the 80s small SCSI drives were the most available, and the older SASI
> drives were big clunkers. I seem to recall that you had to make a special
> cable to connect a SASI drive, but that was all. Not sure if there were
> different drivers (I don't think so) or any software parameters had to be
> changed -- other than the physical drive specs.
>
> I did some checking on the web -- SASI (Schugart Associates System
> Interface) later became SCSI. It was just a host interface, not a
> controller. It could be connected to several different controllers,
> usually housed in the drive enclosure. The Tandy CoCo controller could
> indeed have been a SASI interface. Any controller with a SASI interface
> could then have been used, not just Shugart. For a pic of one of the
> controllers, and a schematic of a SASI interface for a 6800/6809
> processor, go to http://www.swtpc.com/mholley/SASI/SASI_Hard_Drive.htm.
> SCSI controllers provide the interface and controller card in one unit,
> and have some enhanced features over the original SASI.


So then, are the Tandy Hard Disks SASI?  If I hook one up to one of
these Owl Interface PAKs will it work?  I have a 12M hard disk from
a Model 16.  It had (has?) Xenix on it but I have more than enough
Unix around that it is unlikely I would ever want to use it again.
If it will work on the COCO it will be of much more value to me.

bill

-- 
Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three wolves
bill at cs.scranton.edu     |  and a sheep voting on what's for dinner.
University of Scranton   |
Scranton, Pennsylvania   |         #include <std.disclaimer.h>