[Coco] 80 pin ultra wide SCSI drives for the Coco

[Gene Heskett]

On Friday 13 June 2014 16:03:48 Kandur did opine
And Gene did reply:
> Most old Coco HD controllers were made for 50 pin SCSI-1 drives.
> These days they are low on capacity, high on noise, rare
> and priced ridiculously high.

Humm.  I have a pair of 1Gb seagate Hawks, scsi-ii interface, on my TC^3 
controller, works great.  Those date back to the 90's and my amiga days.

> Enter the 80 pin ultra wide SCSI drives,
> they are high on capacity, low on noise and priced reasonably.
> Add a cheap 80+64+50+power adapter,  a 64 pin cable with terminator,
> use your 50 pin cable to connect it to the old Coco controller.
> It's in the testing phase here, now.
> http://qdv.pw/eng/_photos/Computers/Coco/hd-setup/
> 
> Kandur

That 73Gb is I believe well beyond what the coco/nitros9 can handle.  
OTOH, with 4Gb available as is, thats enough to archive just about 
everything ever compiled to run on the coco's.  That limit is of course 
set by the size of the FAT, which is limited to 64Kb.  But that, if a FAT 
bit is 64kb (256 sectors per cluster) then thats 34,359,738,368 bytes 
available per each "partition".  Room enough for 2 such partitions on a 
73Gb drive.  But while I haven't checked, I suspect the 24 bit address on 
the scsi-ii buss itself would be a smaller limit because of overflows, and 
the actual limit then would still be 34,359,738,368 bytes per drive.

I also have cabbaged some scsi-iii drives, 80 pinners, 300-500Gb 
capacities but haven't tried to cobble up the interfaces, they out of old 
apple video servers that have since self destructed when a fan failed.

When the first one fried after about 6 months, Apples attitude was too 
bad, so sad, but we have more at $7995 each.  At that point Jim started 
building our own, using linux, for about 2 grand each.  They are still 
working yet today.

That adapter & terminator stuff is out of style & generally out of the 
supply chains since scsi was largely beheaded by sata.

If someone still has that stuff on the shelf, please post the URL, I would 
invest myself if the medics leave me enough money.  I had a PE that almost 
punched my ticket 2 weeks ago last Wed. evening, but the clot buster shot 
($10G's) worked and I feel better than I have in months right now.  Free 
bleeder though, taking warfarin till whenever.  So I'll be around to 
heckle & be heckled for a while yet.  I'll hit the 80th in October. CHF 
signs, like vary fat feet, are fading away by the day, as is the weight 
they represented.

I am glad to still be here, and I'll make the statement that a Pulmonary 
Embolism (blood clot in the lungs) is a hell of a way to die, not at all 
pleasant.

Cheers, Gene Heskett
-- 
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US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS