[Coco] Back to the COCO

[Bill Gunshannon]

On 1/1/17 5:03 PM, Bill Pierce via Coco wrote:
> Bill, sounds like dirty or misalligned heads as the drive seems to be looking for track 0. I would bet dirty since you tried multiple drives. Keep in mind, not only has your system been setting, but so have the disks. I had close to 200 disks and they had set for about 15 years. When I tried to read them, the drive head would immediately collect "residue" on it (black mylar dust, and sometimes mildew). I ended up cleaning the heads after every disk copy (90% alcohol & cotton swabs) and sometimes after just a couple of file copies, after which most of the disks were no longer readable. I was able to copy about 75% of my content but it was a one-time thing.  I had some disks that were flooded and under water after hurricane floyd (1999), some that were in a storage building with no heat/air, but dry, and some that were in my closet (basically, climate controlled). Oddly, the flooded disks almost all read after a little cleaning, most of the ones from storage would read. The ones in my closet gave me the most trouble and were the most unreliable.
>  Also, try reseatiung the GIME chip. This helps in a lot of cases for a lot of problems. Reseat any socketed chips, cleaning the pins and sockets as best you can.
>

Thanks for the suggestions, some further comments.  Disk drives work on
other vintage machines and PC's so I don't think it's the drives.  Teac
55-GFR is running out of any container so I can actually watch it work. 
Too many different disks, both type and vintage, remember I also tried
3.5" which I have used on the COCO in the past.  As for the GIME, exact
same symptoms on a COCO2 so while still possible it seems highly
unlikely.

And, as stated, exact same symptom trying to do hard disks using the
Glenside and SCSI controller.  Of course, I have an SDC and it works
fine.  I guess the next test is to try the SUPERIDE.  It booted from an
already existing disk.  I will need to see if I can create new ones in
NitrOS9 and HDB-DOS.

Open to any other suggestions.  I haven't tried yet, but maybe I need to
set up an emulator with a real FDC and try the drives on that.  If I
figure out what it is I will post something here as I am sure others
have or will run into the same kind of problem as our systems age.

>
>
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> Bill Pierce
> "Charlie stole the handle, and the train it won't stop going, no way to slow down!" - Ian Anderson - Jethro Tull

Not just Jethro Tull, Locomotive Breath!!

bill