[Coco] STATUS - Re: Resurrecting a CoCo (26-3001) with a 26-3029 FDC.

[Arthur Flexser]

When you say you get IO errors "at the end" of the formatting routine, I suspect
you are actually getting them in the middle of the routine, when DSKINI has
finished writing the tracks (or trying to do so, at least) and first attempts to
read back from the disk to make sure everything went okay.  So, that raises the
question of whether your drives are able to read (or write) anything at all.  
Have you checked to see whether an already-formatted disk can be read?  Does the
drive light come on when a drive is accessed?  It sounds like you might have a
hardware problem with your disk controller, if both drives are equally affected.
(If the drive lights are on all the time, you may heave a sigh of relief, for
that would mean simply that you've plugged the drive cable in upside down.)

Art

On Fri, 12 Sep 2008, Ryan Pritchard wrote:

> Hi all,
> 
> Thanks to everyone who had responded the to my original post.  Here is  
> a status update, and from the status I am hoping for some further  
> assistance.
> 
> Thanks go out to Darren A for setting me up with a Extended Color  
> Basic 1.1 ROM.
> 
> My 26-3029 FDC is the 7 chip WD1773 based version thus I will not be  
> able to mod it to work at HD.  Oh Well!
> 
> I have been trying to format disks in either 3.5" or 5.25" (I can't  
> believe I had two boxes of KAO 5.25" DSDD never opened kicking  
> around).  Anyway I get IO errors at the end of the formatting routine  
> regardless of 3.5" or 5.25" drive / media.
> Here is a list of my 5.25" FDDs:
> Panasonic JU-475-4 A55
> Panasonic JU-455-5 AAG
> Teac FD-55GFR-570-U
> Teac FD-55GFR 149-U5
> Mitsumi F509V3
> 
> 3.5" FDDs
> Fujitsu M2537D15D
> Fujitsu M2537B11D
> Teac FD-235HF 3240-U5
> 
> For all the drives I have tried to ensure that the DC/RY jumpers are  
> set to Drive Ready and not Drive Change.  I have jumper settings for  
> some of them, but it seems to not help. The cable I am using has been  
> returned to straight through mode.
> 
> I am still looking for confirmed 64K ram upgrade instructions for the  
> 26-3001 REV E board.  Currently it has 16K installed, the jumpers all  
> mention the 32K setting.  The closest instructions I have found are  
> from an archive of Paul Demarni's Coco pages (http://www.geocities.com/theother_bob/coco_page.html 
> ).  It instructs about the 32K upgrade and makes reference to him  
> having instructions for the 64K upgrade.
> 
> The other resource I have read about is from the October 1983 issue of  
> Color Computer Magazine, I really hope someone has that issue, that I  
> can acquire a scan of the article or arrange to acquire the issue.
> 
> Regards,
> 
> Ryan Pritchard
> Fun Extends All Basic Life Expectancies
> 
> 
> 
> On 24-Aug-08, at 9:53 PM, Ryan Pritchard wrote:
> 
> > Hello out there,
> >
> > Newby to CoCoList and to running a CoCo, but not OS-9 which I am  
> > looking forward to running the NitrOS-9 flavour.
> >
> > Fourth attempt to post but this time it should work thanks to Dennis  
> > telling me some information about the mailing list server.
> >
> >
> > I have recently got the bug to play with a CoCo I had acquired years  
> > ago.  The good news for me, is the 26-3001 model I have is the  
> > Revision E mother board which has all the jumpers on it to go all  
> > the way up to 32K (and likely 64K since I know the 64K x 1 chips I  
> > have are all good as they are coming from an Apple 80 Column card.
> >
> > Currently the CoCo has 16K in it, and boots up to Color Basic 1.1.   
> > It has an empty ROM socket where if I have understood correctly I  
> > could install and Extended Basic ROM if I had one.
> >
> > I am having a problem getting the Disk Basic on the 26-3029 FDC to  
> > boot, and thus cannot format or other wise do anything disk  
> > related.  Is there any common issues with the FDC that I should look  
> > at to determine why the CoCo is not detecting the cartridge and  
> > booting from the FDC ROM?  The PCB for the FDC has the markings LEIA  
> > MV-1 38 84, and has the WD-1773-PH controller chip.  The markings on  
> > the ROM are TMS4764-30NL, B8428L, ZA64342, 804-5364A.
> >
> > It does not appear visually to have any burnt caps, resistors, or  
> > chips, though I have not tested any of them.  Also I have tried the  
> > time tested eraser on the contacts to see if that would resolve the  
> > problem, though I have not fully inspected the slot on the CoCo.
> >
> > Like many people before me, playing with a CoCo for the first time  
> > in their lives, help would sure be appreciated.
> >
> > Regards,
> >
> > Ryan Pritchard
> > Fun Extends All Basic Life Expectancies
> 
> 
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