[Coco] Booting OS9 on my CoCo 3

Arthur Flexser flexser at fiu.edu
Tue Aug 8 03:43:54 EDT 2017

Oops, I forgot that we're talking about a 3.5" drive.  But still, the fact
that you can format successfully under RSDOS only indicates that the first
35 tracks are okay.  If the drive is out of alignment, it could be having
trouble with tracks beyond the first 35.


On Tue, Aug 8, 2017 at 3:36 AM, Arthur Flexser <flexser at fiu.edu> wrote:

> Is it possible that you've configured OS-9 to expect a 40-track disk, but
> that the floppy drive you hooked up is physically not capable of 40-track
> operation? Some of the older RS drives could only handle something like 36
> tracks.  The fast seeking could be the sound of the drive vainly trying to
> access an upper track.
> Art
> On Tue, Aug 8, 2017 at 3:11 AM, Dave Philipsen <dave at davebiz.com> wrote:
>> Ok, so it's been a REAL long time since I booted OS9 on my real CoCo 3
>> from a floppy disk.  Like almost thirty years.  So I picked up a used FD501
>> controller from eBay awhile back and I just now hooked up a 3.5" floppy to
>> it.  I can format a floppy and I can save/load programs from it.  But when
>> I try to boot an old disk (probably 30 yrs old) I get the familiar "OS9
>> BOOT" screen and then the floppy does a seek at what sounds like a faster
>> step rate and then it does nothing.  Frozen with "OS9 BOOT" on the screen
>> and the floppy is still selected with the motor running.
>> This is a very old boot disk that I labeled "OS9 Level II System Master
>> with ramdisk".  My old setup was a CoCo 3 with 512K and a multipak and one
>> of the old full-size floppy controllers and an RS232 Pak.  My new setup is
>> a CoCo 3 with 128K, no MPI,  the FD501, and a 63C09.
>> I've got some 5.25" OS9 disks too but I don't currently have a 5.25"
>> drive so I'm hoping to get things worked out with the 3.5" drive. It may be
>> that the floppy is just so old it's lost some of its retentivity but I just
>> thought I'd put it out there to see if anyone has an idea.  Maybe I'm
>> missing something obvious.  The FD501 does not seem to work at hi-speed.
>> Could that be the problem?
>> Dave
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> https://pairlist5.pair.net/mailman/listinfo/coco

More information about the Coco mailing list