Re: IIGS won't handle floppies

[dempson@actrix.gen.nz (David Empson)]

Vincent Quinn <gospodin@indigo.ie> wrote:

> When booted from a hard disk, my IIGS has decided it's not going to read,
> format or write to any sort of floppy disk attached to the SmartPort. SCSI
> read/writes to hard disk or Zip are fine.
> 
> If I boot the GS from a 3.5" floppy it appears to be fine and reads the
> disk with no problem - it won't format a 3.5" disk though. 

[snippages]

It sounds like a hardware problem to me.  I can't see any way in which
the SmartPort would behave as you described for software reasons, unless
you have a damaged file on your hard drive (not likely, given your
attempts to boot from other devices).

> Anyway, when booting from a hard disk, the symptoms are:
> 
> *plug in one converted Disk ][ and boot up - the machine sees two of 'em

That is probably normal - System 6.0.1 nearly always shows two drive
icons, since auto-detection of third-party drives (and some Apple
drives) is unreliable.

> *put a 3.5" disk in either drive and everything locks up - the busy light
> on the drive stays on until a forced restart

Ouch!  That could be a driver or OS problem in GS/OS, but sounds more
like a hardware problem.

> *a 5.25" disk will mount on the desktop - but if I try to format it I get
> "I/O error $27".

An I/O error could mean that writing doesn't work, or there are timing
problems accessing the drive, or something like that.  Since you said it
doesn't work when booting ProDOS-8, I'd say everything points to the IWM
chip or something in its vicinity.

> My last (forlorn?) hope that it could be software is - I'm getting a
> message I've never seen before when trying to launch some apps on the hard
> disk by double-clicking:
> Error: could not load/unload resource
> Type=8001
> ID=00005A06
> Error=1E06

That is a "resource not found" error generated by the Control Manager
when an application attempts to load a resource-based window or control
and the requested resource is not available.  In this case it is asking
for an icon with resource ID $00005A06.  An icon may be used in a dialog
box or for an icon button.

This sounds like a damaged application, or possibly the Sys.Resources
file or the Resource Manager itself has a problem (though that is an
application resource ID, not a system one).

> Also (this may be completely unrelated), if I try to open 'Control Panels'
> from the Apple menu, usually nothing happens - I have to use
> <Apple><control><escape>.

Hm, there is definitely something nasty going on.  If you have the
Control Panels NDA installed, it should open up.  This may be related to
your problem with missing resources, since the graphical Control Panels
are heavily based on resources.

> Anyone tell me what's wrong? If it's hardware, I have a scrapped //c
> motherboard - can I replace a faulty GS chip with anything on there (all
> of the //c chips except for the IWM are fine)?

No.  The IIgs and IIc have no chips in common, except for the IWM (which
is a different package type in the two machines, so isn't
interchangeable anyway, even assuming you could desolder a surface-mount
chip from the 4-layer motherboard in the IIgs, then resolder a new chip
without damaging the new chip or the motherboard).

> Alternatively, (since I have a work-around for the 5.25"s), can I leave
> the 3.5" drives attached to the PC Transporter and access them when in
> GSOS/ProDos - perhaps by patching ProDos?

You just need to install the drivers provided with the PC Transporter
(patched into the PRODOS file in the root directory).  This will let you
access the 3.5" drives, though they will be substantially slower than
when connected to the built-in disk port, and will not be compatible
with software that tries to use the hardware directly, such as Copy ][+
3.5" bit copy.

> Would they then format disks under MFM, instead of GCR?

No.  The PC Transporter can only access GCR disks in Apple 3.5 Drives
when it is acting as a disk controller for the Apple II.

It pulls some timing tricks to enable MFM disk access when running in PC
mode.  This feature isn't supported by the Apple II device driver.

> Finally, if I were to invest in a BlueDisk controller and MFM floppy
> drive(s), could I use them to access/boot from my Apple II 3.5" GCR disks?

No.  It can only support MFM 720K and higher density formats on 3.5"
disks.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand