[comp.sys.mac.system] Sys7 + SCSIProbe3.0 + Syquest = HANG!

jbg@wsc-sun.boeing.com (James Glidewell) (06/12/91)

A recent experience I've had may be useful to others...

My configuration -

Mac Plus
PCPC ext. 40 meg (Quantum)
APS SyQuest
System 7 (most of the time ...)
...

Both the Syquest and System 7 are new acquisitions and I've
been doing a lot of disk shuffling of Syquest cartridges.
What I found was that sometimes, for no immediately apparent
reason, dragging a syquest icon to the trash and then 
physically unmounting it caused the Mac to hang with a 
watch cursor.

I was quite puzzled by this, as I knew I had successfully
unmounted Syquest disks earlier.

The explanation came in a recent post by Malcolm Pradhan, who
mentioned that SCSI Probe 3.0 "fools" the Mac into thinking
that the Syquest was not removable (this was a "feature" for
him as he could then use the Syquest for VM).

Testing last night indicated that I could safely "trash" syquest
disks if they had been mounted with the APS PowerTools which
came with the drive. And that disks mounted with SCSI Probe 3.0
resulted in a hang. So .... 

SYQUEST USERS BEWARE -
 
DON'T ATTEMPT TO PHYSICALLY UNMOUNT SCSI PROBE 3.0 -
MOUNTED SYQUEST DISKS !!!

PS's - Does anyone know of a DA/CDEV which will mount SCSI disks which
keeps them marked as removable? Is this a bug in SCSI Probe, or was
it intentional/unavoidable? Anybody know of any SCSI-mount/unmount XCMDS? 

-- 
Jim Glidewell
jbg@wsc-sun.boeing.com
uw-beaver!bcsaic!wsc-sun!jbg

coxr@piccolo.ecn.purdue.edu (Richard L Cox) (06/13/91)

jbg@wsc-sun.boeing.com (James Glidewell) writes:

>My configuration -
>Mac Plus
>PCPC ext. 40 meg (Quantum)
>APS SyQuest
>System 7 (most of the time ...)

>What I found was that sometimes, for no immediately apparent
>reason, dragging a syquest icon to the trash and then 
>physically unmounting it caused the Mac to hang with a 
>watch cursor.

>The explanation came in a recent post by Malcolm Pradhan, who
>mentioned that SCSI Probe 3.0 "fools" the Mac into thinking
>that the Syquest was not removable (this was a "feature" for
>him as he could then use the Syquest for VM).

>Testing last night indicated that I could safely "trash" syquest
>disks if they had been mounted with the APS PowerTools which
>came with the drive. And that disks mounted with SCSI Probe 3.0
>resulted in a hang. So .... 

>SYQUEST USERS BEWARE -
> 
>DON'T ATTEMPT TO PHYSICALLY UNMOUNT SCSI PROBE 3.0 -
>MOUNTED SYQUEST DISKS !!!

I just got a Syquest and System 7 also and neither I or an associate 
of mine have had any hanging trouble with SCSI Probe mounted carts. I 
didn't even try to put the Drive Init (Extension) in and neither have
had any hangs as a result.  I flipped all three carts I have this
morining several times?  Sorry you are having trouble but you might 
have to look at some other causes.  My config is:

Mac IIci
Internal Quantum 80
Relax Syquest
System 7 (all of the time - I love it)

"And the kids they dance, they shake their bones" -GD

peace

-Rich     Internet: coxr@ecn.purdue.edu

huff@mcclb0.med.nyu.edu (Edward J. Huff) (06/17/91)

Some points regarding Syquest drives and SCSI Probe 3.0
(The reported problem was a hang upon dismount when using SCSI Probe 3.0
to mount Syquest cartridge, but not if APS Power Tools application was
used to mount the cartridge.)

1.  The exact behavior depends on the driver which the formatting
software writes on the disk.  In my experience, the first driver
loaded seems to stay around, at least judging by the Icon displayed.
I surmise that SCSI Probe just loads the driver from whatever
cartridge you insert.  Does anyone know for certain?

Therefore, it would be interesting to hear exactly which driver
James Glidewell (jbg@wsc-sun.boeing.com) was using, vs. the
driver used by Richard L. Cox (coxr@ecn.purdue.edu).

2.  By the way, some driver software is not compatible with system 7.
A long list of disk driver software was posted a few weeks back.
I have an APS drive and a Mass Microsystems drive on another system,
and I needed new software from Mass Microsystems (which they sent
free, so I finally got a little for the very inflated price I
paid a few years ago).  The APS software received early this
year is supposed to be OK.

3.  Using an earlier version of SCSI Probe and the APS driver, 
I once encountered the case where a "Please insert the disk xxx" 
modal dialog box was up, but I needed to get to the control panel 
to run SCSI Probe to mount the disk, and couldn't.  Maybe the
command key mount option of SCSI Probe 3.0 would fix this, 
I haven't tried it.  Using the Mass Micro drive with the APS
driver and SCSI Probe 3.0, leaving the Mass INIT out of the
system folder, I have been finding that the second cartridge
inserted comes up without manual intervention.

I had trouble other times if I had an application open on the
cartridge, and wanted to get some data off another cartridge.
I ejected the first, mounted the other, then got a "Please insert"
dialog, and eventually had to reset the system.  I conclude that
Syquest cartridges cannot be reliably treated "just like floppys".
Especially avoid using the eject command vs. trashing the icon.
Be sure to quit applications loaded from the cartridge before
ejecting it.

Does anyone out there really know what is going on in the
driver software?  Is the SCSI interface on all drives the
same, or do some drives need different software?  How different
are the drivers from various manufacturers?  Can I use a format
program from one manufacturer on a different manufacturer's drive?