Apple II 3.5" Controller and SuperDrive problems...
mke...@spam.eecs.wsu.edu
Alright, I broke down a bought one of these controllers before they
disappeared off the face of the earth, mostly to replace my CPS
UDC. The CPS UDC fanned their instructions with "supports IIGS
drives and Mac externals." From reading previous documentation, I
understood that the original UniDisk 3.5 for the //e had the 6502
built onto the drive and the controller did not have one. This also
made it compatible with newer //c's.
From what I understood, one could neither connect a IIGS drive to the
UniDisk //e controller nor the //c, simply because the //e and //c
processor alone would never be able to keep up with the data stream.
This all made good sense, until I bought the Apple II 3.5" controller.
According to the controller, it has the 6502 on-board as well as the
SIWM chip. A Macintosh, similarly, has the SIWM chip on-board. I
nabbed three IIGS drives at an auction and each of them work fine
with the controller. I tested out a Mac 800K drive, which worked
fine with the CPS UDC, and it wasn't detected. I connected a bare
Macintosh SuperDrive and it wasn't detected. I then mounted the
Macintosh SuperDrive in one of the IIGS drive cases and the drive
was detected. I popped in a 720K MS-DOS and verified blocks with
Copy II Plus. No errors. I popped in a 1.44MB MS-DOS and verified
the disk with no problems. I tested out an emergency Apple II 800k
disk and it verified with no errors.
Then came the acid test. I tried formmatting a 1.44MB disk and it
gets about (what sounds like) 10 tracks into formmatting and returns
an error. Kindly the drive ejects the disk.
Suddenly things became VERY clear. Apparently the mainboard beneath
the drive (mounted inside the IIGS drive case) is handling tasks like
motor speed, and the likes, during a format command, thereby limiting
the drives capabilities.
Is there ANY way I can get the Apple II 3.5" controller to work with
the SuperDrive as a SuperDrive, aside from buying one at a ghastly
price?
I was thinking I might be able to tweak the pinouts, but after analyzing
the data carried on each of the pins I've come to the conclusion it isn't
possible.
I'm stumped. Does anyone have any recommendations?
Thanks!
/\/\ichael
replyto: mkelsey at eecs.wsu.edu
mke...@spam.eecs.wsu.edu
In article <6dg73d$b0d$1...@leopard.it.wsu.edu>,
mke...@spam.eecs.wsu.edu writes:
> Alright, I broke down a bought one of these controllers before they
> disappeared off the face of the earth, mostly to replace my CPS
> UDC. The CPS UDC fanned their instructions with "supports IIGS
[snip]
> I'm stumped. Does anyone have any recommendations?
>
> Thanks!
>
Abandon ye fears and panic yet not as thou hast discovered the tapestry
staring thy in the face!
I solved this problem, finally. Out of random luck, the first 2 1.44M and
singular 800K disks I tried failed a format, despite the fact I could read
*every* single block from the disks before and after a failed format.
I tried two more 1.44MB disks and they formmatted beautifully. Apparently
SuperDrives are quite finicky about formmatting older (used) disks!
Fancy Trick No. 7:
Format a DD disk 720K with a PC. Copy the first 64 blocks from an 800K
ProDOS formmatted disk onto the 720K disk using your Apple II. I used
ProBlock for this purpose. Next, "delete" the disk using Copy II+ and
behold as exactly 1440 blocks are free for ProDOS use!
I'm not certain what possibilities this holds, but it looks like with
careful programming, one might be able to read and write PC 1.44MB and
720K disks for file transfers...
-/\/\ichael-
replyto: mkelsey at eecs.wsu.edu
Supertimer
mke...@spam.eecs.wsu.edu wrote:
>From what I understood, one could neither connect a IIGS drive to the
>UniDisk //e controller nor the //c, simply because the //e and //c
>processor alone would never be able to keep up with the data stream.
>This all made good sense, until I bought the Apple II 3.5" controller.
Correct. When the IIc Plus came along, it was fast enough to use
the GS & Macintosh style 3.5" drives. Ironically, I am not so sure
the IIc Plus could use a UniDisk 3.5 because of this.
>I tested out a Mac 800K drive, which worked fine with the CPS UDC,
>and it wasn't detected.
If it is one of those old pre-GS Mac 800K drives without the eject
button, the CPS UDC is the only Apple II controller that can use
these drives.
>I connected a bare Macintosh SuperDrive and it wasn't detected. I
>then mounted the Macintosh SuperDrive in one of the IIGS drive
>cases and the drive was detected. I popped in a 720K MS-DOS and
>verified blocks with Copy II Plus. No errors. I popped in a 1.44MB
>MS-DOS and verified the disk with no problems. I tested out an
>emergency Apple II 800k disk and it verified with no errors.
>
>Then came the acid test. I tried formmatting a 1.44MB disk and it
>gets about (what sounds like) 10 tracks into formmatting and returns
>an error. Kindly the drive ejects the disk.
Did you format from Finder? Use Finder or another GS specific utility
because you want to use the GS/OS Apple 3.5" driver. This driver
is aware of the SuperDrive while hard coded ProDOS 8-bit utilities
may not be. ProTerm, for example, simply refuses to format a high
density disk in such a drive.
>Suddenly things became VERY clear. Apparently the mainboard beneath
>the drive (mounted inside the IIGS drive case) is handling tasks like
>motor speed, and the likes, during a format command, thereby limiting
>the drives capabilities.
Many have reported success with this method. It might just be your
formatting software.
>Is there ANY way I can get the Apple II 3.5" controller to work with
>the SuperDrive as a SuperDrive, aside from buying one at a ghastly
>price?
If you can't get it to format even with Finder or other GS specific format
utilities, just buy pre-formatted Mac or PC floppies and use the Erase
option from the Finder. It takes less than 1 second and gives you an
instant 1.44MB ProDOS disk.
Supertimer
mke...@spam.eecs.wsu.edu wrote:
(snipped portion which says you have a IIGS)
>Format a DD disk 720K with a PC. Copy the first 64 blocks from an 800K
>ProDOS formmatted disk onto the 720K disk using your Apple II. I used
>ProBlock for this purpose. Next, "delete" the disk using Copy II+ and
>behold as exactly 1440 blocks are free for ProDOS use!
Why not just format 1.44MB on the PC and "erase" the disk in the GS
Finder. That will give you 1.44MB free for ProDOS use. Ditto for 720K
format erased in the GS Finder giving you 800K.
>I'm not certain what possibilities this holds, but it looks like with
>careful programming, one might be able to read and write PC 1.44MB and
>720K disks for file transfers...
With the MS-DOS FST and the MUG! NDA, you can do this already
from the GS Finder.
Randy Shackelford
mke...@spam.eecs.wsu.edu wrote:
: I solved this problem, finally. Out of random luck, the first 2 1.44M and
: singular 800K disks I tried failed a format, despite the fact I could read
: *every* single block from the disks before and after a failed format.
: I tried two more 1.44MB disks and they formmatted beautifully. Apparently
: SuperDrives are quite finicky about formmatting older (used) disks!
That depends on the condition of the drive in question I'd say. An ultra
high mileage drive clogged with dust and the like won't fare as well as
a brand new service part for instance. I have such a drive in my Quadra
and it formats disks great; I use it for all my disk formatting, which
mainly consists of converting DOS disks into HFS disks.
: Format a DD disk 720K with a PC. Copy the first 64 blocks from an 800K
: ProDOS formmatted disk onto the 720K disk using your Apple II. I used
: ProBlock for this purpose. Next, "delete" the disk using Copy II+ and
: behold as exactly 1440 blocks are free for ProDOS use!
On an MFM disk which can't be read on a II without a superdrive card. I
think you oughtta try using a cleaning disk in your drive if it won't
format disks properly. That'll save you from going through such a senseless
rigmarole as this in all likelihood.
: I'm not certain what possibilities this holds, but it looks like with
: careful programming, one might be able to read and write PC 1.44MB and
: 720K disks for file transfers...
Not quite as easy as using HFS for sure, since that FST can write whereas
the DOS FST is read only.
--
Offsite mail to this host gets nuked.
David Empson
Supertimer <super...@aol.com> wrote:
> mke...@spam.eecs.wsu.edu wrote:
>
> >From what I understood, one could neither connect a IIGS drive to the
> >UniDisk //e controller nor the //c, simply because the //e and //c
> >processor alone would never be able to keep up with the data stream.
> >This all made good sense, until I bought the Apple II 3.5" controller.
>
> Correct. When the IIc Plus came along, it was fast enough to use
> the GS & Macintosh style 3.5" drives. Ironically, I am not so sure
> the IIc Plus could use a UniDisk 3.5 because of this.
As far as I know, it works fine. The IIc+ has special hardware support
for an Apple 3.5 Drive (including its built-in one), which basically
deals with streaming the data at higher speed than can be achieved with
a CPU loop (the Apple 3.5 Drive requires a byte to be written or read
every 16 microseconds, while the UniDisk 3.5 and any Apple II 5.25"
drive requires twice that).
The accelerated CPU in the IIc+ may have meant the special hardware was
not required after all, but it is there anyway.
The special hardware is simply not used for accessing other drive types.
>
> >I tested out a Mac 800K drive, which worked fine with the CPS UDC,
> >and it wasn't detected.
>
> If it is one of those old pre-GS Mac 800K drives without the eject
> button, the CPS UDC is the only Apple II controller that can use
> these drives.
The main reason for this is minor differences in the control signals,
which are dealt with by the interface board in the Apple 3.5 Drive.
> >I connected a bare Macintosh SuperDrive and it wasn't detected. I
> >then mounted the Macintosh SuperDrive in one of the IIGS drive
> >cases and the drive was detected. I popped in a 720K MS-DOS and
> >verified blocks with Copy II Plus. No errors. I popped in a 1.44MB
> >MS-DOS and verified the disk with no problems. I tested out an
> >emergency Apple II 800k disk and it verified with no errors.
> >
> >Then came the acid test. I tried formmatting a 1.44MB disk and it
> >gets about (what sounds like) 10 tracks into formmatting and returns
> >an error. Kindly the drive ejects the disk.
>
> Did you format from Finder? Use Finder or another GS specific utility
> because you want to use the GS/OS Apple 3.5" driver. This driver
> is aware of the SuperDrive while hard coded ProDOS 8-bit utilities
> may not be. ProTerm, for example, simply refuses to format a high
> density disk in such a drive.
This is certainly possible, but if the disk has the high density
detection hole (as it should), then the firwmare should automatically
use the correct format. Some programs make assumptions about the disk
capacity, and have problems dealing with unexpected sizes.
There is an extra call in the SuperDrive card's firmware which specifies
the formatting method. If this is not used, the card determines the
format automatically according to the disk type.
> >Suddenly things became VERY clear. Apparently the mainboard beneath
> >the drive (mounted inside the IIGS drive case) is handling tasks like
> >motor speed, and the likes, during a format command, thereby limiting
> >the drives capabilities.
Not exactly. The motor speed is fixed when the drive is being used with
an MFM disk (720K or 1440K), and the variable speed is handled
automatically by the drive mechanism for GCR disks (400K and 800K).
I would have expected this combination to work fine, as others have done
this.
--
David Empson
dem...@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand
GR1071
Maybe, this will help with which drives will work with which computers:
name--------works on------works on-----works with------works on IIgs
II,II+,IIe IIc IIgs Smartport Internal
Slot
------------------------------------------------------------ --------
Unidisk 3.5 Yes *,^ Yes Yes Yes
*
Apple 3.5 Yes * No Yes Yes
*
Mac 400K Yes * No No Yes
*
Mac 800K Yes * No No Yes *
Disk II Yes *,@ Yes $ Yes $ Yes *,@
Apple 5.25 Yes *,% Yes Yes Yes *,%
Unidisk 5.25 Yes *,% Yes Yes Yes *,%
Disk IIc Yes *,% Yes Yes Yes *,%
DuoDisk Yes *,% 1st dr only Yes Yes *,%
Key.. YES Means Yes... Yes with any modifiers means that it REQUIRES one of
the modifiers.. No Means no... Modifiers follow
^ --- Apple 3.5 Drive Controller
* --- Universal Drive Controller (UDC)
@ --- Disk II Controller Card
$ --- DB-19 Adapter Cable
% --- Apple 5.25 Drive Controller Card
I hope this helps.
Lee
mke...@spam.eecs.wsu.edu
In article <19980304062...@ladder03.news.aol.com>,
super...@aol.com (Supertimer) writes:
> mke...@spam.eecs.wsu.edu wrote:
>
> (snipped portion which says you have a IIGS)
Sadly, I do not. I have a //e =)
> Why not just format 1.44MB on the PC and "erase" the disk in the GS
> Finder. That will give you 1.44MB free for ProDOS use. Ditto for 720K
> format erased in the GS Finder giving you 800K.
Apple II Desktop 1.1 doesn't allow for block specifications. What I
format is dependent on the floppy media. If it is a DD it is formmatted
as 800k, if it is HD it goes as 1.44MB. If I insert a PC 720k and
format, it turns into an 800k. If I copy bocks from the 800k onto the
720k and then "delete" as opposed to format, the disk will become a
720k Apple II ProDOS formatted disk! Just a useless fact.
> With the MS-DOS FST and the MUG! NDA, you can do this already
> from the GS Finder.
Again, I don't have a GS.
mke...@spam.eecs.wsu.edu
In article <19980304050...@ladder03.news.aol.com>,
>>UniDisk //e controller nor the //c, simply because the //e and //c
>>processor alone would never be able to keep up with the data stream.
>>This all made good sense, until I bought the Apple II 3.5" controller.
> Correct. When the IIc Plus came along, it was fast enough to use
> the GS & Macintosh style 3.5" drives. Ironically, I am not so sure
> the IIc Plus could use a UniDisk 3.5 because of this.
My suspicions were correct about the Apple 3.5" Drive mainboard. It looks
as though the mainboard inside the drive itself sends out the signal to
identify the drive as an Apple II (and GS) peripheral, of which the Apple
3.5" Drive controller will recognize. That and I believe the main-
board inside the drive case (I should have been more specific) also sends
a signal to the drive when the eject button is pressed, whereas on a Mac-
intosh, this situation is never encountered.
What I'm wondering now, is if I place a logic high on the Apple 3.5" drive
"pin" if the Apple II 3.5" drive controller will recognize the drive in
a Macintosh 800K external drive case, e.g. bare drive without any logic
board sitting underneath?
The strange part is that on my Central Point UDC (remember, I have a //e)
it polled the drives in Apple II Desktop. With the Apple II 3.5" Drive
controller, the drives are not continually polled, and instead, when I
inject or eject a disk, the Desktop updates. Next, if I drag the disk
onto the trash, it treats it just like a 5.25" and re-reads the disk
without ejecting. With the Central Point UDC, I could drag disks onto
the trash and they would eject. This worked very nicely with my Macintosh
External 400K and 800K drives, as they don't have an eject button.
It's not as though I'm concerned about losing this functionality. By
seating the SuperDrive in the IIgs external drive case, I have gained
the ability to eject the disk anytime I feel like it. Plus, the drives
aren't continually being polled either! Maybe the 32k SRAM on the
controller prevents this from happening? I will have to investigate
this further.
>>I tested out a Mac 800K drive, which worked fine with the CPS UDC,
>>and it wasn't detected.
>
> If it is one of those old pre-GS Mac 800K drives without the eject
> button, the CPS UDC is the only Apple II controller that can use
> these drives.
Right, I am guessing this must be because of the "Apple 3.5 Drive"
signal introduced when the IIgs came into being. I wonder if it would
be possible to "fool" a controller by giving it that signal from a
bare drive?
> Did you format from Finder? Use Finder or another GS specific utility
> because you want to use the GS/OS Apple 3.5" driver. This driver
> is aware of the SuperDrive while hard coded ProDOS 8-bit utilities
> may not be. ProTerm, for example, simply refuses to format a high
> density disk in such a drive.
I don't have a "Finder" for my //e, although I do have Apple II Desktop.
Apple II Desktop (MouseDesk) allows the drive to tell *it* what to do.
If the disk is high-density, ProDOS will format high-density. If the
disk is double-density, it gets formmated 800k. I would be curious
to know how to format the disk 720k, if anyone has any information on
this. Maybe there's some undocumented commands when making a ProDOS
format call...time to dig up "Beneath Apple ProDOS."
>>Suddenly things became VERY clear. Apparently the mainboard beneath
>>the drive (mounted inside the IIGS drive case) is handling tasks like
>>motor speed, and the likes, during a format command, thereby limiting
>>the drives capabilities.
>
> Many have reported success with this method. It might just be your
> formatting software.
Actually, I just had random bad luck. Two high density disks I tested
and one double density all verified with reading blocks with no lag
or errors. I even tried writing to the blocks that "failed" during
the format and ran into no problems. The next evening I took an old
ABIT Flash Bios disk, formmatted it, and suddenly I had a 1.44MB
ProDOS volume. It works great, so long as the disks aren't getting
"old." I tried several other disks, too, and they worked fine. I also
verified the other disks were bad by attempting a format in a PC. They
failed.
> If you can't get it to format even with Finder or other GS specific format
> utilities, just buy pre-formatted Mac or PC floppies and use the Erase
> option from the Finder. It takes less than 1 second and gives you an
> instant 1.44MB ProDOS disk.
I tried that the evening before I discovered it was a disk problem. I took
a PC 1.44MB disk, copied blocks over from an 800k to make a "valid" ProDOS
volume, and "deleted" the disk using Copy II+. It must be very nice having
a finder to choose the desired format ;) Maybe I'll write one for my //e.
Fortunately the Apple II 3.5" Controller is "smart" and knows when I've
inserted the appropriate media.
Randy Shackelford
Supertimer (super...@aol.com) wrote:
[snip]
: Why not just format 1.44MB on the PC and "erase" the disk in the GS
: Finder. That will give you 1.44MB free for ProDOS use. Ditto for 720K
: format erased in the GS Finder giving you 800K.
This works on HD disks but you get a "disk write protected" error on DD
disks. You can't simply erase 720K MFM disks into 800K GCR disks, it takes
a reformat.
Supertimer
mke...@spam.eecs.wsu.edu wrote:
>I tried that the evening before I discovered it was a disk problem. I took
>a PC 1.44MB disk, copied blocks over from an 800k to make a "valid" ProDOS
>volume, and "deleted" the disk using Copy II+. It must be very nice having
>a finder to choose the desired format ;) Maybe I'll write one for my //e.
>Fortunately the Apple II 3.5" Controller is "smart" and knows when I've
>inserted the appropriate media.
I'm sorry about misreading the part about you having a GS, but fear not!
Did you know there is an 8-bit Apple II program that can read MS-DOS
files off a SuperDrive? If you are interested, I can look in my list of
programs and post it to cba2 and the ftp servers. Let me know...
Supertimer
sh...@onyx.southwind.net (Randy Shackelford) wrote:
You're right, but you know what? I once managed to format a 720K MFM
ProDOS disk. I forgot what utilities I used or what I did, but it worked and
the GS saw the disk. Does anyone know how I did it so that I can reclaim
the knowledge?
David Empson
GR1071 <gr1...@aol.com> wrote:
> Maybe, this will help with which drives will work with which computers:
It is a good start. Unfortunately, the table was formatted so badly I
had to tidy it up before I could read it (you shouldn't have used tabs,
and some of the columns weren't lined up anyway).
Here it is cleaned up, but I have several points to correct:
name--------works on------works on-----works with------works on IIgs
II,II+,IIe IIc IIgs Smartport Internal Slot
--------------------------------------------------------------------
Unidisk 3.5 Yes *,^ Yes Yes Yes *,^
Apple 3.5 Yes * No Yes Yes *
Mac 400K Yes * No No Yes *
Mac 800K Yes * No No Yes *
Disk II Yes *,@ Yes $ Yes $ Yes *,@
Apple 5.25 Yes *,% Yes Yes Yes *,%
Unidisk 5.25 Yes *,% Yes Yes Yes *,%
Disk IIc Yes *,% Yes Yes Yes *,%
DuoDisk Yes *,% 1st dr only Yes Yes *,%
Key.. YES Means Yes... Yes with any modifiers means that it REQUIRES one
of the modifiers.. No Means no... Modifiers follow
^ --- Apple 3.5 Drive Controller
* --- Universal Drive Controller (UDC)
@ --- Disk II Controller Card
$ --- DB-19 Adapter Cable
% --- Apple 5.25 Drive Controller Card
Points:
1. By "Apple 3.5 Drive Controller" I assume you mean the "Apple 3.5
Floppy Disk Drive Interface Card" (aka "Liron"). This card only
supports the UniDisk 3.5 drive, and it does NOT work in a IIgs.
2. You didn't mention the "Apple II 3.5 Disk Controller Card" (aka
"SuperDrive Card"). This card requires a IIgs or enhanced IIe, though
it may work in a II or II+ which has a 65C02 or ZIP chip. The card
supports the UniDisk 3.5, Apple 3.5 Drive and SuperDrive. It is the
only card that allows a SuperDrive to access 720K and 1440K disks.
3. For the UniDisk 3.5 to work on the IIc, the IIc must have ROM version
0, 3 or 4. ROM version 255 must be upgraded.
4. I don't think the UniDisk 3.5 is supported by the Universal Disk
Controller. (I haven't verified this myself, but I've heard it from
others several times.)
5. No mention of the IIc+, which has a built-in 3.5 drive and will
support the Apple 3.5 Drive, and can use both drives in a DuoDisk
(otherwise matches a IIc).
6. No mention of the SuperDrive, which has two levels of compatibility:
Apple 3.5 emulation (same rules as Apple 3.5), and native, which
requires the "Apple II 3.5 Disk Controller Card".
7. In some cases the DuoDisk has problems on the IIgs, and requires a
hardware modification. (I don't have the details handy.)
8. No mention of drive order requirements and limits to the number of
each drive which may be connected. In general: Apple 3.5 (maximum of
two per controller) first, then UniDisk 3.5 (no hard limit on the
number), then 5.25" drives (maximum of two per controller). You
shouldn't have more than four drives connected to any one drive port.
In the case of the IIc, there can only be one external 5.25" drive
(which must be at the end of the chain).
9. No mention of the Chinook/Sequential SmartPort hard drives (same
compatibility as the UniDisk 3.5).
10. No mention of the PC Transporter, which can act as a controller for
the Apple 3.5 Drive (albeit not very well) in a II, II+, IIe or IIgs.
11. No mention of the Applied Engineering 3.5" drives. The 800K one is
basically compatible with the Apple 3.5 Drive, and there is also a high
density one (1600K format) which only works on the IIgs built-in port,
and then only with a special driver. (I believe this is the case - can
anyone else confirm or deny?)
12. All the UniDisk-style 5.25" drives can be used on a Disk ][
controller card with an adaptor cable.
13. The Mac HD20 drive doesn't work with any of these controller options
(only on a Mac).
I haven't even considered other floppy drive types (e.g. MFM) - I'd be
here all night, and they usually need different controllers anyway. :-)
Did I miss anything?
Does someone want to construct a new table which incorporates all of
this? :-)
David Empson
<mke...@spam.eecs.wsu.edu> wrote:
> What I'm wondering now, is if I place a logic high on the Apple 3.5" drive
> "pin" if the Apple II 3.5" drive controller will recognize the drive in
> a Macintosh 800K external drive case, e.g. bare drive without any logic
> board sitting underneath?
This might work, but I haven't investigated closely, so I can't be sure.
> The strange part is that on my Central Point UDC (remember, I have a //e)
> it polled the drives in Apple II Desktop. With the Apple II 3.5" Drive
> controller, the drives are not continually polled, and instead, when I
> inject or eject a disk, the Desktop updates.
You will probably find that Apple II Desktop _is_ polling the drives,
but the poll is so short you cannot see it. The UDC might be spinning
the drive up just to read the disk changed detector.
The IIgs Finder does poll Apple 3.5 drives, but the light blink is so
short you have to look very closely to see it.
> Next, if I drag the disk onto the trash, it treats it just like a 5.25"
> and re-reads the disk without ejecting. With the Central Point UDC, I
> could drag disks onto the trash and they would eject. This worked very
> nicely with my Macintosh External 400K and 800K drives, as they don't have
> an eject button.
Hm, not sure about that one. Possibly a compatibility problem, as Apple
II Desktop predates Apple's newer controller card, and might not
recognise it properly.
> I don't have a "Finder" for my //e, although I do have Apple II Desktop.
> Apple II Desktop (MouseDesk) allows the drive to tell *it* what to do.
> If the disk is high-density, ProDOS will format high-density. If the
> disk is double-density, it gets formmated 800k. I would be curious
> to know how to format the disk 720k, if anyone has any information on
> this. Maybe there's some undocumented commands when making a ProDOS
> format call...time to dig up "Beneath Apple ProDOS."
I had limited success getting the SuperDrive card to reliably format
720K disks. I suspect it has a firmware bug. The only way that
appeared to work was to format a 720K disk immediately after another one
was inserted. I actually got machine crashes in some cases.
The ProDOS format call is not flexible enough to let the application
choose the format. You have to use the SmartPort calls, and the
SuperDrive card implements a new call that was introduced with the ROM 3
IIgs. The 'SetFormatOptions' call is documented in the ROM 3 supplement
to the IIgs Firmware Reference.
GR1071
> Maybe, this will help with which drives will work with which >computers:
>It is a good start. Unfortunately, the table was formatted so badly I
>had to tidy it up before I could read it (you shouldn't have used tabs,
>and some of the columns weren't lined up anyway).
<snip>
>4. I don't think the UniDisk 3.5 is supported by the Universal Disk
>Controller. (I haven't verified this myself, but I've heard it from
>others several times.)
I will verify that it DOES work. I should have prefaced the chart by saying
that it was from the 1986-1988 era. Hence, no mention of 1.44 drives, etc.
Sorry for the confusion. But I would like to update the chart.
Lee G
pub...@library.ucla.edu
David Empson wrote:
> 11. No mention of the Applied Engineering 3.5" drives. The 800K one is
> basically compatible with the Apple 3.5 Drive, and there is also a high
> density one (1600K format) which only works on the IIgs built-in port,
> and then only with a special driver. (I believe this is the case - can
> anyone else confirm or deny?)
I can confirm this. I have a later model AE FDHD and it works
as a 1.44MB drive with the SuperDrive controller. Older model
AE FDHDs work as 1.6MB GCR drives connected to the IIgs built-in
port, but only as 800K drives when connected to the SuperDrive
controller. The 1.6MB format requires the AE driver, which can
be found on ground. The driver only works with older model
AE FDHDs.
> 13. The Mac HD20 drive doesn't work with any of these controller options
> (only on a Mac).
Wrong, the UDC works with the Mac HD20. I've seen one attached
to an Apple IIe. There are two models of UDC cards. One is the
older full size controller. The second one is the newer, half
size card. The IIe that was connected to the HD20 used the full
sized version. I would think that the half sized card would
retain the capability.
-Scott G.
Mitchell Spector
In article super...@aol.com (Supertimer) writes...
>Correct. When the IIc Plus came along, it was fast enough to use
>the GS & Macintosh style 3.5" drives.
Increased speed was only part of the reason--it also had some
extra circuitry added to the motherboard to help deal with data
flow from an Apple 3.5 drive. There is the equivalent of a ZipChip
built-in to the IIc Plus, and it takes more than just adding one
of those to make the machine get along with "dumb" floppies drive.
>Ironically, I am not so sure the IIc Plus could use a UniDisk 3.5
>because of this.
The IIc Plus handles the UniDisk 3.5 just fine, as well as the
Apple 3.5 and Apple SuperDrive (the latter will work only in 800K
mode though, you cannot use it with high density disks or make use
of its MFM capabilities).
Mitchell Spector
sp...@vax2.concordia.ca
pub...@library.ucla.edu
Mitchell Spector wrote:
>
> In article super...@aol.com (Supertimer) writes...
>
> >Correct. When the IIc Plus came along, it was fast enough to use
> >the GS & Macintosh style 3.5" drives.
>
> Increased speed was only part of the reason--it also had some
> extra circuitry added to the motherboard to help deal with data
> flow from an Apple 3.5 drive. There is the equivalent of a ZipChip
> built-in to the IIc Plus, and it takes more than just adding one
> of those to make the machine get along with "dumb" floppies drive.
Actually, no. The increased speed would have enabled it to work
with the drives (you'd have to give it a GS IWM and take out all
the UniDisk junk first, though). The high speed Laser computers
handle Apple 3.5 drives just fine and they do it faster than a
UDC (which needs extra circuitry for the slow 1MHz of the IIe).
The reason the IIc Plus has extra circuitry is because the logic
board still runs at 1MHz and that's because Apple originally
designed it as a 1MHz computer. Later, as a second thought, they
added in the equivalent of a ZipChip (licensed firmware and
caching technology, even though the SRAM cache is separate in the
IIc Plus). They already made most of the logic board work with
1MHz in mind, so in order to add speed they had to go the cache
accelerator method. Kinda crazy, if you ask me. They should
have had extra speed in mind first and made the entire logic
board go at 4MHz, like the Laser computers do. If the logic
board operated at 4MHz, direct Apple 3.5 drive usage, like on
the IIgs, would be possible.
-Scott G.
Mitchell Spector
In article dem...@actrix.gen.nz (David Empson) writes...
>3. For the UniDisk 3.5 to work on the IIc, the IIc must have ROM version
>0, 3 or 4. ROM version 255 must be upgraded.
It also functions with ROM version 5--the Apple IIc Plus.
>4. I don't think the UniDisk 3.5 is supported by the Universal Disk
>Controller. (I haven't verified this myself, but I've heard it from
>others several times.)
I believe certain versions of the UDC board supported it, while
others did not due to either firmware or hardware changes. I recall
it being the former based on a discussion in this group awhile ago.
>5. No mention of the IIc+, which has a built-in 3.5 drive and will
>support the Apple 3.5 Drive, and can use both drives in a DuoDisk
>(otherwise matches a IIc).
As mentioned above, it also supports the UniDisk 3.5 drive, not
too mention the Apple SuperDrive in 800K emulation mode (of course
neither type of drive deserves to be wasted on a IIc Plus when it
works with the Apple 3.5 just fine).
>7. In some cases the DuoDisk has problems on the IIgs, and requires a
>hardware modification. (I don't have the details handy.)
I still stick to the belief the ROM 3 IIgs is not compatible with
the DuoDisk, based on my own personal experience and Apple discussion
notes (in the Apple Tech Info Library) stating compatibility issues
are a problem. Stephen Buggie claims his DuoDisk works from his ROM 3
IIgs, although I'm not sure if he modified the drive or not.
The hardware modification (involved clipping some components off
the analog board) was to reduce power consumption so it could work
when daisy-chained from the IIgs's disk port. Apple came up with the
fix well before the ROM 3 motherboard was even conceived and offered
no solution years later--except to use a slot based controller card
or avoid using the drive altogether.
>11. No mention of the Applied Engineering 3.5" drives. The 800K one is
>basically compatible with the Apple 3.5 Drive, and there is also a high
>density one (1600K format) which only works on the IIgs built-in port,
>and then only with a special driver. (I believe this is the case - can
>anyone else confirm or deny?)
From what I recall, the so-called 1600K AE FDHD 3.5 drive was
a SuperDrive clone with a lesser version of the Sony mechanism.
With AE's GS/OS driver, you could use a proprietary 1.6 MB format
on the GS (at least for data storage, don't think it could boot).
There may have been extra circurity inside, as I'm not so sure
you could connect an official Apple SuperDrive to the back of the
IIgs and read/write 1600K floppies using AE's GS/OS driver. I also
remember AE selling the same drive to the Amiga community with a
special driver to do a proprietary 1.7 MB format.
Mitchell Spector
sp...@vax2.concordia.ca
Jeff Blakeney
On 4 Mar 1998 05:08:35 GMT, super...@aol.com (Supertimer) wrote:
[snip]
>If you can't get it to format even with Finder or other GS specific format
>utilities, just buy pre-formatted Mac or PC floppies and use the Erase
>option from the Finder. It takes less than 1 second and gives you an
>instant 1.44MB ProDOS disk.
Are you sure about this? It seems to me that if the disk isn't
initialized as a ProDOS disk, erasing it should give you an error.
Especially if you try to erase a 720k MFM disk into an 800k GCR. It
just ain't gonna happen.
I'm just curious as to whether you are indeed erasing an MS-DOS
formatted disk into a ProDOS disk because, as far as I know, it is
impossible.
=== I've had enough SPAM. Cut the obvious from my address to email me. ===
Randy Shackelford
Jeff Blakeney (CUTj...@bconnex.net) wrote:
: Are you sure about this? It seems to me that if the disk isn't
: initialized as a ProDOS disk, erasing it should give you an error.
: Especially if you try to erase a 720k MFM disk into an 800k GCR. It
: just ain't gonna happen.
Righto, that doesn't work.
: I'm just curious as to whether you are indeed erasing an MS-DOS
: formatted disk into a ProDOS disk because, as far as I know, it is
: impossible.
I wasn't aware that this would work until I tried it the other day. But it
really does work for HD disks.
Supertimer
CUTj...@bconnex.net (Jeff Blakeney) wrote:
>On 4 Mar 1998 05:08:35 GMT, super...@aol.com (Supertimer) wrote:
>
>[snip]
>>If you can't get it to format even with Finder or other GS specific format
>>utilities, just buy pre-formatted Mac or PC floppies and use the Erase
>>option from the Finder. It takes less than 1 second and gives you an
>>instant 1.44MB ProDOS disk.
>
>Are you sure about this? It seems to me that if the disk isn't
>initialized as a ProDOS disk, erasing it should give you an error.
>Especially if you try to erase a 720k MFM disk into an 800k GCR. It
>just ain't gonna happen.
You are right that you can't erase a 720K MFM disk into an 800K
GCR disk. You can, however, erase a 1.44MB MFM disk into a
1.44MB MFM disk, which is what is happening with a ProDOS
erase of an MS-DOS disk.
>I'm just curious as to whether you are indeed erasing an MS-DOS
>formatted disk into a ProDOS disk because, as far as I know, it is
>impossible.
It is possible and I do it all the time. I have four boxes of Gold Seal
Quality Certified Premium 3.5" DS/HD Diskettes Formatted IBM
1.44MB that I use by erasing them to ProDOS of HFS.
David Empson
<pub...@library.ucla.edu> wrote:
> David Empson wrote:
> > 13. The Mac HD20 drive doesn't work with any of these controller options
> > (only on a Mac).
>
> Wrong, the UDC works with the Mac HD20. I've seen one attached
> to an Apple IIe. There are two models of UDC cards. One is the
> older full size controller. The second one is the newer, half
> size card. The IIe that was connected to the HD20 used the full
> sized version. I would think that the half sized card would
> retain the capability.
I've seen what is presumably the half sized one, but unfortunately it
was damaged, so I've never been able to use a working one.
Regarding the UniDisk 3.5 on the UDC: I could have sworn that I've had
reports from some people that this combination did NOT work. Perhaps it
is possible that the newer version of the UDC does not support the
UniDisk 3.5, while the older one did work. Another possibility is that
it might have been broken for one firmware version.
Can anyone else out there confirm that they have failed to get a UniDisk
3.5 working on a UDC? If so, can you please let us know which UDC
version it was, and any other identifying characteristics.
David Wilson
dem...@actrix.gen.nz (David Empson) writes:
>Can anyone else out there confirm that they have failed to get a UniDisk
>3.5 working on a UDC? If so, can you please let us know which UDC
>version it was, and any other identifying characteristics.
My UDC works well with Apple 3.5, slowly with Mac 800K, not at all with
a UniDisk 3.5 and not at all with a Mac 400K (although that could have been
that the 400K drive was faulty).
The UDC is a small card with 2x 19pin D type connectors on 2 ribbon cables.
I disassembled the code to patch it so that 5.25" drives are treated as 40
track devices without patching ProDOS. Looking at the listing I only see
mention of DISK 5.25 and DISK 3.5 so if the UDC ever had support for the HD20
it was dropped by the time my card was built.
--
David Wilson School of IT & CS, Uni of Wollongong, Australia da...@uow.edu.au
mke...@spam.eecs.wsu.edu
In article <1d5hs41.1qh...@dempson.actrix.gen.nz>,
dem...@actrix.gen.nz (David Empson) writes:
> <mke...@spam.eecs.wsu.edu> wrote:
>
> This might work, but I haven't investigated closely, so I can't be sure.
I intend to test this theory out. I believe this would be a safe means
for Apple to have ensured that a //e user's disk wouldn't be trapped in
the drive and force the user to eject the disk manually. It would make
sense as to why the "Apple 3.5" Drive" pin was needed.
I'm just guessing at this, but I believe that the mainboard on the inside
of the drive housing is actually a bridge between the 800K or SuperDrive
to enable drive eject and designate the drive as an Apple II viable
drive. Again, this is just a theory that I hope to prove correct
later on.
One thing that Apple II 3.5" Drive controller states in the manual is
that it is equipped with a 6502 and the SIWM chipset. The Macintosh
(older models) had at least the SIWM chipset on board. Granted, the
operating system handled disk inject/eject sequences, but it leads me
to believe that in all reality, the mainboard underlying the drive in
the IIgs housing is a "friendly" interface designed to facilitate older
equipment.
> You will probably find that Apple II Desktop _is_ polling the drives,
> but the poll is so short you cannot see it. The UDC might be spinning
> the drive up just to read the disk changed detector.
Ummm. I will have to look at this. I know the CPS UDC "disabled" the
eject button the IIgs drives. When Apple II Desktop wasn't running I could
eject the disks with the button. It was almost like with Linux, where
after mounting a CD-ROM, it activates the "lock" function, keeping the
CD-ROM disc in the drive until the device is unmounted.
The IIgs drives connected through the Apple II 3.5 Drive controller always
allow for the disk to be ejcted.
> The IIgs Finder does poll Apple 3.5 drives, but the light blink is so
> short you have to look very closely to see it.
I remember using Apple II Desktop on a IIgs and when it polled the drives
you did have to look very closely at drive lights. You could certainly
see them flash. I have looked closely when my //e is running Apple II
Desktop and there isn't an obvious flicker like with the IIgs or when
my CPS UDC was being polled.
I am beginning to think the 32K of SRAM cache on the Apple II 3.5" Drive
controller keeps the 3.5" from being accessed during frequent polling.
>> Next, if I drag the disk onto the trash, it treats it just like a 5.25"
>> and re-reads the disk without ejecting. With the Central Point UDC, I
>> could drag disks onto the trash and they would eject. This worked very
>> nicely with my Macintosh External 400K and 800K drives, as they don't have
>> an eject button.
>
> Hm, not sure about that one. Possibly a compatibility problem, as Apple
> II Desktop predates Apple's newer controller card, and might not
> recognise it properly.
That would make me think that the Apple II Desktop would treat the disks
just as it treats my QRAM //e volume, with a "hard drive" icon. Instead
it places a 3.5" icon for any of the disks. Perhaps Apple II Desktop
identifies the controller as a smart port, but doesn't know quite what
to do beyond that. I know for a fact that Apple II Desktop on a IIgs
would eject the disks when dragged onto the trash. Therefore, it leads
me to believe that Apple II 3.5" Drive controller is identified as a
smart port, but not as a smart port that Apple II Desktop recognizes.
> I had limited success getting the SuperDrive card to reliably format
> 720K disks. I suspect it has a firmware bug. The only way that
> appeared to work was to format a 720K disk immediately after another one
> was inserted. I actually got machine crashes in some cases.
The only way I have found to format 720K disks on my //e is to take a
blank MS-DOS 720K disk, copy blocks over from any other ProDOS volume
to make an identifiable "ProDOS" volume, and then erase (not format)
the volume with Copy II+. Somehow when Copy II+ erases the disk, it
queries the device as to the size and writes the appropriate table.
Note that an erase of the disks will only erase the first few blocks
on the disk and leaves the remaining sectors unscathed.
> The ProDOS format call is not flexible enough to let the application
> choose the format. You have to use the SmartPort calls, and the
> SuperDrive card implements a new call that was introduced with the ROM 3
> IIgs. The 'SetFormatOptions' call is documented in the ROM 3 supplement
> to the IIgs Firmware Reference.
So essentially I'd have to "detect" the firmware by scanning and then
program the controller to format 720K. After that I would make a ProDOS
format call and all my request should be carried out?
mke...@spam.eecs.wsu.edu
In article <1d5kp6z.kj...@dempson.actrix.gen.nz>,
dem...@actrix.gen.nz (David Empson) writes:
> <pub...@library.ucla.edu> wrote:
>
>> Wrong, the UDC works with the Mac HD20. I've seen one attached
>> to an Apple IIe. There are two models of UDC cards. One is the
>> older full size controller. The second one is the newer, half
>> size card. The IIe that was connected to the HD20 used the full
>> sized version. I would think that the half sized card would
>> retain the capability.
So what exactly is the Mac HD20? Is this just an external SuperDrive?
I have connected a SuperDrive to my CPS UDC (half-sized I'm guessing)
but it only recognized the drive as an 800K which I believe to be
a limitation of the firmware, but perhaps in the hardware, as well.
> Can anyone else out there confirm that they have failed to get a UniDisk
> 3.5 working on a UDC? If so, can you please let us know which UDC
> version it was, and any other identifying characteristics.
If I had a UniDisk 3.5, I'd test this out. Unfortunately, I don't think
a Macintosh external is the same thing. In fact, I distinctly recall
the the UniDisk 3.5 having a 6502 built into the drive case.
mke...@spam.eecs.wsu.edu
In article <19980307074...@ladder03.news.aol.com>,
super...@aol.com (Supertimer) writes:
> CUTj...@bconnex.net (Jeff Blakeney) wrote:
>
>>On 4 Mar 1998 05:08:35 GMT, super...@aol.com (Supertimer) wrote:
>>
>>[snip]
> GCR disk. You can, however, erase a 1.44MB MFM disk into a
> 1.44MB MFM disk, which is what is happening with a ProDOS
> erase of an MS-DOS disk.
Now this must be some characteristic of the Apple IIgs operating
system. If I attempt to erase (not format) an MS-DOS 1.44MB disk
with Copy II+ it reports "not a ProDOS disk," and quits.
--
-/\/\ichael-
mke...@spam.eecs.wsu.edu
In article <35009af5...@news.bconnex.net>,
CUTj...@bconnex.net (Jeff Blakeney) writes:
> On 4 Mar 1998 05:08:35 GMT, super...@aol.com (Supertimer) wrote:
>
> [snip]
>>utilities, just buy pre-formatted Mac or PC floppies and use the Erase
>>option from the Finder. It takes less than 1 second and gives you an
>>instant 1.44MB ProDOS disk.
>
> Are you sure about this? It seems to me that if the disk isn't
> initialized as a ProDOS disk, erasing it should give you an error.
> Especially if you try to erase a 720k MFM disk into an 800k GCR. It
> just ain't gonna happen.
>
> formatted disk into a ProDOS disk because, as far as I know, it is
> impossible.
Well, as I stated earlier, I wrote over the first few blocks of the
720K MS-DOS disk with another ProDOS volume. This allowed Copy II
Plus to believe the volume was in fact a ProDOS disk. After that I
used the equivalent of a "quick-format" by erasing the ProDOS disk.
When Copy II+ erases a disk, it appears to query the controller
about the device size so it can write the proper file block table.
In my case, the Apple II 3.5" Drive controller detects the disk as
being a 720K MFM format and reports to ProDOS the 720K volume size.
Copy II+ Plus receives this information and writes the proper volume
table. I highly doubt the firmware on the card contains information
about what to write for ProDOS in each circumstance, but perhaps I
am wrong.
--
Randy Shackelford
mke...@spam.eecs.wsu.edu wrote:
: I'm just guessing at this, but I believe that the mainboard on the inside
: of the drive housing is actually a bridge between the 800K or SuperDrive
: to enable drive eject and designate the drive as an Apple II viable
: drive. Again, this is just a theory that I hope to prove correct
: later on.
Yep, the daisychain logic board works the in use light and eject button,
allows daisychaining, and lets a IIgs and //c plus recognize it. Take it
out and you have the beige 800K essentially.
: One thing that Apple II 3.5" Drive controller states in the manual is
: that it is equipped with a 6502 and the SIWM chipset. The Macintosh
: (older models) had at least the SIWM chipset on board. Granted, the
: operating system handled disk inject/eject sequences, but it leads me
: to believe that in all reality, the mainboard underlying the drive in
: the IIgs housing is a "friendly" interface designed to facilitate older
: equipment.
Don't forget a 14 MHz oscillator which the SWIM needs to function.
: That would make me think that the Apple II Desktop would treat the disks
: just as it treats my QRAM //e volume, with a "hard drive" icon. Instead
: it places a 3.5" icon for any of the disks. Perhaps Apple II Desktop
: identifies the controller as a smart port, but doesn't know quite what
: to do beyond that. I know for a fact that Apple II Desktop on a IIgs
: would eject the disks when dragged onto the trash. Therefore, it leads
: me to believe that Apple II 3.5" Drive controller is identified as a
: smart port, but not as a smart port that Apple II Desktop recognizes.
Apple II Desktop uses a primitive, no longer supported device identification
process, namely the device ID nibble for each device in the device list.
Change the value for a device and you change the icon that appears.
: The only way I have found to format 720K disks on my //e is to take a
: blank MS-DOS 720K disk, copy blocks over from any other ProDOS volume
: to make an identifiable "ProDOS" volume, and then erase (not format)
: the volume with Copy II+. Somehow when Copy II+ erases the disk, it
: queries the device as to the size and writes the appropriate table.
: Note that an erase of the disks will only erase the first few blocks
: on the disk and leaves the remaining sectors unscathed.
I wrote a program which writes a ProDOS directory and bit map to any disk
which can physically be written to. I call it a pseudoformat. Never tried
it on a 720K, I'll give it a try next time I have the IIgs on.
Randy Shackelford
mke...@spam.eecs.wsu.edu wrote:
: So what exactly is the Mac HD20? Is this just an external SuperDrive?
: I have connected a SuperDrive to my CPS UDC (half-sized I'm guessing)
: but it only recognized the drive as an 800K which I believe to be
: a limitation of the firmware, but perhaps in the hardware, as well.
It's the floppy port style 20 mb hard disk for pre SCSI Macs, and precious
few people care whether it works with Apple IIs.
Jeff Blakeney
On 7 Mar 1998 04:16:39 GMT, sh...@onyx.southwind.net (Randy
Shackelford) wrote:
>Jeff Blakeney (CUTj...@bconnex.net) wrote:
>
>: Are you sure about this? It seems to me that if the disk isn't
>: initialized as a ProDOS disk, erasing it should give you an error.
>: Especially if you try to erase a 720k MFM disk into an 800k GCR. It
>: just ain't gonna happen.
>
>Righto, that doesn't work.
I didn't think that would. I don't think we have a program that
supports erasing a disk into a 720k ProDOS disk, but that might work
if we did have one. Although, I'd much rather reformat them to use
800k anyways because 80k per disk makes a big difference.
>: I'm just curious as to whether you are indeed erasing an MS-DOS
>: formatted disk into a ProDOS disk because, as far as I know, it is
>: impossible.
>
>I wasn't aware that this would work until I tried it the other day. But it
>really does work for HD disks.
Well, that's cool. That sure makes it quicker to turn MS-DOS
preformatted disks into ProDOS disks.
David Empson
<mke...@spam.eecs.wsu.edu> wrote:
> In article <1d5kp6z.kj...@dempson.actrix.gen.nz>,
> dem...@actrix.gen.nz (David Empson) writes:
> > <pub...@library.ucla.edu> wrote:
> >
> >> Wrong, the UDC works with the Mac HD20. I've seen one attached
> >> to an Apple IIe. There are two models of UDC cards. One is the
> >> older full size controller. The second one is the newer, half
> >> size card. The IIe that was connected to the HD20 used the full
> >> sized version. I would think that the half sized card would
> >> retain the capability.
>
> So what exactly is the Mac HD20? Is this just an external SuperDrive?
No. The HD20 is an old 20 megabyte hard drive that Apple made for use
with the Mac 128, 512 and Plus. It connects to the floppy port on the
Mac, which means it is very slow (serial transfer instead of parallel).
With the introduction of the Mac Plus with its SCSI port, the HD20 was
replaced with the HD20SC (SCSI version). There is no problem using them
on an Apple II, but the original HD20 doesn't work except with a UDC
card.
> I have connected a SuperDrive to my CPS UDC (half-sized I'm guessing)
> but it only recognized the drive as an 800K which I believe to be
> a limitation of the firmware, but perhaps in the hardware, as well.
Definitely the firmware, and almost certainly the hardware as well (it
can't handle MFM-encoded data, I expect, not to mention double the data
rate for high density disks).
> > Can anyone else out there confirm that they have failed to get a UniDisk
> > 3.5 working on a UDC? If so, can you please let us know which UDC
> > version it was, and any other identifying characteristics.
>
> If I had a UniDisk 3.5, I'd test this out. Unfortunately, I don't think
> a Macintosh external is the same thing. In fact, I distinctly recall
> the the UniDisk 3.5 having a 6502 built into the drive case.
Correct. The UniDisk 3.5 is effectively an Apple 3.5 Drive with a
replacement controller board inside the drive that has its own 65C02,
RAM, ROM and IWM (disk controller). It uses an intelligent packet
protcol to communicate with the computer, and the transfer rate is about
half that of an Apple 3.5 Drive.
The Macintosh 800K external drive (without eject button) is the same
drive mechanism, but with no interface circuitry (the computer controls
the drive directly); there is a small amount of rearrangement going on
in the Apple 3.5 Drive which is required for Apple II support (and this
drive also supports the eject button).
David Empson
<mke...@spam.eecs.wsu.edu> wrote:
> In article <19980307074...@ladder03.news.aol.com>,
> super...@aol.com (Supertimer) writes:
> > CUTj...@bconnex.net (Jeff Blakeney) wrote:
> >
> >>On 4 Mar 1998 05:08:35 GMT, super...@aol.com (Supertimer) wrote:
> >>
> >>[snip]
> > You are right that you can't erase a 720K MFM disk into an 800K
> > GCR disk. You can, however, erase a 1.44MB MFM disk into a
> > 1.44MB MFM disk, which is what is happening with a ProDOS
> > erase of an MS-DOS disk.
>
> Now this must be some characteristic of the Apple IIgs operating
> system. If I attempt to erase (not format) an MS-DOS 1.44MB disk
> with Copy II+ it reports "not a ProDOS disk," and quits.
That would be a limitation of Copy II+, not the "IIgs operating system"
(which isn't even being used when Copy II+ goes to format a disk). It
checks the volume, doesn't recognise the file system (and possibly the
volume size), and refuses to do anything with it.
ProDOS-8 provides no support for formatting disks - it is up to the
application to implement this. It requires direct hardware access for
5.25" disks. For other devices, the application must use the ProDOS
block driver (provided by the card firmware, or inside ProDOS itself in
the case of /RAM).
This assumes you want to do an actual format operation. An "erase"
operation (writing boot blocks and an empty file system onto an already
formatted volume) can be done with ProDOS block-level calls, with some
assistance from the firmware driver to determine the size of the volume.
Even in this case, ProDOS-8 doesn't know what you are doing, and the
application must provide the code which goes in the boot blocks.
Under GS/OS, the operating system provides format and erase calls that
do all this, so it is not necessary for applications to provide special
code (except user interface support as required) if they want to format
or erase disks.
mke...@spam.eecs.wsu.edu
In article <1d691fc.vt...@dempson.actrix.gen.nz>,
dem...@actrix.gen.nz (David Empson) writes:
>> Now this must be some characteristic of the Apple IIgs operating
>> system. If I attempt to erase (not format) an MS-DOS 1.44MB disk
>> with Copy II+ it reports "not a ProDOS disk," and quits.
>
> That would be a limitation of Copy II+, not the "IIgs operating system"
I would like to point out that I didn't state there was a limitation
of the "IIgs operating system" but that the outstanding characteristic
of the IIgs operating system is that it doesn't bother checking what
data is currently on the disk and will still provide a quick format,
a.k.a. an erase. I don't have an Apple IIgs so I wouldn't have
assumed the IIgs operating system to be a limitation.
Copy II+ on the other hand will search the volume before attempting an
erase to make sure it's a ProDOS volume, perhaps because it does nothing
more than clear out the block-use tables.
If I copy over the first few blocks from any ProDOS volume onto the
disk to be erased, Copy II+ happily sees a ProDOS formatted volume
and will erase the disk into the size based on a query from ProDOS.
In short, if I copy the blocks from a 140K volume onto an MS-DOS
720K diskette, a subsequent disk erasure of the 720K disk will
yield a 720K ProDOS volume.
> (which isn't even being used when Copy II+ goes to format a disk). It
> checks the volume, doesn't recognise the file system (and possibly the
> volume size), and refuses to do anything with it.
Volume size isn't the issue, so I've discovered, but you are correct
in stating that it doesn't recognize the file system and quickly
cancels the erasure.