23 Mar
2007
23 Mar
'07
2:02 p.m.
I finally got an 8-inch floppy drive connected to a PC and now I want
to create an 8-inch boot floppy from a Teledisk image I found, but
tdcheck says it's an 82 track 3.5-inch floppy image. That's seems
odd.
http://www.retroarchive.org/cpm/os/ALTOS.ZIP
Anyone know for sure if I should be able to use Teledisk to write this
image directly to an 8-inch floppy? Or would I need to do something
like write the image to a 3.5 inch floppy and then use ImageDisk to
read that floppy and write it to the 8-inch floppy?
-Glen
23 Mar
23 Mar
4:19 p.m.
On 23 Mar 2007 at 11:02, Glen Slick wrote:
I finally got an 8-inch floppy drive connected to a PC
and now I want
to create an 8-inch boot floppy from a Teledisk image I found, but
tdcheck says it's an 82 track 3.5-inch floppy image. That's seems
odd.
http://www.retroarchive.org/cpm/os/ALTOS.ZIP
Anyone know for sure if I should be able to use Teledisk to write this
image directly to an 8-inch floppy? Or would I need to do something
like write the image to a 3.5 inch floppy and then use ImageDisk to
read that floppy and write it to the 8-inch floppy?
Go ahead and give it a shot. If there are too many tracks in the
image, the drive will simply bump up against the end stop. It's till
a 500Kbps data rate. I have no idea why someone called the original
drive what they did.
Take my word for it--honest.
Cheers,
Chuck
6:08 p.m.
When writing an image back to a drive, TeleDisk doesn't really care
about anything more than the density (low or high), recording mode
(FM/MFM), and number and size of sectors. Gap computation is
performed on the basis of the drive being used to write. So declare
your drive as either a 5.25" 1.2MB or an 8" to TeleDisk and you'll be
fine, assuming your controller will write FM. Either way, the track
computation will be based on 500K data rate and a 360 RPM drive.
As far as the 82 cylinders goes; it's the number used for the maximum
track inspected by TeleDisk--TD will keep looking up to track 82 (or
42 for a 48 tpi drive) or (79 for an 8" drive) until no data is
returned. Some drives will hit a mechanical stop at track 80 or so,
so the positioner will just bounce against it, returning the same
data. On playback, the same thing will happen, so you'll get a valid
recreation. Things had to be this way because some copy-protected
formats use up to 42/82 cylinders; and some customers wanted to
recover manufacturing information if present (which is typically
recorded on track 40 or 80).
Hope this clears things up.
Cheers,
Chuck
10:57 p.m.
Hi Chuck,
I know you don't want to do teledisk support, but having just spend
a bit of time trying your suggestion, I have one burning question...
When writing an image back to a drive, TeleDisk
doesn't really care
about anything more than the density (low or high), recording mode
(FM/MFM), and number and size of sectors. Gap computation is
performed on the basis of the drive being used to write. So declare
your drive as either a 5.25" 1.2MB or an 8" to TeleDisk and you'll be
fine, assuming your controller will write FM. Either way, the track
computation will be based on 500K data rate and a 360 RPM drive.
HOW exactly do you do this? - I admit I don't know teledisk very well,
and have never set up a custom drive table etc. however I tried to write
the image with a BIOS drive configured as a 1.2M HD - this should let
TeleDisk know it's 500kbps and 360rpm, however Teledisk refuses to try
and write it saying it's the "wrong drive type". I tried with TD2.11 and
TD2.15
As far as the 82 cylinders goes; it's the number
used for the maximum
track inspected by TeleDisk--TD will keep looking up to track 82 (or
42 for a 48 tpi drive) or (79 for an 8" drive) until no data is
returned. Some drives will hit a mechanical stop at track 80 or so,
so the positioner will just bounce against it, returning the same
data. On playback, the same thing will happen, so you'll get a valid
recreation. Things had to be this way because some copy-protected
formats use up to 42/82 cylinders; and some customers wanted to
recover manufacturing information if present (which is typically
recorded on track 40 or 80).
This gives us another clue - I was able to read the data from those
extra tracks, and 0-76 are what you would expect, 77-82 do contain
data, but are ALL exact duplicates of 76 - ie, the image WAS read on
an 8" drive (misconfigured as a 3.5"), and it "hit the stop" right
at track 77 - no extra tracks at all.
Btw - for those who want to make these disks... I was able to recreate
the disk on 8" by a round-about method. I got TeleDisk to write the
disk to a 3.5" HD drive, then used ImageDisk to read it into a .IMD
file which I could then write out to the 8" drive.
This worked, and I was able to look into the CPM 2.24 image and see
lots of strings referencing "ALTOS 64k loader" and such - so it is an
Altos disk. I was also able to read and examine the extra tracks as
noted above (IMDV is proving quite handy!)
After writing the disk with TD, TD2.11 could not read it (it locked
up requiring a hard-reset) - TD2.15 was able to re-read it. It could
also write it correctly, even though my earlier test showed that
TDCHECK from 2.15 gave bizarre side numbers. I think my final working
transfer was done with TD2.15.
The reason I did so much screwing around with TD and reading the disk
was that the first time I tried this I used the DIAG disk, and ended
up with a blank formatted disk - I was trying to verify that TD read
back the same as it wrote ... turns out that DIAG is in fact a blank
formatted disk... But at least one of the CP/M disks appear to contain
a valid boot disk image.
If anyone wants, I can use my setup to convert these to ImageDisk
format and post them to my site.
Regards,
Dave
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.classiccmp.org/dunfield/index.html
5:36 p.m.
Btw, if anyone still needs them, I have converted the ACS8000 disks
in question to .IMD format and posted them to my site.
The CP/M 2.21 and 2.24 disks are both single-density all the way
through and converted with no problems.
The CP/M 2.24A disk appears to be a double-density disk with single-
density boot tracks - There were two problems:
- Tracks 70-77 are missing sector 6 for some unknown reason...
However I checked with IMDV and the other sectors on these
tracks do not contain data - so it's not likely to be a
problem as a boot disk.
- Track 2 appears as a single 128 byte SD sector with sector
ID #100 - don't ask me why ... ImageDisk read it OK and
stored it as read. TeleDisk gets the same thing (single
128byte SD sector with id=100), but after that it gets
confused and thinks the disk is a 48tpi disk in a 96tpi
drive and double-steps the the rest of the disk, complaining
all the way that the cylinder IDs are wrong) --- so I
can't say if this image will actually work or not.
Dave
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.classiccmp.org/dunfield/index.html
23 Mar
23 Mar
4:37 p.m.
I finally got an 8-inch floppy drive connected to a PC
and now I want
to create an 8-inch boot floppy from a Teledisk image I found, but
tdcheck says it's an 82 track 3.5-inch floppy image. That's seems
odd.
http://www.retroarchive.org/cpm/os/ALTOS.ZIP
Anyone know for sure if I should be able to use Teledisk to write this
image directly to an 8-inch floppy? Or would I need to do something
like write the image to a 3.5 inch floppy and then use ImageDisk to
read that floppy and write it to the 8-inch floppy?
I took a look at the archive in question - here's what I could figure
out:
I first tried TDCHECK from TD2.15 - this reports that it's reading side
128 which seems really wrong. Noting that it also said the image was
made with TD2.1, I tried TD2.11 (closest I have) and it did report that
it was reading side 0 and side 1 ... so If you do try and recreate it,
I would suggest using TD2.1x
It also reports FM on a 3.5" drive with 26 sectors/track. 3.5" drives
normally operate at 300rpm. An 8" drive operates at 360 rpm, and
normally has 26 FM sectors on a track. If the image were truly on a
300 rpm drive, I would expect to see more sectors. So the sectors match
an 8" drive. Teledisk tries to describe it's disks in terms of PC drives,
and since a PC doesn't have a specification for an 8" drive, it would
have had to be manually set up - My guess is that whomever made those
images didn't have the drives set up correctly. TD probably thought it
was talking to a 300rpm drive, but the # sectors makes me thing it was
actually a 360 rpm drive.
Unfortunately it may not work backwards - TeleDisk has to calculate the
gaps based on total number of bits/track and I assume it will determine
this from what it thinks the drive RPM is... I might work ... doesn't
hurt to try. If it doesn't, you might be able to write it to a 3.5"
disk, read that into IMD and write it out to a 8".
Also concerneing is the fact that TDCHECK is reporting 82 tracks - does
the Altos have special drives with more tracks? - I've seen people try
to get an extra track or two, but 5 tracks past the end of the drive (8"
= 77 tracks) seems too much.
Dave
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.classiccmp.org/dunfield/index.html
5:09 p.m.
Glen Slick wrote:
I finally got an 8-inch floppy drive connected to a PC
and now I want
to create an 8-inch boot floppy from a Teledisk image I found, but
tdcheck says it's an 82 track 3.5-inch floppy image. That's seems
odd.
http://www.retroarchive.org/cpm/os/ALTOS.ZIP
Anyone know for sure if I should be able to use Teledisk to write this
image directly to an 8-inch floppy? Or would I need to do something
like write the image to a 3.5 inch floppy and then use ImageDisk to
read that floppy and write it to the 8-inch floppy?
It is possible that there were excess tracks when a 3 1/2 inch disk was
added to a system with 8" drives, especially at Altos. there may not be
any relevent data on those tracks, or if there is, you may be out of
luck unless you figure out how to get a system going with 3 1/2 inch
drives and gen an 8" disk off the Altos system.
Some systems never used the 3 1/2 inch drives as a main drive, but
rather as a convenience. the system never knew there was anything
other than 8" drives attached. I recently saw that with old Computer
Automation systems, for example.
jim
7:53 p.m.
on 3/23/07 1:02 PM, Glen Slick at glen.slick at gmail.com wrote:
I finally got an 8-inch floppy drive connected to a PC
and now I want
to create an 8-inch boot floppy from a Teledisk image I found, but
tdcheck says it's an 82 track 3.5-inch floppy image. That's seems
odd.
http://www.retroarchive.org/cpm/os/ALTOS.ZIP
Anyone know for sure if I should be able to use Teledisk to write this
image directly to an 8-inch floppy? Or would I need to do something
like write the image to a 3.5 inch floppy and then use ImageDisk to
read that floppy and write it to the 8-inch floppy?
-Glen
I ran into this file a few years back and wasn't able to do much with it. I
later created my own Altos floppy images using both Teledisk and Imagedisk.
I'll send them to you offlist for you to try out.
Richard Lynch
10:21 p.m.
On 3/23/07, Richard Lynch <richardlynch3 at tx.rr.com> wrote:
I ran into this file a few years back and wasn't able to do much with it. I
later created my own Altos floppy images using both Teledisk and Imagedisk.
I'll send them to you offlist for you to try out.
Richard Lynch
I have an ACS8000-7 dual floppy and an ASC8000-10 floppy / hard drive.
On both of them I get the monitor prompt to insert a floppy for
autoboot (the -10 fails the hard drive boot first). I tried creating
floppies from ACSBTMD1.IMD and DIAG26K.IMD and I don't get any
indication that anything is happening on either system with either
floppy. No additional output on the terminal and it doesn't appear
that the floppy is seeking at all.
I don't know for certain that the floppy drives are actually working
on either system other than the motors running. I got them as-is a
couple of years ago with no boot floppies and no way to create boot
floppies at the time.
I suppose I could pull the drives and attach them to the PC I used to
write the floppies and see if I can read the floppies back ok. That
sounds too much work like work instead of fun for this evening.
-Glen
11:39 p.m.
On 3/23/07, Glen Slick <glen.slick at gmail.com> wrote:
I have an ACS8000-7 dual floppy and an ASC8000-10 floppy / hard drive.
On both of them I get the monitor prompt to insert a floppy for
autoboot (the -10 fails the hard drive boot first). I tried creating
floppies from ACSBTMD1.IMD and DIAG26K.IMD and I don't get any
indication that anything is happening on either system with either
floppy. No additional output on the terminal and it doesn't appear
that the floppy is seeking at all.
Problem solved. I took a break and whlie out taking the dog for a
walk I started thinking about something I observed that puzzled me a
bit but dismissed at the time. I was creating the disk with a Tandon
TM848-2 and double sided disks and when I was looking at disk spinning
in the drive in the ASC8000 I thought it odd that the index hole
didn't appear to line up with the index sensor on the drive.
While out walking it occured to me that maybe a single sided floppy
has the index hole in different position. Just now I opened up a box
of single sided floppies that I was lucky to have on hand and took a
look a the index hole location and that answered my question. I just
now created a singled sided disk from the ACSBTMD1.IMD image from
Richard on the TM848-2 which I now see has two index sensors and it
booted up right away on the ASC8000 with the singled sided Shugart 80x
drive.
Learn something new every day. 8-inch floppies were just before my
time so I'm a little ignorant about their details.
-Glen
6307
days inactive
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10 comments
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participants (5)
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cclist＠sydex.com -
dave06a＠dunfield.com -
glen.slick＠gmail.com -
jwstephens＠msm.umr.edu -
richardlynch3＠tx.rr.com