PDA

View Full Version : ISO: 96tpi boot disk for Zorba



Chuck(G)
April 15th, 2009, 09:45 PM
A customer has a Zorba with Canon MDD210 floppy drives, which I assume are 96tpi, not the usual 48tpi. There are 48tpi Zorba boot images wandering around, but I've yet to find a 96tpi one. Anyone have such a beast? I do have a 96tpi Zorba data disk, but not a bootable one.

PM me if you can help.

Chuckster_in_Jax
April 16th, 2009, 09:27 AM
Have you tried making disks with the 48 TPI images on a standard 360K drive? They may work.
I have a Zorba 2000 with Mitsubishi 4853 drives.Same 720K 96TPI capacity. Unfortunately the power supply went out in it about 30 minutes after I powered it up. Mine did not come with any diskettes at all so I can't help you there. I remember SharkonWheels had a Zorba for sale not too long ago. Maybe he still has some diskettes or even still has the computer.

Have you looked at this website. It has the most resources for the Zorba computers I have found.

http://www.zorba.z80.de/history.html

Chuck(G)
April 16th, 2009, 10:54 AM
Putting the 48 tpi image on the first half of a 96 tpi drive will be the last resort. The Zorba site doesn't have anything but 48 tpi images on it.

I could conceivably generate a 96 tpi system image as I have access to the BIOS code, but I'm not inclined to do that without a Zorba to test it out on. I do have a 96 tpi Zorba data disk in my library, so I know the format.

There's also a Zorba tech ref on the web in form of a PDF.

Terry Yager
April 16th, 2009, 12:05 PM
I don't get it. Are you saying that the Zorba won't boot to a 48-tpi disk? My PMI will boot to either, if a 96-tpi is provided for the boot drive. After booting up, the 'COPY' program allows the choice of formats to use. OTOH, why don't you use Imagedisk, Uniform, 22Disk, etc to create a 96-tpi from the 48-tpi image?

--T

Chuck(G)
April 16th, 2009, 02:05 PM
I don't get it. Are you saying that the Zorba won't boot to a 48-tpi disk? My PMI will boot to either, if a 96-tpi is provided for the boot drive. After booting up, the 'COPY' program allows the choice of formats to use. OTOH, why don't you use Imagedisk, Uniform, 22Disk, etc to create a 96-tpi from the 48-tpi image?

That's what the customer is reporting. It could also be a mess of other things, including bad drives. Right now, I'm trying to deal with "you sent me bad disks; I'm sure that's what it is even though I've never booted this machine nor do I have any other disks for it." story.

Such is the joy of "the machine is over there, but I'm here" support.

22Disk? What's that?

The system appears to be the 7" model with the 96 tpi drives installed. Does anyone have any solid information on this?

The only other Zorba I had to get going had wildly out of alignment drives...

Yes, my next step (as I mentioned) will be to create a 96 tpi boot disk to see if that works. Just more postage and another package.

Chuckster_in_Jax
April 16th, 2009, 04:54 PM
22Disk? What's that?



When I was first getting started using CP/M on vintage computers I found that there was no " standard" format for writing CP/M files to a floppy disk. Most system manufacturers had a proprietary format for writing to floppies. It's not like M$-D0S where you can format a diskette and use the sys command to make a bootable disk that will boot-up most 8088 machines.
22Disk is a utility that will format diskettes in a number of various CP/M formats. It has disk definitions for a number of vintage computer systems. When setting up 22Disk you select from a list what format you want to use. One of it's best features is the ability to format a diskette in a CP/M machine's proprietary disk structure and copy files to it. I recently contacted them regarding a Televideo TS802 machine I was trying to generate a boot disk for. I found a zip file on the Web with individual files(not an image). I am inserting the correspondence I sent and their reply:

My correspondence:

I would like to order a current copy of 22DISK. I understand that the registered copy of 22DISK comes with 420 disk definitions.
I am trying to generate boot diskettes for a Televideo TS802 without any
success. I am using a Zenith Z386/25 computer with an Adaptec 1522A
controller which should do the job. I have tried the shareware version
of 22DISK and Teledisk but the computer won't boot with the floppies I
make. The TS802 floppy controller appears to be working OK and the
floppy drives works fine when connected to a PC. When the TS802 is
turned on, it sees the floppy drive, passes the startup tests and
resets the heads to track 00. The floppy LED stays on but the heads
don't step through the tracks and there is no error generated by the
system.
Anyway I want to eliminate the possibility that I have an invalid boot
disk. I understand that there were numerous formats for different CP/M
machines and 22DISK is the best utility for creating CP/M diskettes.

Please let me know how to order the software and how you would like
payment to be made.

Their reply:

Thank you for making sure we knew that you need to generate a boot
diskette for a Televideo TS802. You do need to have a valid boot
diskette to start with. 22DISK will allow you to copy boot tracks,
but it cannot generate a system diskette.

This limitation applies to other CP/M diskette formats supported by
our utility. Given appropriate hardware, you can format DATA
diskettes. SYSTEM diskettes are another matter.

You might contact the classic computer list for help in obtaining the
appropriate boot diskette.

Should you decide to purchase 22DISK for conversion tasks, we still
offer this product - but not as shareware. Our current price is $100,
but we can offer a 50% discount for non-business use.

Please let us know if you have questions or need other details about
what 22DISK can and cannot accomplish. We appreciate your interest in
our special products.


To understand all of the features of this utility, there are shareware versions on the Web that contain the Setup and User's guide.

Chuck(G)
April 16th, 2009, 05:07 PM
I know--I wrote that reply. :)

Chuckster_in_Jax
April 16th, 2009, 06:45 PM
I know--I wrote that reply. :)

Wow. From Sydex. Your someone that is really in the know about CP/M then.

Chuck(G)
April 16th, 2009, 07:20 PM
Wow. From Sydex. Your someone that is really in the know about CP/M then.

Yeah, but that doesn't help me with my Zorba problem. I'm going through the BIOS and boot source code now. Terry's right--the drives can be double-stepped by the system, but I'm still not sure how the system figures out if it's got 96 or 48 tpi drives installed.

I'll probably know by bedtime, though. ;)

cosam
April 17th, 2009, 12:45 AM
Not that it'll help by any means: I once picked up a bunch of DEC gear from a guy over here who had some stories to tell about the old machines he'd worked on. Back in the day, he and his colleagues referred to their Zorba by the backronym "Zeer Onbetrouwbaar Binair Reken Apparaat" or, roughly translated, "Very Unreliable Binary Calculating Machine". Hopefully that doesn't ring entirely true in this case! ;-)

Chuck(G)
April 17th, 2009, 09:34 AM
Part of the Zorba's problems in my limited experience was the unfortunate choice of Canon floppy drives. That the tech manual dedicates several pages to drive alignment and the Zorba floppies that I have in my library with bad alignment points to a prime source of failure.