Looking for 8" floppies with CP/M 2.2 for Altair with Tarbell controller

[Equalizer700]

I'm resurrecting my 1975 hand-built Altair. I'm looking for 8" floppies with CP/M 2.2 for an Altair with Tarbell controller and DualStor disk drives. Any leads will be greatly appreciated.

I also would like some advice on resurrecting some cassette tapes with Basic and ASM on them...I have an 88-ACR and the tape drive, but the tapes are so old I'm afraid to load them unless I am sure what I'm doing. Is there any PC software that will find and/or restore any dropped bits?

Does anyone know the format of the DualStor disks? SS or DS? SD or DD? Hard or soft sectored?

Any help or advice is welcome!

John

[billdeg]

John can you post a detailed pic of your controller? Some of the key wire jumper locations?
thanks.
bill

[Chuck(G)]

I probably have the boot floppy that I used with my Altair with the original Tarbell controller and MITS SIO card. No guarantees, but if it's still readable, I could send you a BIOS listing to peruse. Drop me a PM if you're interested.

[Equalizer700]

Bill and Chuck,

Sorry to have dropped out of sight for a month or two. Had to spend some time in the hospital but now everything is ok.

Bill, I have put high resolution pics of the Tarbell controller at www.speedreferrals.com/pic1.jpg through pic 4.jpg. As you'll see there are lots of jumpers on the back side (as with lots of things of that era). It looks like the board might have been jumpered to be a Rev B, since there is a B scratched on the back side. If you would like a better pic of an area of the board I will be happy to get it for you. There are no jumpers on the component side, just a dip switch.

Chuck, I appreciate the offer of a BIOS listing, but I don't know how to get from that to a bootable floppy. Do you know anyone who has the facilities to copy a disk? I have read that there are ways to read and write 8" floppies using a PC floppy interface cable and an adapter of some sort. Do you know who the experts are on this subject?

I really appreciate your help!

John

[Terry Yager]

Happy to see ya back on your feet. Stay well.

--T

[billdeg]

Here is mine
http://www.vintagecomputer.net/tarbe...controller.jpg

[Chuck(G)]

Chuck, I appreciate the offer of a BIOS listing, but I don't know how to get from that to a bootable floppy. Do you know anyone who has the facilities to copy a disk? I have read that there are ways to read and write 8" floppies using a PC floppy interface cable and an adapter of some sort. Do you know who the experts are on this subject?

Yes, you can make an adapter (or just get one from DBit Probably not a bad thing to have around in any case...

But, the Tarbell (mine looks just like Bill's) controller uses a WD1771 single-density controller, so your PC has to be capable of supporting FM recording mode. Not all are.

Fortunately, there's an easy way to separate the wheat from the chaff. Attached is a DOS executable called TESTSD.EXE. It attempts to format and read track 74 on the first 1.44MB 3.5" drive on your PC. Just boot DOS (can even reside on the test diskette), run TESTSD and look at the output.

I can supply an image in many formats; Dave Dunfield has written Image Disk which is a good one, but I can also supply TeleDisk images or any other format you'd care for.

I also have the manual for the Tarbell controller, if it's not online. Configuring those jumpers for your drives can get to be a head-scratcher without a guide.

[Equalizer700]

Bill,
Chuck,

Wow, thanks for the info! I have looked on all sorts of other boards and haven't found anyone else who even knows what I was talking about.

Believe it or not, my current PC doesn't even have a floppy drive...just the cable. I ordered a drive from Newegg and will run the test Chuck sent when I get it. I also have some other, older PCs lying around...I'm sure one of them will work.

I'll start saving my allowance for a dbit adapter, too.

I'll let you know the results...

Thanks again!

John

[virtualaltair]

Hi John,

How is your Altair Tarbell project going? I'm resurrecting my Altair/Tarbell/Vector Graphic project and have some questions:

What model of Altair do you have and what boards are in it? I'm especially interested in how much RAM amd which IO board.

You mention DualStor disk drives. Are these Vector-Graphic disk drives? If so, are they the original Dual-Stor or the newer Dual-Stor?

The following page has Dual-Stor pictures for reference:

http://vector-graphic.info/vg_dual_stor.aspx


Tom
www.virtualaltair.com
www.vector-graphic.info

[chuckcmagee]

Hey hey hey. If and when I get my 8" drives working, that Dbit thing sounds like just the ticket. Guess I'll have to run around and test with your SD test deal too. I wasn't having much luck finding a CP/M that was preconfigured for the Tarbell. Looks like take a closer look at the drives is the first order of biz.