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Format compatibility between CP/M-86 and the CP/M-80s?

leeb

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I am working to revive an old V20 laptop to run CP/M 86 since it isnt much good for anything else...:rolleyes:

My question to those of you who have used it... Is the '86 format more like MSDOS... and is it likely to be easy(ier) to work with '80 disk formats?
 
I believe CP/M-86 uses its own disk format, but don't quote me on that.

p.s. With a NEC V20 CPU, you can also run CP/M-80, because the V20 includes Intel 8080 emulation.
 
Nope, there's no practical difference between CP/M-86 and CP/M-80 as far as disk formats go. Like CP/M 3/CP/M Plus, there are some additional dummy directory entries for date stamps, but those are ignored by CP/M 2.2 and earlier. Even CP/M 68K uses the same file system.

Now, Concurrent DOS is a different matter--it uses the MS-DOS FAT file system.
 
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I believe CP/M-86 uses its own disk format, but don't quote me on that.

p.s. With a NEC V20 CPU, you can also run CP/M-80, because the V20 includes Intel 8080 emulation.

I can just imagine attempting to build a BIOS for a Tandy 1510HD to run CP/M-80 :nervous: + :confused: + :-o

Edit: Do you know of anyone who has done such a thing? Access to source code would be... interesting, at least! :D

Nope, there's no practical difference between CP/M-86 and CP/M-80 as far as disk formats go. Like CP/M 3/CP/M Plus, there are some additional dummy directory entries for date stamps, but those are ignored by CP/M 2.2 and earlier. Even CP/M 68K uses the same file system.

Now, Concurrent DOS is a different matter--it uses the MS-DOS FAT file system.

Its a pity I dont have CPM+ running on the 4p... it would make the disks damn-near indistinguishable between the two!

Thanks to both of you! Once I complete surgery on the floppy drive... presuming it is successful, I can attempt the Frankensteination of the laptop!:p
 
You need to understand that CP/M floppies aren't like MS-DOS floppies--there is no "standard" format, save the 8" single-density single-sided 128-byte sector version.

At best guess, there are probably somewhere around 750 different CP/M disk formats out there and probably more. I've seen about 550 of them myself.
 
I believe CP/M-86 uses its own disk format, but don't quote me on that.

p.s. With a NEC V20 CPU, you can also run CP/M-80, because the V20 includes Intel 8080 emulation.

You need to understand that CP/M floppies aren't like MS-DOS floppies--there is no "standard" format, save the 8" single-density single-sided 128-byte sector version.

At best guess, there are probably somewhere around 750 different CP/M disk formats out there and probably more. I've seen about 550 of them myself.

Oh yes, Im PAINFULLY aware of that! I have also successfully 'modified' Montezuma's format(s) to properly read 'raw data' from a couple of sources. (USING that data however is yet to be...)

Just a bit of 'pipedreaming'! :D
 
Yes, Kaypro even had at least six [6] different CP/M versions alone ! What a mess !

So many today find that out when they get an inexpensive - FREE? - Kaypro, but with no disks.

Then if the Kaypros were "modified" in some way by some of their owners, then things can get really "dicey !"

You just have to check the chips, etc. “under the hood” to verify what you really have. Bitsavers free download Kaypro technical manuals can help.

Of course, Kaypro in the later years when they were struggling to just survive with the incredible onslaught of Compaq, many issues in manufacturing probably occurred to further complicate matters – just what was in some of those computers that they were manufacturing ?

If you were ever in “production,” you can appreciate what can [and often does] go
wrong ! I was and the stories to tell – mostly “funny” and preventable !

Guess that is why "deviceside" has not gotten into CP/M that much.

By the way, Adam of "deviceside" just emailed me that he is adding some drivers so files converted by Uniform, that came with Kaypros and some other computers, will work better with his device.

If you do not know, Uniform can convert CP/M files, along with many other formats from many other computers, to MS-DOS files. It will format a 5.25” floppy disk to MS-DOS and put these converted files on it. Uniform is on eBay many times for less than $5.

My wife and I are just thrilled, since we have thousands of such floppies with a lot of our research and other work on them from the 1980’s / 1990’s.

When I get these new drivers I will see and let you all know.

Right now, briefly, I have found "it works as advertised" – but as some have pointed out - make sure you understand exactly what you are getting.

Will do the requested review when all of this is finally resolved and verified.

Frank
 
Oh yes, Im PAINFULLY aware of that! I have also successfully 'modified' Montezuma's format(s) to properly read 'raw data' from a couple of sources. (USING that data however is yet to be...)

Just a bit of 'pipedreaming'! :D

If you have a PeeSee that will boot DOS, you might want to consider 22DIsk...
 
If you have a PeeSee that will boot DOS, you might want to consider 22DIsk...
Hey, I've chatted with the guy who wrote that; he's helped me out a few times and I think he even hangs out on this forum sometimes...
And I think he had something to do with the 22NICE emulator too...
 
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Yep. I've used 22DSK on a MS-DOS machines to stock up a Kaypro with software. The progam works well and seems to support many CP/M formats.

Tez
 
If you have a PeeSee that will boot DOS, you might want to consider 22DIsk...

Yep. I've used 22DSK on a MS-DOS machines to stock up a Kaypro with software. The progam works well and seems to support many CP/M formats.

Tez

Acually I DO have a copy of that... The issue of using it is discussed in the 'software project' thread I started... a bit too far back! :(

That is partly why the interest/attempt to play GOD with the laptop... so that I will no longer need to juggle DOS/XP...

The thinking follows thus: If CP/M-86 is a closer 'fit' to the ultimate plans... it might be worth a look... I have a good 4p emulator but I believe Ive seen some inconsistencies that need addressing... along with the fact that the emulator only knows about original-type RS hard drives/controllers and would require major programming to duplicate the GIDE interface I am using...

Unfortunately I found out that the FD in the laptop has/had a broken upper head... sheared right off the transport! And, of course, even if I could adequately align a replacement onto the transport, the connectors are different between the laptop drive (a matsushita) and the common PC-size drives... so that wouldnt work either. Adding insult to injury, the ribbon connector was also damaged, so micro-surgery to change the head assy would be useless too....

Wow! Rant over! :D
 
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Not familiar with a 4P and I'd be hesitant anyway to replace a head, but is it really a big problem to replace the drive with a "standard" PC type? What does the interface look like?
 
If you have a PeeSee that will boot DOS, you might want to consider 22DIsk...

Not familiar with a 4P and I'd be hesitant anyway to replace a head, but is it really a big problem to replace the drive with a "standard" PC type? What does the interface look like?

Im sorry... it is the 1500hd laptop that has the dead FD... not the 4p (which is sporting a 'standard' 3.5 now).
The laptop has the funky-thin Matsushita drive with the ribbon cable on it...
Unfortunately without a working FD, I cannot continue the resurrection of the laptop to realize the ultimate goals...
(insert evil laugh here)
:D
 
Will a Teac FD-05 work? I may have one of those kicking around.

BTW, if you re-post here with a question addressed to me and don't get an answer, please PM me. I'm not trying to ignore you, but sometimes a post will slip by the "New Posts" tool and I'll miss it.
 
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Will a Teac FD-05 work? I may have one of those kicking around.

BTW, if you re-post here with a question addressed to me and don't get an answer, please PM me. I'm not trying to ignore you, but sometimes a post will slip by the "New Posts" tool and I'll miss it.

Dunno... the original is a Matsushita EME-263MG... it has a 26-pin ribbon cable that is permanently attached to the board.... and I recently learned that it has a belt-drive for the spindle... and the belt is SERIOUSLY stretched! Certainly explains why the disk never seemed to spin...

I am in hopes that another EME-xxx drive will be the same mechanically which would allow me to swap the interface board without having to mess with the heads... unless of course, the belt is no good on THAT one either!!

Bummer.

I certainly would entertain the idea of an FD-05 if the interface is the same... but I dont know the pinout of the cable and previous experience has taught me that Murphy's Laws RULE in these cases. :)
 
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Well, the FD-05 takes a 26-pin flex cable connector (the flat mylar type that wedges the cable edge), has direct drive and acan also handle 1.44MB. The one I have is an FD-05HG and can also do 1.23MB PC98-style floppies. Here's a spec sheet.

These were used extensively in laptops--the one I have is black with a blue eject button and was from an IBM Thinkpad.
 
Well, the FD-05 takes a 26-pin flex cable connector (the flat mylar type that wedges the cable edge), has direct drive and acan also handle 1.44MB. The one I have is an FD-05HG and can also do 1.23MB PC98-style floppies. Here's a spec sheet.

These were used extensively in laptops--the one I have is black with a blue eject button and was from an IBM Thinkpad.

Thanks for the info- it has the pinout in it (if only for this drive)...

I have some 'test units' coming from ebay (real cheap), but if they dont work (or cant be used) I will PM you!
 
Update...

Update...

I now have a working FD in the 1500... An EME-273 (as opposed to the original 263)...

Tho there are differences, specifically that the eject button is on TOP instead of BOTTOM, it DOES work and seems to be very happy there! ;)

In fact, I have ordered a 2nd unit to keep as a backup...

Once I resolve the Hard drive issue (being it dont work! :mad:) I can work on deciding on CP/M-86 or M$DOS...

I am looking also for a memory stick (1Mb) for it, but it is a proprietary 35-pin SIMM (the same as the 2800 series if I recall, but the 2800 takes up to 4 of them) and the 30-pinners I ordered dont fit.

Big loss... the 4 of them only cost $1... and it cost them $1.39 to send them... Do I feel guilty! :mrgreen:

Next post when the/any HD is working! :D
 
The Zombie LIVES!!

The Zombie LIVES!!

I actually managed to get the original HD working... for the moment, at least!
I DO have a replacement on the way, but since this one is alive again, I will work with it until the inevitable happens! :lookroun:

I believe I have also found the pinout for the internal modem... which I will likely NEVER find! Unfortunately the connector (it appears) is a TTL-level RS232 connector. Which actually makes sense, as the setup program only changes it from COM:1 to COM:2 and back.
Perhaps I can get creative and build something that will fit that will be a bit more useful than a 2400-baud modem.

Well, that's what it could get... back in the day! Right now, a modem in general is not useful to me. RS232-to-USB, perhaps?:crazy:


Oh, happy day! :D
 
I believe I have also found the pinout for the internal modem... which I will likely NEVER find! Unfortunately the connector (it appears) is a TTL-level RS232 connector. Which actually makes sense, as the setup program only changes it from COM:1 to COM:2 and back.
Perhaps I can get creative and build something that will fit that will be a bit more useful than a 2400-baud modem.
You can add a level shifter for an extra serial port...something like the MAX232 from Maxim works fine and requires only a +5v supply (easily stolen elsewhere...it probably comes up the header anyway) and some external caps. Since it's RS-232 there are a number of interesting things you could attach, provided they'd fit in the space for the modem. You could probably chop up a faster internal modem from a different laptop, or an old PCMCIA modem, as long as the modem was a true serial modem and not a softmodem.
 
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