sparks@batcomputer.tn.cornell.edu (Steve Gaarder) (09/01/87)
I'm looking for a way to connect a Shugart SA810 half-height single-side
8 inch floppy to an HP Vectra (AT compatible) for the purpose of reading
standard CP/M disks. Two questions:
1) Hardware: Since the high-density drive uses the same data rate as an
8 inch drive, can I hook up the drive to the existing controller? I
know the bios won't be able to deal with it, but that's a software
problem. If the standard controller won't work, who makes a board that
will?
2) Software: Does anyone know of software that will read CP/M 8 inch
disks, using whatever controller is required?
--
Steve Gaarder
Cornell University, 171 Hollister, Ithaca NY 14853 607-255-5389
UUCP: {cmcl2,decvax,rochester,uw-beaver,ihnp4}!cornell!batcomputer!sparks
BITNET: sparks@crnlthry.BITNET ARPA: sparks@tcgould.tn.cornell.eduboykin@custom.UUCP (09/02/87)
In article <2211@batcomputer.tn.cornell.edu>, sparks@batcomputer.tn.cornell.edu (Steve Gaarder) writes: > I'm looking for a way to connect a Shugart SA810 half-height single-side > 8 inch floppy to an HP Vectra (AT compatible) for the purpose of reading > standard CP/M disks. Two questions: > > 1) Hardware: Since the high-density drive uses the same data rate as an > 8 inch drive, can I hook up the drive to the existing controller? Data rate has little to do with the problem. As a simplistic answer, the two cables are different (8" drives have a 50 pin connector, 5 1/4's have a 34 pin connector. Although I haven't ever looked into this, I doubt very strongly if there is any way to simply reroute signals so the two would be compatible. The real answer is that the two drives are not compatible with each other. In the early PC days, when people were using 1.2MB 8" drives instead of the "new and improved" 160/320KB 5 1/4" drives from IBM, there were a few companies who produced an 8" controller for the PC. The only one I remember is Maynard electronics. I recently looked at one of their ads for a friend wishing to do the same thing as yourself and did not see their 8" controller/drive in the ad anymore (no big surprise). I called them, they still make a board (2-3 week lead time) to control 4 floppies, including 8". They provide no driver software for it, you can't have another controller in your system i.e. the combined hard/floppy controller, unless you can disable the floppy portion. I asked them for some information, but I have not yet received it. > 2) Software: Does anyone know of software that will read CP/M 8 inch > disks, using whatever controller is required? In the early days of MS-DOS (actually, 86-DOS), there was a small program called RDCPM which allowed you to read CP/M diskettes. Of course, this doesn't solve the problem of needing drivers to talk to the board in the first place. Joe Boykin Custom Software Systems ...necntc!custom!boykin
ittfb@dcatla.UUCP (Thomas F. Blakely) (09/03/87)
In article <777@custom.UUCP> boykin@custom.UUCP (Joseph Boykin) writes: >In article <2211@batcomputer.tn.cornell.edu>, sparks@batcomputer.tn.cornell.edu (Steve Gaarder) writes: >> I'm looking for a way to connect a Shugart SA810 half-height single-side >> 8 inch floppy to an HP Vectra (AT compatible) for the purpose of reading >were a few companies who produced an 8" controller for the PC. The >only one I remember is Maynard electronics. I recently looked at I have one of these, as well as the Tall Trees device driver software if anyone is interested. I also have several 8" drives, both single and double sided. This stuff is "as-is" as I haven't used it in years and have no interest in testing it. Price: cheap (make offer). Tom Blakely (404)442-4866 {gatech, sun!sunatl}!dcatla!ittfb
toma@tekgvs.TEK.COM (Tom Almy) (09/03/87)
r In article <777@custom.UUCP> boykin@custom.UUCP (Joseph Boykin) writes: <In article <2211@batcomputer.tn.cornell.edu>, < sparks@batcomputer.tn.cornell.edu (Steve Gaarder) writes: << I'm looking for a way to connect a Shugart SA810 half-height single-side << 8 inch floppy to an HP Vectra (AT compatible) for the purpose of reading << standard CP/M disks. Two questions: << << 1) Hardware: Since the high-density drive uses the same data rate as an << 8 inch drive, can I hook up the drive to the existing controller? [No, needs new controller...] <The only one I remember is Maynard electronics. I recently looked at <one of their ads for a friend wishing to do the same thing as yourself <and did not see their 8" controller/drive in the ad anymore (no <big surprise). I called them, they still make a board (2-3 week lead <time) to control 4 floppies, including 8". [...] << 2) Software: Does anyone know of software that will read CP/M 8 inch << disks, using whatever controller is required? < I just looked in my documentation for Uniform -PC (from Micro Solutions) and it says that it will read from 8" using the Maynard controller on a PC or XT (but not AT compatible). What I don't understand is why the standard AT floppy controller won't work with 8" drives since the AT 5.25" format has the same data rates as an 8" DSDD drive. Even though the connector size is different, the pinouts are almost identical -- you can use ribbon cable with just a few "grafts". Tom Almy Tektronix, Inc toma@tekgvs.TEK.COM (former user of 8" DSDD CP/M system that blew the socks off the original IBM/PC)
paula@bcsaic.UUCP (Paul Allen) (09/05/87)
In article <777@custom.UUCP>, boykin@custom.UUCP (Joseph Boykin) writes: >In article <2211@batcomputer.tn.cornell.edu>, sparks@batcomputer.tn.cornell.edu (Steve Gaarder) writes: >> I'm looking for a way to connect a Shugart SA810 half-height single-side >> 8 inch floppy to an HP Vectra (AT compatible) for the purpose of reading >> standard CP/M disks. Two questions: >> >> 1) Hardware: Since the high-density drive uses the same data rate as an >> 8 inch drive, can I hook up the drive to the existing controller? > >Data rate has little to do with the problem. As a simplistic answer, >the two cables are different (8" drives have a 50 pin connector, 5 1/4's >have a 34 pin connector. Although I haven't ever looked into >this, I doubt very strongly if there is any way to simply reroute >signals so the two would be compatible. The real answer is that >the two drives are not compatible with each other. [stuff about PC 8" controllers and CPM deleted] Actually, it should be very simple to do this, provided that you don't mind building an adapter to match signals between the 34- and 50-conductor cables. All of the signals that matter are identical on 8" DSDD and 5.25" DSHD AT-style drives. The floppy controller in my Z100 can handle both 5" 360K and 8" 1.2M drives. I am planning to add a 1.2M 5" drive to use for backing up my hard disk sometime soon. I have been told that this has been done by other Z100 users. You will need good technical documentation on both the 8" and 5" 1.2M drive interfaces. The IBM AT Technical Reference might do for the 5" drive, but it fails to document the signal that switches the drive to high density mode. I have had conflicting information about this signal from several sources, and don't want to pass along misinformation. Possibly the tech ref for one of the AT clones would be a better source? Once you get the drive hooked up, you should be able to format it as if it was a 5" DSHD drive. Getting it to talk to CP/M diskettes may be tricky, since the diskettes will lack a proper media descriptor byte and the BIOS will not be able to tell what kind of floppy it is. Not having tried this myself, I think I'll keep my mouth shut about how hard I think your task will be. (My machine doesn't have a BIOS like the PC does. Maybe some PC hackers out there would care to comment?) Good luck! Paul Allen paula@boeing.com ...!uw-beaver!ssc-vax!bcsaic!paula
burton@parcvax.UUCP (09/06/87)
In article <2081@bcsaic.UUCP> paula@bcsaic.UUCP (Paul Allen) writes: > > >In article <777@custom.UUCP>, boykin@custom.UUCP (Joseph Boykin) writes: >>In article <2211@batcomputer.tn.cornell.edu>, sparks@batcomputer.tn.cornell.edu (Steve Gaarder) writes: >>> I'm looking for a way to connect a Shugart SA810 half-height single-side >>> 8 inch floppy to an HP Vectra (AT compatible) for the purpose of reading >>> standard CP/M disks. Two questions: >>> >>> 1) Hardware: Since the high-density drive uses the same data rate as an >>> 8 inch drive, can I hook up the drive to the existing controller? >> >>Data rate has little to do with the problem. As a simplistic answer, >>the two cables are different (8" drives have a 50 pin connector, 5 1/4's >>have a 34 pin connector. Although I haven't ever looked into >>this, I doubt very strongly if there is any way to simply reroute >>signals so the two would be compatible. The real answer is that >>the two drives are not compatible with each other. > >[stuff about PC 8" controllers and CPM deleted] > >Once you get the drive hooked up, you should be able to format it as if >it was a 5" DSHD drive. Getting it to talk to CP/M diskettes may be Even if all of the above is correct, there is still one difference between the 8" (double-sided, double density) and the AT high density drive: There are still some differences betweeen 8" and 5 1/4" high density drives. First, the 8" drive has only 77 tracks, and the AT's high density drive has 80 tracks. Second, there was absolutely no standardization in the CP/M world for double- density disks, either SS or DS. (In fact, that was almost a feature -) ) So, to read CP/M disks, you will need to program in various CP/M BIOS para- meters, including the sector size, interleave factor, directory size, etc. All in all, a real pain. Better to pay the man the money, if he will give you a solution that works. And, good luck. Oh, I almost forgot. Some CP/M disks were "hard-sectored". This used an "index hole" for each sector, instead of creating sectors by formatting the disk. I doubt that the PC's or AT's controller could handle those. As I said, good luck. -- Philip Burton burton@parcvax.COM ...!hplabs!parcvax!burton Xerox Corp. preferred path: burton.osbunorth@xerox.COM 408 737 4635 ... usual disclaimers apply ...
pozar@hoptoad.uucp (Tim Pozar) (09/09/87)
In article <777@custom.UUCP> boykin@custom.UUCP (Joseph Boykin) writes: > >In the early PC days, when people were using 1.2MB 8" drives instead >of the "new and improved" 160/320KB 5 1/4" drives from IBM, there >were a few companies who produced an 8" controller for the PC. The >only one I remember is Maynard electronics. I recently looked at >one of their ads for a friend wishing to do the same thing as yourself >and did not see their 8" controller/drive in the ad anymore (no >big surprise). I called them, they still make a board (2-3 week lead >time) to control 4 floppies, including 8". They provide no driver >software for it, you can't have another controller in your system >i.e. the combined hard/floppy controller, unless you can disable the >floppy portion. I asked them for some information, but I have not >yet received it. > Doesn't MS-DOS support 8 inch formats? I have a Microsoft 2.0 MS-DOS Programmers manual and they spec several 8 inch formats as being standard. Do you really need to create a driver for 8 inch? -- Tim Pozar UUCP pozar@hoptoad.UUCP Fido 1:125/406 USNail KKSF 77 Maiden Lane San Francisco CA 94108 PaBell (415) 788-3904
martyl@rocksvax.UUCP (Marty Leisner) (09/10/87)
In article <2899@hoptoad.uucp> pozar@hoptoad.UUCP (Tim Pozar) writes: >In article <777@custom.UUCP> boykin@custom.UUCP (Joseph Boykin) writes: >> > Doesn't MS-DOS support 8 inch formats? I have a Microsoft >2.0 MS-DOS Programmers manual and they spec several 8 inch >formats as being standard. Do you really need to create a >driver for 8 inch? > >-- The Xerox 16/8 used 8" floppy disks. However, it doesn't support the PC rom bios calls (???), so you need a customized driver which knows about your hardware. I use a SCSI host adapter board to connect to a DTC-1403D with 8" floppy and hard disks on it. I patched together a simple program which can read CP/M disks given important information found in the CP/M Bios. I've toyed with the idea of writing drivers for Ms/dos for the floppy and hard disk, but never found a need.
davidsen@steinmetz.steinmetz.UUCP (William E. Davidsen Jr) (09/10/87)
In article <2899@hoptoad.uucp> pozar@hoptoad.UUCP (Tim Pozar) writes: | Doesn't MS-DOS support 8 inch formats? I have a Microsoft |2.0 MS-DOS Programmers manual and they spec several 8 inch |formats as being standard. Do you really need to create a |driver for 8 inch? There are formats defined, and some systems support 8" disks. I use PC-PRO (PCDOS for CompuPRO computers). I'm pretty happy with the setup. I have upgraded my old "War Games" S100 to Z80, 8088, 80286, and there is now an 80386 board available, although after the first 4MB of memory you have to use the 16 bit bus. I agree that the signals on an AT controller should run an 8" drive. The device driver for "driver.sys" should be able to be configured to handle the format physically, but I don't know if the logical format tables for PC-DOS include the 8" versions. -- bill davidsen (wedu@ge-crd.arpa) {uunet | philabs | seismo}!steinmetz!crdos1!davidsen "Stupidity, like virtue, is its own reward" -me