John.R.Lyman@cdcnet.ahse.cdc.com (11/26/90)
] > The WD1771 FDC controller used in the Big Board is the same as used in
] > the Xerox 820 and is capable of using 5.25" floppies. What needs to be
] > done is to cut the data transfer rate from the 8" rate (500,000K bps) to
] > the 5.25" rate (250,000K bps) and, obviously, accommodate the 34 pin
] > connector on the 5.25" drive.
]
] Or, you can just grab some 1.2 MB drives from an IBoringM AT. They run at
] 500 KHz, so should work just fine.
I have a Big Board II, and was looking for some 1.2 Meg DSDD 8" floppy
drives. I found them to be very expensive compared to 1.2 Meg 5.25" drives.
So I went out and bought a PC compatible (i.e. standard) 1.2 Meg 5.25" drive
and hooked it up to the BB2. I now have a 1.2 meg floppy drive! I figure
that a 3.5" drive should also work, but I haven't tried one yet.
I had two problems, 1) the BIOS was assembled to support single sided
drives only, so I had to change a EQU and reassemble, 2) the 5.25" drives
don't usually provide a READY signal like the old 8" drives did, I just
hard wired this signal to ZERO (this causes a retry during formatting
when you switch sides, and may cause some when the motor has to start up,
but, I haven't noticed any problems. The 5.25" drive is faster than the
old SSDD 8" drives, and a lot quieter (the motor shuts off too)!
John Lymanfzsitvay@techbook.com (Frank Zsitvay) (12/02/90)
In article <901126112316052-MTAVN3*John.R.Lyman@cdcnet.ahse.cdc.com> John.R.Lyman@cdcnet.ahse.cdc.com writes: > > I have a Big Board II, and was looking for some 1.2 Meg DSDD 8" floppy >drives. I found them to be very expensive compared to 1.2 Meg 5.25" drives. Hmm - I don't know where you were looking for 8 inch drives, but i have found that usually they can be had very cheaply. the key is not to buy them mail order, as most mail order houses charge too much and they are expensive to ship compared to 5.25 inch drives. however, there are advantages to the 5.25 inch hd drives, namely the ease of obtaining media. for 8 inch systems, you sometimes have to get quite creative to find the disks, but usually when you do they are very cheap. (exception - radio shack) >So I went out and bought a PC compatible (i.e. standard) 1.2 Meg 5.25" drive >and hooked it up to the BB2. I now have a 1.2 meg floppy drive! I figure >that a 3.5" drive should also work, but I haven't tried one yet. they do work, and there is an added bonus. if you modify your bios to use all 80 tracks on each side, you'll get more data on them than an ibm can. > I had two problems, 1) the BIOS was assembled to support single sided >drives only, so I had to change a EQU and reassemble, 2) the 5.25" drives >don't usually provide a READY signal like the old 8" drives did, I just >hard wired this signal to ZERO (this causes a retry during formatting >when you switch sides, and may cause some when the motor has to start up, >but, I haven't noticed any problems. The 5.25" drive is faster than the >old SSDD 8" drives, and a lot quieter (the motor shuts off too)! that i don't agree with. the tandon 848-2 drives in my trs6000 are very close to being a triffle faster than the teac hd drive in my at. it's virtually dead even. the tandon runs with a 3ms step rate. incidentally, the tandon drives put 1.2 megs on a disk, and can be had for $30 here in portland. they are perhaps the best half-height double sided 8 inch floppies ever made. by the by, i have a question regarding 8 inch floppies on ibm clones. uniform is very handy in formatting oddball disk formats, but i was wondering if it is possible to use an 8 inch drive on an AT floppy controller to format and read 8 inch formats?? -- fzsitvay@techbook.COM - but don't quote me on that.... American Oil Company motto - Bend over, We'll pump!!!
rzh@ICF.LLNL.GOV (R. Hanscom) (12/04/90)
In <1990Dec2.045012.25373@techbook.com> fzsitvay@techbook.com (Frank Zsitvay) writes: > by the by, i have a question regarding 8 inch floppies on ibm >clones. uniform is very handy in formatting oddball disk formats, >but i was wondering if it is possible to use an 8 inch drive on an >AT floppy controller to format and read 8 inch formats?? Check out Emerald in Oregon. They carry the "Compaticard" which is a PC compatible disk controller. I don't have one, but they appear to handle 8" drives on a PC, although I believe the ads say that the AT will not boot from an 8" drive (that may not be a big deal!). They are not cheap, but seem to answer your needs. [Emerald advertises in a number of publications. I've seen their ads in Circuit Cellar Ink] roger rzh@phoenix.ocf.llnl.gov icf!rzh@lll-winken.llnl.gov
donm@pnet07.cts.com (Don Maslin) (12/04/90)
fzsitvay@techbook.com (Frank Zsitvay) writes: > > by the by, i have a question regarding 8 inch floppies on ibm >clones. uniform is very handy in formatting oddball disk formats, >but i was wondering if it is possible to use an 8 inch drive on an >AT floppy controller to format and read 8 inch formats?? > It certainly should be. I am running an 8" drive on CompatiCard as a secondary FDC on my AT clone. The CC can also be used as a primary controller on an AT, as it supports 1.2 and 1.44 meg drives. Its major advantage to me is that it is a 4 drive controller. - don Keeper of the CP/M System Disk | UUCP: {nosc ucsd crash ncr-sd}!pnet07!donm Archives for the Dino(saur)SIG | ARPA: simasd!pnet07!donm@nosc.mil - San Diego Computer Society - | INET: donm@pnet07.cts.com
fzsitvay@techbook.com (Frank Zsitvay) (12/05/90)
In article <1990Dec3.224503.5999@simasd.uucp> donm@pnet07.cts.com (Don Maslin) writes: >fzsitvay@techbook.com (Frank Zsitvay) writes: >> >> by the by, i have a question regarding 8 inch floppies on ibm >>clones. uniform is very handy in formatting oddball disk formats, >>but i was wondering if it is possible to use an 8 inch drive on an >>AT floppy controller to format and read 8 inch formats?? >> >It certainly should be. I am running an 8" drive on CompatiCard as a >secondary FDC on my AT clone. The CC can also be used as a primary >controller on an AT, as it supports 1.2 and 1.44 meg drives. Its major >advantage to me is that it is a 4 drive controller. well, what i meant was could i connect my 8 inch drives to an existing AT HD controller and get the thing to work with uniform?? the reason why is because compaticards aren't exactly cheap, and i'd like to avoid that step if possible. i can make a proper cable, but i need to know if uniform understands such a setup. -- fzsitvay@techbook.COM - but don't quote me on that.... American Oil Company motto - Bend over, We'll pump!!!
donm@pnet07.cts.com (Don Maslin) (12/06/90)
fzsitvay@techbook.com (Frank Zsitvay) writes: > > well, what i meant was could i connect my 8 inch drives to an existing >AT HD controller and get the thing to work with uniform?? the reason >why is because compaticards aren't exactly cheap, and i'd like to >avoid that step if possible. i can make a proper cable, but i need to >know if uniform understands such a setup. > What I meant to imply is that the CompatiCard is essentially a 4-drive AT FDC. Therefore, it should be possible to connect to a regular AT FDC. Try it, all it should cost you would be the effort to make the cable. As to UniForm understanding it as an 8", I doubt it. But it should write to it in 1.2 format. Look into the capabilities of Driver.sys, though. - don > >-- Keeper of the CP/M System Disk | UUCP: {nosc ucsd crash ncr-sd}!pnet07!donm Archives for the Dino(saur)SIG | ARPA: simasd!pnet07!donm@nosc.mil - San Diego Computer Society - | INET: donm@pnet07.cts.com
ianj@ijpc.UUCP (Ian Justman) (12/07/90)
fzsitvay@techbook.com (Frank Zsitvay) writes: > well, what i meant was could i connect my 8 inch drives to an existing > AT HD controller and get the thing to work with uniform?? the reason > why is because compaticards aren't exactly cheap, and i'd like to > avoid that step if possible. i can make a proper cable, but i need to > know if uniform understands such a setup. I've been wondering that myself, but I have an XT and I have an SA851 busy doing nothing at the moment... However, if that bit fails, you might try 22DISK. It has some text in there about using 8" drives, and you can specify whether or not you're using a CompatiCard to drive it.
fzsitvay@techbook.com (Frank Zsitvay) (12/07/90)
In article <9012031701.AA16292@icf.llnl.gov.llnl.gov> rzh@ICF.LLNL.GOV (R. Hanscom) writes: >In <1990Dec2.045012.25373@techbook.com> fzsitvay@techbook.com (Frank Zsitvay) >writes: > >> by the by, i have a question regarding 8 inch floppies on ibm >>clones. uniform is very handy in formatting oddball disk formats, >>but i was wondering if it is possible to use an 8 inch drive on an >>AT floppy controller to format and read 8 inch formats?? > >Check out Emerald in Oregon. They carry the "Compaticard" which is a PC >compatible disk controller. I don't have one, but they appear to handle >8" drives on a PC, although I believe the ads say that the AT will not >boot from an 8" drive (that may not be a big deal!). They are not cheap, >but seem to answer your needs. perhaps i didn't make myself clear. (entirely possible, since i'm human and not perfect...) it's the fact that the compaticard is not cheap that causes me to post the question in the first place. now, i know the hardware of an AT floppy controller will be able to control an 8 inch drive. that is understood without question, since it is basically the same as the interface used with 8 inch drives. what i meant to ask was, "Does uniform know how to use the AT floppy controller when it is connected to an 8 inch drive??" i have a space in my system's floppy storage system that is designed for AT compatible HD disk drives, but what i want to know is if i were to connect an 8 inch drive to it (with, of course, a cable that routes all of the signals where they should go) can i expect uniform to be able to work with this setup? currently, i have a western digital WD1003-WA2 controller with both a st225 and a teac HD drive connected to it. there is room to connect another floppy drive to the controller (it supports 2 drives), and i'd like to put my 8 inch drive on that. i know a compaticard would solve the problem, but in my situation that is not an alternative. -- fzsitvay@techbook.COM - but don't quote me on that.... American Oil Company motto - Bend over, We'll pump!!!
donm@pnet07.cts.com (Don Maslin) (12/09/90)
fzsitvay@techbook.com (Frank Zsitvay) writes: > > now, i know the hardware of an AT floppy controller will be able to control >an 8 inch drive. that is understood without question, since it is basically >the same as the interface used with 8 inch drives. > > what i meant to ask was, "Does uniform know how to use the AT floppy >controller when it is connected to an 8 inch drive??" > It is necessary for UniForm to be 'advised' of the presence of a particular drive in order for it to access it. This is done in the AT's CMOS and/or in the config.sys file - depending on the controller, etc. In the case of CompatiCard, there is the statement: device = ccdriver (followed by appropriate hyroglyphics) that identifies the drive parameters. It may well be possible to accomplish the same thing using whatever driver your HDC/FDC uses to identify attached floppies. But, not having tried it, I don't know for sure. Hopefully some other reader does, and will share his wisdom with us. > > i know a compaticard would solve the problem, but in my situation that >is not an alternative. > That is understood and appreciated. - don Keeper of the CP/M System Disk | UUCP: {nosc ucsd crash ncr-sd}!pnet07!donm Archives for the Dino(saur)SIG | ARPA: simasd!pnet07!donm@nosc.mil - San Diego Computer Society - | INET: donm@pnet07.cts.com