a72@mindlink.UUCP (Raman Anand) (09/02/90)
Has anyone tried using Generic 1.44K internal IBM drives with Applied Engineering (AE) high density drivers? Raman ******************************************************************** * "I believe in a God which doesn't need heavy financing.", Fletch * * Raman Anand * * CIS: 73767,2161 VANCOUVER * * USENET: a72@mindlink.uucp BEAUTIFUL BRITISH COLUMBIA * * (604) 591-3664 (Home) - (604) 522-1137 (Work) * ********************************************************************
sparks@corpane.UUCP (John Sparks) (09/05/90)
a72@mindlink.UUCP (Raman Anand) writes: >Has anyone tried using Generic 1.44K internal IBM drives with Applied >Engineering (AE) high density drivers? >Raman How does the AE drives work anyway? I remember people asking Dave Haynie if the new version (then called 1.4) of AmigaDOS would support 1.44 meg floppies and the answer was no, because the chip that handles floppy access could not support any larger drives. It was a hardware limitation. So, how is AE getting amigaDOS to support high density drives? And can CBM maybe license this technology from them and make it an Amiga standard? -- John Sparks |D.I.S.K. Public Access Unix System| Multi-User Games, Email sparks@corpane.UUCP |PH: (502) 968-DISK 24Hrs/2400BPS | Usenet, Chatting, =-=-=-=-=-=-=-=-=-=-|7 line Multi-User system. | Downloads & more. A door is what a dog is perpetually on the wrong side of----Ogden Nash
hill@evax.arl.utexas.edu (Col. Ames and Pixel) (09/07/90)
AE showed up at a MCCC meeting here in Arlington and brought a drive
with them. It seemed to work fine. One person who got a early one said he had
trouble with a Mac drive under AMAX plugged into it.
They also said that it appeared as 2 logical devices????? to the system. They
use their own drivers as well. I vote that there is a buffer in there somewhere
because the Paula has a transfer max (could some let us know what it is) that
is too slow for 1.44M drives.
It seems CBM might be working on a 1.44M as well. SYSVR4 has something about
using 1.44M floppies as a standard for transfering data to and fro.
--
adam hill Everybody lies about sex.
hill@evax.arl.utexas.edu BOING!4Ever Rub HER feet!
It's better to copulate than never
AmigaDos2.0 - A VW with $10,000 in options. --Robert A. Heinleindwatts@ki.UUCP (Dan Watts) (09/07/90)
In article <1990Sep7.062756.7556@evax.arl.utexas.edu> hill@evax.arl.utexas.edu (Col. Ames and Pixel) writes: > > AE showed up at a MCCC meeting here in Arlington and brought a drive >with them. It seemed to work fine. One person who got a early one said he had >trouble with a Mac drive under AMAX plugged into it. > > They also said that it appeared as 2 logical devices????? to the system. One of my coworkers has the AE drive on his A500. AE uses two logical devices so that you can access the drive either as a standard density floppy or as a high density floppy. If I recall, you add 4 to the drive number to get the high density access. So, DF2 would be normal density and DF6 would be high density. An interesting thing that we've seen, is that FACCII will work with the high density drive even though FACCII is only designed to handle DF0..DF4. Don't rember what it showed up as, but I think it was DF3. He's also run into compatability problems with some software that don't like accessing drives greater than DF3, but those are few. -- ##################################################################### # CompuServe: >INTERNET:uunet.UU.NET!ki!dwatts Dan Watts # # UUCP : ...!uunet!ki!dwatts Ki Research, Inc. # ############### New Dimensions In Network Connectivity ##############
swarren@convex.com (Steve Warren) (09/07/90)
In article <2915@corpane.UUCP> sparks@corpane.UUCP (John Sparks) writes: >How does the AE drives work anyway? I remember people asking Dave Haynie if >the new version (then called 1.4) of AmigaDOS would support 1.44 meg floppies >and the answer was no, because the chip that handles floppy access could not >support any larger drives. It was a hardware limitation. So, how is AE getting >amigaDOS to support high density drives? They have put a lot of stuff inside that drive, that is why it is more expensive. The drive is not a normal 1.44 meg drive. It has extra controls in it that normal 1.44 Meg drives don't have. The Amiga floppy port cannot directyl control a standard 1.44 Meg floppy. -- _. --Steve ._||__ DISCLAIMER: All opinions are my own. Warren v\ *| ---------------------------------------------- V {uunet,sun}!convex!swarren; swarren@convex.COM
daveh@cbmvax.commodore.com (Dave Haynie) (09/11/90)
In article <2915@corpane.UUCP> sparks@corpane.UUCP (John Sparks) writes: >a72@mindlink.UUCP (Raman Anand) writes: > >>Has anyone tried using Generic 1.44K internal IBM drives with Applied >>Engineering (AE) high density drivers? >How does the AE drives work anyway? I remember people asking Dave Haynie if >the new version (then called 1.4) of AmigaDOS would support 1.44 meg floppies >and the answer was no, because the chip that handles floppy access could not >support any larger drives. It was a hardware limitation. So, how is AE getting >amigaDOS to support high density drives? Well, lemme rephrase that. It's not so much that 1.44 meg floppies are impossible, but that 1.44 meg floppies that work exactly like the IBM 1.44 meg floppies are impossible with the floppy controller in Paula. The specific problem is that the data density of those floppies is twice of what Paula can handle. So you would need some external hardware. Like what? Well, some possibilities: [1] Add an external track buffer and some extra logic. Your floppy mechanism sucks the raw MFM format from the floppy at full speed, feeds it to Paula at her normal speed. Paula shouldn't have too much trouble digesting that much data, as long as it's not coming in so fast as to cause indigestion. [2] Run the floppy drive at 1/2 the normal speed for high density disks. This is basically what old Macs did to get angular bit densities on their outer floppy tracks without having to support higher linear bit densities. Same could work for Amiga style floppies, one would think. [3] Bag Paula entirely and add a PC style floppy controller on a PIC. You might kringe at this prospect as a plain add on, but I bet if one of those "yet another" 3rd party SCSI controllers had glomped on this one relatively cheap extra chip, they would be noticable above the competition. [4] Bag Paula entirely and use a SCSI based floppy disk drive, like the kind they hook up to the NeXT. Only don't charge $1000 for it, and possibly support higher densities as well. >And can CBM maybe license this technology from them and make it an Amiga >standard? You can pretty much figure out what an Amiga-style high density floppy would look like, but options [3] and [4] would force a different format, which could be a problem if Commodore adopts a different format as standard. Then again, if you're the only kid on the block with something people want, you may do well. >John Sparks |D.I.S.K. Public Access Unix System| Multi-User Games, Email -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy Get that coffee outta my face, put a Margarita in its place!
d6b@psuecl.bitnet (09/12/90)
In article <14336@cbmvax.commodore.com>, daveh@cbmvax.commodore.com (Dave Haynie) writes: > >>How does the AE drives work anyway? I remember people asking Dave Haynie if >>the new version (then called 1.4) of AmigaDOS would support 1.44 meg floppies >>and the answer was no, because the chip that handles floppy access could not >>support any larger drives. It was a hardware limitation. So, how is AE getting >>amigaDOS to support high density drives? I assume they're doing GCR at 2us/bit (it's possible...I've done it). (With 2meg drives, of course; it doesn't work at all on 1meg drives). You should be able to use their software with any 2meg drive. (Although they could be using those strange sony drives that Apple uses to store slightly more than you would normally get with 2us GCR). [lots of good stuff by Dave deleted] You left out an option - improve Paula. As explained in an earlier posting, if you incorporated MFM encode/decode onto Paula, the memory bandwidth requirements for 1us/bit MFM would be exactly the same. I don't think the clock would be a problem...so it's a drop-in upgrade. Why not do it??? -- Dan Babcock P.S. This system (a VAX!) crashes every time I do a followup (register dump, etc.). An email note saying "Yep, it went out" would be appreciated... thanks. > Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" > {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy > Get that coffee outta my face, put a Margarita in its place!