NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/sys/amiga/programmer/3525

Internet Message Format | 1996-08-05 | 4.8 KB

Path: severus.mbfys.kun.nl!rhialto
From: [e-mail] (Olaf Seibert)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: Is there a way to read Amiga disks on a PC?
Date: 21 Feb 1996 16:04:40 GMT
Organization: University of Nijmegen, The Netherlands
Distribution: world
Message-ID: <4gffqo$[e-mail]>
References: <4gaolc$[e-mail]>
NNTP-Posting-Host: severus.mbfys.kun.nl

In article <[e-mail]>,
   Gint Grabauskas <gint> wrote:
>Hello,
>
>I am currently looking for a utility that will allow the reading of
>Amiga disks on a PC.  I have found utilities that read MAC disks and Atari
>ST disks on a PC, but not that read Amiga on a PC. If anyone is aware of
>such a program,

Here is (again...) a repost of the authoritative article about this
subject.

| Article 32868 of comp.sys.amiga.tech:
| Path: sci.kun.nl!hp4nl!mcsun!uunet!cbmvax!daveh
| From: [e-mail] (Dave Haynie)
| Newsgroups: comp.sys.amiga.tech
| Subject: Re: Read & Write from/to Amiga disks on a MS-DOS machine
| Message-ID: <[e-mail]>
| Date: 4 Jan 91 22:19:19 GMT
| References: <[e-mail]>
| Reply-To: [e-mail] (Dave Haynie)
| Organization: Commodore, West Chester, PA
| Lines: 54
|
| In article <[e-mail]> [e-mail] (Robert Hartill) writes:
| >Is there an equivalent program to MSH to use Amiga disks on a MS-DOS machine ?
|
| >What I want to do is use kermit on a PC to transfer Amiga PD from our
| >vax. My Amiga is not 'on-site' so it has to be via a PC.
|
| No.  There are two good reasons for this.  First of all, most, if not all,
| PClones, are incapable of reading Amiga disks at the hardware level.  While
| they use compatible low-level MFM formats, the Amiga always does full track
| read/write, while the standard PC is sector based.  The Amiga can easily
| create equivalent sectors in software (yielding 9 physical sectors/track),
| rather than going sectorless (yielding 11 logical sectors/track).  The PC
| can't deal with the lack of sectors.  While it's possible that some PC
| somewhere does full track buffering and might allow Amiga disks to be read,
| I doubt it -- the whole PC industry tends to pick a single hardware level
| chip definition, whether for keyboard controller, floppy, hard disk, video,
| etc. and stick with it, clone it, etc.
|
| Which brings us to the second problem, that of device independence.  All
| Amiga DOS level devices (DF0:, RAM:, etc.) are fully device independent.  You
| can have a lower-level device driver and use the same file system over a
| large number of devices (like FFS does), or you can have a filesystem that's
| specific to a particular subsystem (like RAM:).  MS-DOS, on the other hand,
| doesn't support true device independence.  To read an Amiga disk as easily
| on an MS-DOS machine as MSH: does on an Amiga, you would need two new pieces
| of software.  First of all, you'd need a device driver which makes your floppy
| disk drive read Amiga formatted disks, rather than MS-DOS disks.  That's the
| analog of MSH's "messydisk.device".  Then you would need a mountable filesystem
| for the Amiga disk format, the analog of "messyfilesystem".  Far as I know,
| you could do this under OS/2, but not under MS-DOS, hardware permitting (which,
| as I mentioned above, is impossible on the average PC, if not all of them).
|
| If the underlying hardware supported it, you could possibly make like the
| "PCUtilities" under AmigaDOS, the Apple File Exchange thingy under MAC OS,
| or some of the "DOS2DOS" kind of things available for the Amiga, and write a
| dedicated program, rather than the more flexible device/filesystem, to read
| Amiga disks at the program, rather than OS, level.  Unfortunately, the PC
| hardware is going to make this impossible.  It may be possible to read Amiga
| disks with the emerging SCSI-based floppy drives.  I don't know for sure, but
| it's typical of SCSI devices to do full track buffering, so if the programming
| model for these devices allows you to decode 11 sectors rather than 9, it
| should be possible.  However, SCSI itself is very rare on MS-DOS machines these
| days, SCSI floppies are practically unheard of.
|
| >::     Robert Hartill, Dept Of Computing Mathematics, UWCC, Cardiff, UK.     ::
| >::                       e-mail : [e-mail]                            ::
|
|
|
| --
| Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
|    {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
|     "Don't worry, 'bout a thing. 'Cause every little thing,
|      gonna be alright"        -Bob Marley

-Olaf.
--
___ Olaf 'Rhialto' Seibert    [e-mail]     Ooey-Gooey-Fluffy-Barfie
\X/ I'm not weird, I'm differently percepted. D787B44DFC896063 4CBB95A5BD1DAA96