Path: utzoo!attcan!uunet!bellcore!att!pacbell.com!pacbell!well!farren
From: farren@well.sf.ca.us (Mike Farren)
Newsgroups: comp.sys.amiga.tech
Subject: Re: MFM/IBM Decode
Message-ID: <22112@well.sf.ca.us>
Date: 11 Dec 90 12:31:35 GMT
References: <49724@eerie.acsu.Buffalo.EDU>
Lines: 23

v089pfrb@ubvmsd.cc.buffalo.edu (Jeffrey C Murphy) writes:
>       1) I know about decoding MFM formats, but what is the IBM decode
>algorithm?

Hmm?  IBM decode?  Do you mean GCR?  IBM diskettes use a standard MFM
decode, but a different data format than Amiga disks.  

>       2) Do you have to bypass DOS in order to read a foriegn format?

Generally.  DOS knows nothing about any other formats, except that there
is the PCCopy program included with 1.3 - but then, it bypasses the normal
disk routines, anyhow.

>       3) Amiga Disk Drives Inside & Out (Abacus) seems to use many
>absolute addresses in its programming examples, why?

Because they are stupid.  The folks that put out the Abacus books don't
know thing one about how the Amiga really works - they seem to think
that it's just some fancy C64.  Avoid using their examples, unless you're
willing to rework them to be "Amiga-friendly" (not always possible).

-- 
Mike Farren 				     farren@well.sf.ca.us