Path: utzoo!attcan!uunet!mcvax!nikhefk!henkp
From: henkp@nikhefk.UUCP (Henk Peek)
Newsgroups: comp.os.minix
Subject: Re: Minix/MessDOS disk formatting.... please HELP!
Message-ID: <371@nikhefk.UUCP>
Date: 24 May 88 02:09:07 GMT
References: <1512@runx.ips.oz>
Reply-To: henkp@nikhefk.UUCP (Henk Peek)
Organization: Nikhef-K, Amsterdam (the Netherlands).
Lines: 23

In article <1512@runx.ips.oz> johnf@runx.ips.oz (John F. Baird) writes:
-I am desperately trying to get my 68000/Z80 based system to format a disk for
-use with MSDOS/Minix. The system uses a WD1772, rather than the NEC uPD765
-used in the IBM PC, and I think this may be the problem. The WD1772 has no
-trouble at all reading and writing MSDOS disks; It can read the disks that it
-formats too.
-The WD1772 seems far less picky about what it will and won't read. After I
-format a disk on it and initialize it with an MSDOS filesystem, the IBM PC
-gives "General Failure" or "Not Ready" errors - but several retries gets it to

-What am I doing wrong?. Has anyone got the source for a diskette formatting

Yes there is a format problem. The WD FD controllers writing the first
address mark under the index hole and the 765 can't find a address mark
in the index pulse (index hole). (It writes its first address mark
after the index hole :-)
There is an easy cure to read a WD formatted floppy with a 765 controller:
Put a small sticker over the index hole on the floppy disk jacket.
The 765 can now search the hole trac for address marks. Only when
something goes wrong the floppy controller doesn't timeout.
(The timeout function counts ~3 index pulses.) You could use alarm().

Henk Peek ..!uunet!mcvax!nikhefk!henkp.UUCP