Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!iowasp.physics.uiowa.edu!syswtr
From: syswtr@iowasp.physics.uiowa.edu
Newsgroups: comp.os.cpm
Subject: Re: CP/M disk formats (was Re: CPM to DOS exchanger)
Message-ID: <1991Jun7.090223.847@iowasp.physics.uiowa.edu>
Date: 7 Jun 91 09:02:23 -0500
References: <1991May22.042049.8842@trl.oz.au> <Z8cR31w164w@ruth.UUCP> <822@spam.ua.oz> <1991Jun7.064252.13117@monu1.cc.monash.edu.au>
Organization: Department of Physics and Astronomy, University of Iowa
Lines: 37

In article <1991Jun7.064252.13117@monu1.cc.monash.edu.au>, rjl@monu1.cc.monash.edu.au (    r    lang) writes:
> In article <822@spam.ua.oz>, dcook@spam.ua.oz (David Cook) writes:
> Clarence Wilkerson writes:
>> If the 3.5" disk is physically compatible with ibm pc type
>> drives, then you can hack a set of parameter tables to match
>> them and use 22disk, a shareware program that runs on a PC.
> I have tried this and it didn't work.
> I have two theories, neither has been tested.
> 1. Microbee disks have 10 sectors and the intersector space
>    is shorter than specified in the Western Digital data sheet.
>    The PC may not like this short space.
> 2. I think (but am not sure) that the sector header information
>    is marked side 0 for both sides of the disk.  
>    If the PC insists that side 1 is marked as side 1 ...

 On item 2:

  The SMC floppy controller on the SB180 (a '765 look-alike) is capable
of reading diskettes that have the side bit in the sector header wrong.
I don't know if the NEC or Intel chip acts the same, but if so the 
following may help:

	Write command:
			Command
			Unit/Head (controls hardware lines)
			Cyl
			Head (controls what is to/from disk)
			Record
			Size
			EOT
			GPL
			DTL

  On the FDC9266 setting the 'Unit/Head' bit to side one and the 'Head'
byte to side zero does work.

Willy