3.5" Altair CP/M

[Grant Stockly]

At 05:28 PM 5/15/2007, you wrote:
>On Tue, 15 May 2007, Grant Stockly wrote:
> > Its an MDL-1011D with an FD1771-B01.
> > What's the deal with this chip?  Is it formatting the the disk as 360k?
>
>Nothing special.  It is a SINGLE DENSITY (FM) ONLY chip.
>Although it might give a final capacity of 360K or thereabouts,
>It's parameters are most certainly NOT the same as the IBM "360K" format.
>It is most likely formatting it as 10 256 byte sectors per track,
>or as 18 128 byte sectors.
>Tools for looking at MFM disks would be looking for MFM. NOT FM, and would
>prob'ly default to expecting 512 bytes per sector.

I found that I have to cover the hole or I get BDOS erros about missing 
sectors.  I figured it wouldn't look for the hole...

A freshly formatted disk gives me this:
A>STAT B:

BYTES REMAINING ON B: 69K

A>

69k for a 1.4MB disk!  I was ripped off!  : (  It is running CP/M 1.4.  I 
have the sources if anyone is interested.

This is what it says when it boots up:

TARBELL 24K CPM V1.4 OF 7-20-79
2SIO MINIFLOPPY VERSION.
HOW MANY DISKS? 2
A>

Were single sided single density 5.25" disks ~70k?  The 3.5" drive does 
sound different than it usually does.  : )