Need information on TRSDOS 1.3 internals

From: Chandra Bajpai <cbajpai_at_attbi.com>
Date: Fri Dec 6 06:56:00 2002

All these terms are waking up old memories (and brain cells) from my
youth...I used to do some low level programming as a kid on TRSDOS 1.3
in my parent's basement. Thanks for the pleasant memories.

-Chandra


-----Original Message-----
From: cctalk-admin_at_classiccmp.org [mailto:cctalk-admin_at_classiccmp.org]
On Behalf Of Tony Duell
Sent: Thursday, December 05, 2002 6:44 PM
To: cctalk_at_classiccmp.org
Subject: Re: Need information on TRSDOS 1.3 internals

> Each track had 10 sectors. They were allocated to files in groups of
> five, which were called granules or grans. There's a Granule
Allocation
> Table (GAT) which I think was basically an allocation bitmap.

TRS-DOS 1.3 ran on the model 3 which used double density (MFM)
recording.

IIRC, there are 18 sectors per track, and 6 sectors per granule (I think

it's 6, not 9).

The GAT is much the same on all versions of TRS-DOS, as is the HIT (Hash

Index Table -- which relates a hashed form of a filename to the
directory
entry that contaisn the info for that file).

-tony
Received on Fri Dec 06 2002 - 06:56:00 GMT