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From: mj@myrias.UUCP (Michal Jaegermann)
Newsgroups: net.micro.ti
Subject: Re: TI-994/A Editor Assembler
Message-ID: <200@myrias.UUCP>
Date: Mon, 30-Dec-85 14:20:10 EST
Article-I.D.: myrias.200
Posted: Mon Dec 30 14:20:10 1985
Date-Received: Mon, 30-Dec-85 17:24:38 EST
References: <166@pyuxv.UUCP> <720@houxu.UUCP> <169@aero.ARPA>
Organization: Myrias Research, Edmonton
Lines: 26

> I have been reading to and writing from a disk OK in assembly language. 
> However I have not been able to figure out how to read the disk directory.
> Can Robert Switzer or anyone else on the net tell me how to do it.

[ reply is news, since mail bounced at ittatc ]

There are basically two ways. The first one - if you are able to read
disk on sector-by-sector basis. Read sector 0 and extract all
information about disk - name, format, number of sectors, used (this
have to be computed from a bit-map table). Read sector 1. You will get
up to 127 pointers to sectors which contain file information. Read all
sectors with non-zero pointers to extract file information. This method
will may reveal all "hidden" files, which pointers follow a null
pointer.
The second one. Open a file with an empty name like "DSK1.". This is -
if I remeber correctly - internal, fixed 38 with record fields: string
followed by 3 numbers. Record #0 will give you a disk information.
Subsequent records will hold file info. I do not remember a meaning of 
numbers, but quick experiment in Basic with a known disk will reveal
that (negative type if protected). Since this is a standard Basic file,
thus all numeric entries are in a floating point format. This will give
you a slight headache if you will be reading the stuff in assembler.
=============================
Michal Jaegermann
Myrias Research Corporation
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