Date   : Thu, 26 Feb 1998 16:30:45 GMT
From   : Chris Thornley <osu036@...>
Subject: Re: __CATALOG__ files

On Thu, 26 Feb 1998 16:57:57 +0100 Robert Schmidt wrote:

> From: Robert Schmidt <rsc@...>
> Date: Thu, 26 Feb 1998 16:57:57 +0100
> Subject: Re: [BeebEmul8] __CATALOG__ files
> To: Tom Seddon <T.W.Seddon@...>
> Cc: beeb-emulators@...
> 
> > Spaces aren't handled in my conversion utilities at least, and not in my
> > emulator, because the original Beeb didn't support them either. Actually
I
> > cheat a bit here, because they could be handled fine, but by sticking
> > closely to the BBC I make things easier for myself and am able to
say it's
> > a good thing ;-)
> 
> Hmmm... I seem to recall that files on tape could have spaces.  I am, of
> course, unable to verify this... :)  DFS file names were more limited
> than those on tape: specifically the maximum length was shorter, and
> files on tape could very well have the same name.
> 

Theres a comerical tape I have called ghouls on this there a file called
?.??????
which the program need to load. I was unable to transfer this program
to disc due to the tape version having a 
ascii charter code inplace or one of the question markes.
Also on the bbc lives page some of the disc images in the watford section
produce info and file name which 
have a hiden or unusall ascii charter which means they are a pain in
the neck to delete of the hd or copy edit or 
do anything with until I run norton disc editor to correct the offending
name.



> Which brings me to a field I forgot to mention:
> 
> NEXT=<file>
> 
> This specifies the name of the next file (dumped from tape).  Some tape
> programs load their parts by using CHAIN "" or "*RUN" - which doesn't
> work on DFS.  The NEXT-field at least tries to give an indication as tho
> the sequence in which files were found on the tape.  But it is useless
> if files have the same BBC names...  NEXT should somehow point to the
> correct "*.inf" file, I guess.

Yeap I have seen this in a lot of tape programs files with the same name
perhaps there should be a numbering 
sequence included as well.

>  
> > Isn't the CRC field now obsolete?
> 
> Not that I know of... it was always optional in the first place, and
> Wouter liked having it so that he could verify correctness of files
> transferred from his BBC.  That said, I tried arguing against it... :)
> 
> Also, Wouter specified the field
> 
> LOCKED (shorthand "L" permitted)
> 
> for ... uhmmm... locked files.
>
Some tape program could be locked on tape i.e you could not copy them
only run them because there lock 
atribute was set. The only way round this was either to run locksmith
or a rom which specializes in tape 
transfer. The enigma disc imager rom can create locked and unlock certain
types of locked programs

Another tape trick was to alter the baud rate part way through loading
i.e from 1200 to 300 baud and back agin 
for say one block such programs where probally load through bget or other
machine code based loaders
 
There are also programs with no header. So probally *opt 2,1 or 2,0 to
supress error messages had to be done 
to load these or a false lead tone would have to be crated or something
to load these files. These had custom 
loaders.

There was a program called basic code developed which allowed programs
to be transfered into a standard 
tone so that they could be loaded on other varietires of computers Does
anybody have a copy of the tape with 
the other versions of the program which was intended for various computers.
I belive it might have been 
developed by a university but I can rember as I can not locate my photo
copy of its manual.  I only have the 
bbc version of basicload a and basicsave.



               />      Christopher J. Thornley is OSU036@...
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