[Coco] tape format and .cas file problems

[Ciaran Anscomb]

Roger Taylor wrote:
> At 08:38 AM 11/19/2008, you wrote:
> 
> Probably overkill.  Also, CLOADM only supports one start address as 
> far as I recall.  This means the entire ML program has to be 
> contiguous, unlike the multi-record LOADM format which can jump all 
> around RAM doing what it wants.
> 
> I remember back in the 80's seeing Rainbow magazine ads selling CoCo 
> tricks like "Auto executing tape programs" but I could be wrong.  I'd 
> like to know how a lowly 16k or even 4k CoCo 1 could do this just by 
> typing CLOADM.  I don't see anything in the tape format that allows 
> for such a trick.

A pretty standard trick that I've used myself is to have the first loaded
binary patch over either the area of RAM that executes "next statement"
or the IRQ vectors or similar.  Loading multiple blocks is fairly easy
once you've got your initial autorun.

I've also, oddly enough, used this to make loading quicker:

http://www.6809.org.uk/tmp/da/impossiball-coco.wav.gz
http://www.6809.org.uk/tmp/da/utopia-coco.wav.gz

With some notes on what it does here:

http://www.6809.org.uk/tmp/da/utopia_iball_coco.txt

..ciaran
-- 
Ciaran Anscomb, Perl/C Hacker