Re: LZ: Cassette system


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Re: LZ: Cassette system



On 16 Sep 96 at 11:08, Jarkko V=E4=E4r=E4niemi wrote:


> I'm going to try to build that hardware system (walkman adapter) that 
> I posted here some time ago. (At least I'll order those parts ;-)
> If anyone would know how to make a new variable within Zshell, or 
> would like to make this program, contact me!


The way to create a variable in ZShell is to call the Create Variable
routine in ROM. There are a couple of things you have to consider
though. First, the call address is different on all different ROM
versions. (I don't even know if it's known on all..). 


The other thing is that when the routine is executed, it may move
the variables in RAM around. If the string variable containing the
calling program is moved, the ret adress from the routine becomes
wrong.. 


Both these _can_ be solved but as you see, it's a bit problematic. 
I'd wait for the next version of ZShell, which is said to support 
variable management.


<pre>
--
 Mattias Lindqvist
 d96mli@efd.lth.se
 www.efd.lth.se/~d96mli
</pre>


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