Re: A82: Re: Pointers and shells


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Re: A82: Re: Pointers and shells



Based on what Dines just said, and what I've seen in the Ash 2.0 file, here is
what I think happens:

When in the home screen, the calc is in a KEY_HAND loop. There is a table in
memory, like this:

K_MODE    $2335
K_ENTER    $2453

If it gets the scan code for mode, it will do a call $2335. If it gets that of
enter, it will do a call $2453. The matrix L1 is the location of the ash object
code, a couple bytes into user memory. L2 is the location in memory of the
right side of the table for K_ENTER. L1 is loaded into L2, so the next time you
press enter, it will not compute the answer, but it will call ash. Get it?

Eric O'Connell wrote:

> >Dines
> >
> >BTW I hope you understud the part about how shells are implemented, if not
> >just ask :)
>
> Hmm.. i understand everything but how exactly you change the input handler
> only by running the ASH program.  i know this has something to do with the
> hacking of the backup file, but if it's an input handler.. hmm.  do you
> understand what i'm asking? :)
>
> eric
>
> +----------------+------------------+
> | Eric O'Connell |  Mac Programmer  |
> +----------------+    Guitarist     |
> | titan@gate.net |  Math Hobbiest   |
> | drdistort(irc) | Insensitive Male |
> +----------------+------------------+
> | web:  http://www.gate.net/~titan  |
> +-----------------------------------+




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