Re: A82: Some Questions

To: assembly-82@lists.ticalc.org
Subject: Re: A82: Some Questions
From: Dines Christy Justesen <c958362@student.dtu.dk>
Date: Wed, 12 Nov 1997 14:43:11 +0100 (MET)
Reply-To: assembly-82@lists.ticalc.org

>>2. Would it be possible to make a timer on the calculator ?
>
>I think so, but _how_ to do it is beyond by horizon, although I think
Dines
Justesen has written an ASH program which hooks the timer interrupt.

Writing a program which uses the timer interrupt is not problem (have a
look
at IntTest82), the problem is that the speed of the calc varies. However
test on the TI85 shows that if you initialize the rutine correct before
you
start you can make an ok timer, but it wont be very precise since when you
use it the calc will get slower and slower so you have to reinitialize now
and then. To initialize the timer in the calc you would need a
timer/clock,
and if you have that you do not need the timer on the calc.

Dines

BTW there are lots of easy to understand interrupt rutines written for the
TI85, and they are very similar to what you do on the ti82. IntTest82 was
my
first interrupt driven program, and i made that using source from the
ti85.


_______________________________________

Dines Justesen
Email: dines@post1.com or
       c958362@student.dtu.dk
WWW  : http://www.gbar.dtu.dk/~c958362/
_______________________________________