Re: A86: User interrupt question

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Re: A86: User interrupt question

 

Garcia wrote:

What exactly is the process for the calc calling the user interrupt.  Does
it go to $38, than jumps to $D2F2?
Sort of.  It calls $d2fe, but only if the right flag is set.  I'm not sure when rst 38h is called though.
Then how does it end?
With a ret somewhere down the line.
 The following are
stupid question I've never bothered asking:

1.  Can you have an interrupt durring and interrupt?

Not unless you call $d2fe from within your interrupt  :-)
 Is this limit by the
number of clock cycles in my interrupt?
I'm not sure what you mean.

2.  Can I use regular ROM calls in:
        1. The user interrupt and all other user areas?

Set the page first.

        2. The interrupt using IM 2 and the 257 byte table?

I've never heard of IM 2.
3. Has anyone found a way to execute an assembly program from within an
interrupt or immediately after?
Depending on your application, you can probably use [sqrt]KEY.  Plus, [sqrt]KEY is more efficient than the interrupt because it's only called after _getkey and not 200 times a second, meaning that it doesn't slow down parsing, graphing, programs, etc, when you generally don't need to check anything at those times.  Asm programs will execute perfectly from within [sqrt]KEY.  If you really need to use the interrupt, though, or one of the routines just like it, set a flag in the interrupt and check it in [sqrt]KEY.
 

Andres Garcia
---------------------
xrigel@q-net.net

 
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