Re: A86: Capture key-press
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Re: A86: Capture key-press
Jimmy Mårdell wrote:
>
> At 13:31 1997-11-19 +0100, you wrote:
> >I just wondered if something like this would be possible to do:
> >Write an interrupt that would monitor keypresses during normal calc
> operation, and run a >specific code if a certain key is pressed. As far as
> I have understood, interrupts aren't >easy to do, but if somebody have any
> experience, please let me know.
>
> As you say, runlength interrupt handlers are easy, but TSR programs
> (interrupts still
> running after you quit the program that 'hooked' it) are, as far as we
> know, kind
> of hard. Or at least, they will be unstable.
>
> If you want to use IM 2, you'll have to store a 257 byte vector table +
> interrupt handler
> somewhere in the RAM which doesn't change. That would be at the end of
> _asm_exec_ram
> or something. This wouldn't be too hard if we knew how to allocate memory
> at the end
> of the _asm_exec_ram as the TI financial program does.
>
> I still suspect that TI might have added some support for creating
> interrupt handlers
> without using IM 2 (since there is a call in the interrupt handler at 38h
> to a location
> in the RAM which could be changed).
>
maybe some way to point it to the address after it does a check for the
ON button?
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