Re: A86: interrupt test program


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Re: A86: interrupt test program




> Alright, it's pretty simple, really. If bit 2,(iy+$23) (35 decimal) is set,
> the interrupt routine (rst 38h) will call a user interrupt routine every
> time it gets called (200 times a second, or something). The interrupt
> routine goes in a special 200 byte area of the ram, $d2fe-$d3c5.
> 
> So you just res 2,(iy+$23), then copy your interrupt routine to $d2fe. The
> byte at $d2fd is a checksum byte of sorts, you have to set it to
> ($d2fe)+($d325)+($d34d)+($d375)+($d39d)+($d3c5). Then you set 2,(iy+$23),
> and the routine gets called every time an interrupt happens.
> 
> Actually, you don't even have to write the code yourself - just use testint
> and replace everything after the int: label with your own routine.
> Variables after the int label be declared like this:
> var equ $-int+_user_int_ram+1
>    .db (or .dw)
> instead of like this:
> var:
>    .db

o now i c, i was tryin to put a string at the end and thats what was
screwing it up (putting garbage on the screen 200 times a second :)


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