ScanLine Color Interrupt
6 messages in this thread
Anybody point me to a code fragment to change the color map at a vertical
scanline? Thanks.
I don't believe there is a horozontal blank interrupt. I have heard that
you can fake it via. timer interrupts and a phase-lock-loop to trigger the
palette change. However you can't even modify 256 colors during vertical
blank fast enough, most VGA cards "farkle" when you do this (direct
register writes).
Good luck Doug…
William Volk
Doug,
The best way to modify the color map at a specific scan line is by
using a copper list. The hardware reference manual gives the information
needed to do this. I dont know if there is any example code in the
libraries, I may have some here I could upload if you cant find anything.
– Andrew
Some example code would be a real help. Thanks.
look for files with the keyword copper, and maybe source… there are some
here.
Doug,
I looked through my disk library last night, and found some example
assembler code for setting up a copper list. The particular examples I
found dont do exactly what you are looking for, but it would be very easy
to change. Have a look in the libraries for files with the keyword
'COPPER', if you cant find anything let me know and I'll knock up an
example to upload.
– Andrew