Set up an IM2 vector table, use the frame interrupt to set up the first line interrupt (send the line number you want to fire to port $f9), then have your line interrupt routine set up the second time it should trigger by sending the new line number again to port $f9.
I do that more or less for my special edition version of lost disks of sam I've been tinkering with for a while now, only inside an IM1 interrupt routine. Seems to work absolutely fine so far, although I don't know if it would be considered the "right" way. Probably not, but if it works, I'm happy as larry. Happy new year:) Andrew ----- Original Message ----- From: Andrew Park To: sam-users@nvg.ntnu.no Sent: Wednesday, January 01, 2014 3:37 PM Subject: Line interrupts Hi all Happy new year lets hope we can see some more sam stuff this year. Any idea how i can set up a line interrupt routine between 32768 and 65535? I want to change the palette twice once at line 0 and then again on line 128. Many thanks Andy
