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mcgeezer · 10 November 2021, 20:20

I would probably have used eor.b #1,d0

As an aside I tend to have to do this a lot in my stuff, so I always opt to use a frame counter when doing it.

Code:

loop:
  WAIT_FOR_FRAME

  addq.l #1,FRAME_COUNTER

  move.l FRAME_COUNTER,d0
  and.l #1,d0
  beq  do_something
  bra  do_something else

  bra loop

I really would look to learn the inner workings of 68k. When I was younger I didn't pay any attention to status flags, I also didn't pay attention to detail on not, neg and particularly the effects of ext. The set instructions are all useful too.

10 November 2021, 20:20	#4
mcgeezer Registered User Join Date: Oct 2017 Location: Sunderland, England Posts: 2,702	I would probably have used eor.b #1,d0 As an aside I tend to have to do this a lot in my stuff, so I always opt to use a frame counter when doing it. Code: loop: WAIT_FOR_FRAME addq.l #1,FRAME_COUNTER move.l FRAME_COUNTER,d0 and.l #1,d0 beq do_something bra do_something else bra loop I really would look to learn the inner workings of 68k. When I was younger I didn't pay any attention to status flags, I also didn't pay attention to detail on not, neg and particularly the effects of ext. The set instructions are all useful too. Last edited by mcgeezer; 10 November 2021 at 22:47. Reason: thanks jotd for pointing out silly code error