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--- base:frame_skipping [2014-11-11 12:50] – created mace
+++ base:frame_skipping [2015-04-17 04:32] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== Frame skipping ======
+Once in a while you created some effect that just goes too quick when you update it every frame.
+The option is to have a check in order to skip your routine every other frame.
+Put this inside your IRQ.
+<code>
+start:
+   inc skipper+1      // increase the check byte
+skipper:
+   lda #$00           // check byte
+   and #$01           // check first bit (even or odd number?)
+   beq passroutine    // skip routine on even numbers
+routine:
+   // routine that will be executed every other frame
+passroutine:
+   // the rest, executed every frame</code>