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--- base:launching_long_tasks_from_irq_handler [2016-03-15 12:33] – bitbreaker
+++ base:launching_long_tasks_from_irq_handler [2016-11-23 10:54] (current) – bitbreaker
@@ Line 76: / Line 76: @@
         sta $d012
-        ;now allow irq2 happen on top of this task and return to this task when done
+        ;now allow irq2 to happen on top of this task and return to this task when done
         cli
@@ Line 110: / Line 110: @@
         rti
 </code>
+A even more convenient variant is to use the stack for register saving:
+<code>
+irq1
+        pha
+        txa
+        pha
+        tya
+        pha
+        dec $d019
+        dec counter
+        bne +
+        lda #$08
+        sta counter
+        cli
+        jsr long_task
++
+        pla
+        tay
+        pla
+        tax
+        pla
+        rti
+</code>
+Now you can run a long task that can finish somewhen between the next 8 interrupts.