diff --git a/mandel.s b/mandel.s
index 7c5c652..fe29001 100644
--- a/mandel.s
+++ b/mandel.s
@@ -1148,11 +1148,13 @@ skip_char:
     rts
 
 plus:
+    lda zoom
     cmp #8
     bpl skip_char
     inc zoom
     jmp done
 minus:
+    lda zoom
     cmp #1
     bmi skip_char
     dec zoom