diff --git a/mandel.s b/mandel.s
index 44bff1f..42982cb 100644
--- a/mandel.s
+++ b/mandel.s
@@ -489,7 +489,7 @@ initloop:
     dex
     bne initloop
     sta z_buffer_start
-    sta z_buffer_len
+    sta z_buffer_end
 
 loop:
     ; iter++ & max-iters break
@@ -905,7 +905,7 @@ loop_sx:
     cmp #$ff
     beq skip_char
 
-    ; Clear the keyboard buffer
+    ; Clear the keyboard buffer and re-enable interrupts
     ldx #$ff
     stx CH