Matrix at 2x Speed!

Matrix on the C64 is deliberately slow. With the following simple patch we can tune it to be twice as fast, and to my taste, even more enjoyable to play.

diff --git a/src/c64/matrix.asm b/src/c64/matrix.asm
index de54195..37ea478 100644
--- a/src/c64/matrix.asm
+++ b/src/c64/matrix.asm
@@ -1000,7 +1000,7 @@ AnimateCurrentBullet
         BEQ b8535
 b8534   RTS 
 
-b8535   LDA #$20
+b8535   LDA #$09
         STA bulletFrameCounter
 
         ; Play Bullet Sound
@@ -1543,7 +1543,7 @@ AnimateZapperTail
         ROL 
         ADC #$00
         ;FIXME: should this be charSetLocation + $0109 like in Vic20?
-        STA f1509
+        STA charSetLocation + $0109
         RTS 
 
 ;-------------------------------------------------------------------------
@@ -1635,7 +1635,7 @@ AnimateDroidSquads
         BEQ b8947
 b8946   RTS 
 
-b8947   LDA #$C0
+b8947   LDA #$60
         STA droidAnimationFrameRate
         JSR AnimateSnitch
         LDA noOfDroidSquadsLeftInCurrentLevel