Finish up work on the scorpion, adding support for shooting the scorpion. Some more cleanup of hard coded constants, moving them to globals.

BuGS/game.s

@@ -599,21 +599,21 @@ drawAll entry
         
 setupScreen entry
         short i,m
-        lda $e0c035     ; Enable shadowing of SHR
+        lda >SHADOW_REGISTER     ; Enable shadowing of SHR
         and #$f7
-        sta $e0c035
+        sta >SHADOW_REGISTER
         
         lda #$a1
-        sta $e0c029     ; Enable SHR mode
+        sta >NEW_VIDEO_REGISTER     ; Enable SHR mode
         long i,m
         
         sei
         phd
         tsc
         sta backupStack
-        lda $e1c068      ; Direct Page and Stack in Bank 01/
+        lda >STATE_REGISTER      ; Direct Page and Stack in Bank 01/
         ora #$0030
-        sta $e1c068
+        sta >STATE_REGISTER
         ldx #$0000
         
         lda #$9dfe
@@ -625,9 +625,9 @@ nextWord anop
         dey
         bpl nextWord
         
-        lda $e1c068
+        lda >STATE_REGISTER
         and #$ffcf
-        sta $e1c068
+        sta >STATE_REGISTER
         lda backupStack
         tcs
         pld
@@ -640,9 +640,9 @@ nextWord anop
 checkKeyboard entry
 checkKey_loop2 anop
         short i,m
-        lda $e0c000
+        lda >KEYBOARD
         bpl checkKey_done
-        sta $e0c010
+        sta >KEYBOARD_STROBE
         long i,m
         and #$007f
         
@@ -665,7 +665,7 @@ checkKey_loop2 anop
         
         lda colourPalette
         inc a
-        cmp #$000e
+        cmp #NUM_COLOUR_PALETTES
         blt checkKey_skip
         lda #$0000
 checkKey_skip anop
@@ -694,9 +694,9 @@ checkKey_done anop
 waitForKey entry
         short i,m
 waitForKey_loop anop
-        lda $e0c000
+        lda >KEYBOARD
         bpl waitForKey_loop
-        sta $e0c010
+        sta >KEYBOARD_STROBE
         long i,m
         rtl
 
@@ -705,10 +705,10 @@ waitForVbl entry
         short i,m
 vblLoop1 anop
         lda #$fe
-        cmp $e0c019
+        cmp >READ_VBL
         bpl vblLoop1
 vblLoop2 anop
-        cmp $e0c019
+        cmp >READ_VBL
         bmi vblLoop2
         long i,m
         rtl

BuGS/gameScorpion.s

@@ -158,7 +158,7 @@ updateScorpion entry
         
 updateScorpion_cont anop
         cmp #SCORPION_STATE_EXPLODING
-        bra updateScorpion_notExploding
+        bne updateScorpion_notExploding
         jmp updateScorpion_exploding
 
 updateScorpion_notExploding anop
@@ -243,6 +243,7 @@ updateScorpion_maybePoison anop
 
         ora #TILE_POISON_A_MUSHROOM
         sta tiles+TILE_TYPE_OFFSET,x
+updateScorpion_done anop
         rtl
         
 updateScorpion_offScreen anop
@@ -250,9 +251,15 @@ updateScorpion_offScreen anop
         rtl
 
 updateScorpion_exploding anop
-; Write this code
-
-updateScorpion_done anop
+        lda scorpionSprite
+        beq updateScorpion_explosionDone
+        sec
+        sbc #$4
+        sta scorpionSprite
+        rtl
+        
+updateScorpion_explosionDone anop
+        stz scorpionState
         rtl
         
         
@@ -362,7 +369,18 @@ addScorpion_done anop
         
 
 shootScorpion entry
-; TODO - Write this code
+        lda scorpionState
+        beq shootScorpion_done
+        cmp #SCORPION_STATE_EXPLODING
+        beq shootScorpion_done
+        
+        lda #SCORPION_STATE_EXPLODING
+        sta scorpionState
+        
+        lda #EXPLOSION_LAST_OFFSET
+        sta scorpionSprite
+        
+shootScorpion_done anop
         rtl
 
 

BuGS/globals.s

@@ -118,6 +118,15 @@ TILE_BELOW_OFFSET           gequ 8
 TILE_LEFT_OFFSET            gequ 10
 TILE_RIGHT_OFFSET           gequ 12
 
+NUM_COLOUR_PALETTES     gequ 14
+
+KEYBOARD                gequ $e0c000
+KEYBOARD_STROBE         gequ $e0c010
+READ_VBL                gequ $e0c019
+SHADOW_REGISTER         gequ $e0c035
+NEW_VIDEO_REGISTER      gequ $e0c029
+STATE_REGISTER          gequ $e1c068
+
 
 backupStack dc i2'0'
 

BuGS/sprites/sprites.macros

@@ -11,9 +11,9 @@
         sei
         tsc
         sta backupStack
-        lda $e1c068      ; Direct Page and Stack in Bank 01/
+        lda >STATE_REGISTER      ; Direct Page and Stack in Bank 01/
         ora #$0030
-        sta $e1c068
+        sta >STATE_REGISTER
         clc
         tya
         tcs
@@ -22,9 +22,9 @@
 
         macro
         _spriteFooter
-        lda $e1c068
+        lda >STATE_REGISTER
         and #$ffcf
-        sta $e1c068
+        sta >STATE_REGISTER
         lda backupStack
         tcs
         cli