Fix black screen, text rendering, and keyboard input issues

main.s

@@ -38,6 +38,7 @@ START:
 
     ; Enable DMA for Copper, Bitplanes, Blitter
     move.w  #$83C0,DMACON(a6) ; Set DMAEN, BPLEN, COPEN, BLTEN
+    move.w  #0,COPJMP1(a6)    ; Strobe Copper to start immediately
 
 MAIN_LOOP:
     ; Wait for vertical blank
@@ -49,25 +50,15 @@ MAIN_LOOP:
     ; 2. Update Game Logic
     bsr     UpdateGame
 
-    ; 3. Check for Exit (Left Mouse Button for now)
+    ; 3. Check for Reset (Left Mouse Button)
     btst    #6,CIAA
     bne.s   MAIN_LOOP
 
-EXIT:
-    ; Restore System
-    lea     CUSTOM,a6
-    move.w  #$7FFF,DMACON(a6)
-    move.w  #$7FFF,INTENA(a6)
-    
-    move.w  OldDmaCon,DMACON(a6)
-    move.w  OldIntEna,INTENA(a6)
+    ; If button pressed, restart game
+    bra     START
 
-    ; Enable multitasking
-    ; move.l  4.w,a6
-    ; jsr     -138(a6)        ; Permit
-
-    moveq   #0,d0
-    rts
+    ; EXIT label removed as we don't return to OS
+    ; The bootblock environment has no OS to return to cleanly in this simple setup
 
 ; ---------------------------------------------------------------------------
 ; Helper Routines
@@ -78,7 +69,7 @@ WaitVBlank:
 .wait:
     move.l  $04(a6),d0
     and.l   #$1ff00,d0
-    cmp.l   #300<<8,d0
+    cmp.l   #250<<8,d0
     bne.s   .wait
     rts