Fix program freeze when lcd is off at boot

When running with no bootrom LCD could be off (could be handled on the emulator too) the program would freeze
alloncm · Dec 25, 2022 · e92bb53 · e92bb53
1 parent bf961a5
commit e92bb53
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/src/color_bg_oam_priority.asm b/src/color_bg_oam_priority.asm
@@ -152,6 +152,9 @@ WaitVblank:
 ; Turn off the LCD display
 ;----------------------------------------------------
 TurnOffLcd:
+    and a, %10000000                                    ; get LCDC bit 7 to check if lcd is off
+    cp a, 0                                             ; check lcdc for lcd off
+    ret z                                               ; if lcd already off return and dont wait for vblank (it will never return)
     call WaitVblank
     ld a, 0
     ld [rLCDC], a