Specify the ldh instruction, don't turn ld into ldh

22 files changed, 210 insertions, 210 deletions

diff --git a/engine/overworld/auto_movement.asm b/engine/overworld/auto_movement.asm
index 5e70ab8c..9a717641 100755
--- a/engine/overworld/auto_movement.asm
+++ b/engine/overworld/auto_movement.asm
@@ -66,7 +66,7 @@ PalletMovementScript_OakMoveLeft:
 	call FillMemory
 	ld [hl], $ff
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	ld de, wNPCMovementDirections2
 	call MoveSprite
 	ld a, $1
@@ -91,7 +91,7 @@ PalletMovementScript_PlayerMoveLeft:
 	ret nz ; return if Oak is still moving
 	ld a, [wNumStepsToTake]
 	ld [wSimulatedJoypadStatesIndex], a
-	ld [hNPCMovementDirections2Index], a
+	ldh [hNPCMovementDirections2Index], a
 	predef ConvertNPCMovementDirectionsToJoypadMasks
 	call StartSimulatingJoypadStates
 	ld a, $2
@@ -282,7 +282,7 @@ FreezeEnemyTrainerSprite::
 	jr .loop
 .notRival
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	jp SetSpriteMovementBytesToFF
 
 RivalIDs:
diff --git a/engine/overworld/clear_variables.asm b/engine/overworld/clear_variables.asm
index 9b735495..bbb7c986 100644
--- a/engine/overworld/clear_variables.asm
+++ b/engine/overworld/clear_variables.asm
@@ -1,14 +1,14 @@
 ClearVariablesOnEnterMap::
 	ld a, SCREEN_HEIGHT_PX
-	ld [hWY], a
-	ld [rWY], a
+	ldh [hWY], a
+	ldh [rWY], a
 	xor a
-	ld [hAutoBGTransferEnabled], a
+	ldh [hAutoBGTransferEnabled], a
 	ld [wStepCounter], a
 	ld [wLoneAttackNo], a
-	ld [hJoyPressed], a
-	ld [hJoyReleased], a
-	ld [hJoyHeld], a
+	ldh [hJoyPressed], a
+	ldh [hJoyReleased], a
+	ldh [hJoyHeld], a
 	ld [wActionResultOrTookBattleTurn], a
 	ld [wUnusedD5A3], a
 	ld hl, wCardKeyDoorY
diff --git a/engine/overworld/cut.asm b/engine/overworld/cut.asm
index f99bf323..fc5fb578 100755
--- a/engine/overworld/cut.asm
+++ b/engine/overworld/cut.asm
@@ -38,14 +38,14 @@ UsedCut:
 	call ClearSprites
 	call RestoreScreenTilesAndReloadTilePatterns
 	ld a, SCREEN_HEIGHT_PX
-	ld [hWY], a
+	ldh [hWY], a
 	call Delay3
 	call LoadGBPal
 	call LoadCurrentMapView
 	call SaveScreenTilesToBuffer2
 	call Delay3
 	xor a
-	ld [hWY], a
+	ldh [hWY], a
 	ld hl, UsedCutText
 	call PrintText
 	call LoadScreenTilesFromBuffer2
@@ -63,7 +63,7 @@ UsedCut:
 	ld a, SFX_CUT
 	call PlaySound
 	ld a, $90
-	ld [hWY], a
+	ldh [hWY], a
 	call UpdateSprites
 	jp RedrawMapView
 
@@ -75,7 +75,7 @@ InitCutAnimOAM:
 	xor a
 	ld [wWhichAnimationOffsets], a
 	ld a, %11100100
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	ld a, [wCutTile]
 	cp $52
 	jr z, .grass
diff --git a/engine/overworld/cut2.asm b/engine/overworld/cut2.asm
index f16fed66..3d4a5905 100755
--- a/engine/overworld/cut2.asm
+++ b/engine/overworld/cut2.asm
@@ -15,9 +15,9 @@ AnimCut:
 	ld [wCoordAdjustmentAmount], a
 	ld c, 2
 	call AdjustOAMBlockXPos2
-	ld a, [rOBP1]
+	ldh a, [rOBP1]
 	xor $64
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	call DelayFrame
 	pop bc
 	dec c
@@ -65,9 +65,9 @@ AnimCutGrass_UpdateOAMEntries:
 	ld [wCoordAdjustmentAmount], a
 	ld c, 1
 	call AdjustOAMBlockXPos2
-	ld a, [rOBP1]
+	ldh a, [rOBP1]
 	xor $64
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	call DelayFrame
 	pop bc
 	dec c
diff --git a/engine/overworld/dust_smoke.asm b/engine/overworld/dust_smoke.asm
index 2dc6882e..3d87e25a 100755
--- a/engine/overworld/dust_smoke.asm
+++ b/engine/overworld/dust_smoke.asm
@@ -6,7 +6,7 @@ AnimateBoulderDust:
 	ld a, $ff
 	ld [wUpdateSpritesEnabled], a
 	ld a, %11100100
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	call LoadSmokeTileFourTimes
 	callba WriteCutOrBoulderDustAnimationOAMBlock
 	ld c, 8 ; number of steps in animation
@@ -18,9 +18,9 @@ AnimateBoulderDust:
 	ld c, 4
 	jp hl
 .returnAddress
-	ld a, [rOBP1]
+	ldh a, [rOBP1]
 	xor %01100100
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	call Delay3
 	pop bc
 	dec c
diff --git a/engine/overworld/elevator.asm b/engine/overworld/elevator.asm
index 05ca08c9..7a6aca85 100755
--- a/engine/overworld/elevator.asm
+++ b/engine/overworld/elevator.asm
@@ -6,7 +6,7 @@ ShakeElevator::
 	call Delay3
 	ld a, SFX_STOP_ALL_MUSIC
 	call PlaySound
-	ld a, [hSCY]
+	ldh a, [hSCY]
 	ld d, a
 	ld e, $1
 	ld b, 100
@@ -15,7 +15,7 @@ ShakeElevator::
 	xor $fe
 	ld e, a
 	add d
-	ld [hSCY], a
+	ldh [hSCY], a
 	push bc
 	ld c, BANK(SFX_Collision_1)
 	ld a, SFX_COLLISION
@@ -26,7 +26,7 @@ ShakeElevator::
 	dec b
 	jr nz, .shakeLoop
 	ld a, d
-	ld [hSCY], a
+	ldh [hSCY], a
 	ld a, SFX_STOP_ALL_MUSIC
 	call PlaySound
 	ld c, BANK(SFX_Safari_Zone_PA)
diff --git a/engine/overworld/healing_machine.asm b/engine/overworld/healing_machine.asm
index a09a7590..062ef7ea 100755
--- a/engine/overworld/healing_machine.asm
+++ b/engine/overworld/healing_machine.asm
@@ -8,10 +8,10 @@ AnimateHealingMachine:
 	push af
 	ld [hl], $ff
 	push hl
-	ld a, [rOBP1]
+	ldh a, [rOBP1]
 	push af
 	ld a, $e0
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	ld hl, wOAMBuffer + $84
 	ld de, PokeCenterOAMData
 	call CopyHealingMachineOAM
@@ -56,7 +56,7 @@ AnimateHealingMachine:
 	ld c, 32
 	call DelayFrames
 	pop af
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	pop hl
 	pop af
 	ld [hl], a
@@ -78,9 +78,9 @@ PokeCenterOAMData:
 FlashSprite8Times:
 	ld b, 8
 .loop
-	ld a, [rOBP1]
+	ldh a, [rOBP1]
 	xor d
-	ld [rOBP1], a
+	ldh [rOBP1], a
 	ld c, 10
 	call DelayFrames
 	dec b
diff --git a/engine/overworld/hidden_objects.asm b/engine/overworld/hidden_objects.asm
index 5ce7f3cb..855328e7 100755
--- a/engine/overworld/hidden_objects.asm
+++ b/engine/overworld/hidden_objects.asm
@@ -58,7 +58,7 @@ CheckForHiddenObject::
 	ld [wHiddenObjectX], a
 	ld c, a
 	call CheckIfCoordsInFrontOfPlayerMatch
-	ld a, [hCoordsInFrontOfPlayerMatch]
+	ldh a, [hCoordsInFrontOfPlayerMatch]
 	and a
 	jr z, .foundMatchingObject
 	inc hl
@@ -81,7 +81,7 @@ CheckForHiddenObject::
 	ret
 .noMatch
 	ld a, $ff
-	ld [hDidntFindAnyHiddenObject], a
+	ldh [hDidntFindAnyHiddenObject], a
 	ret
 
 ; checks if the coordinates in front of the player's sprite match Y in b and X in c
@@ -127,7 +127,7 @@ CheckIfCoordsInFrontOfPlayerMatch:
 .didNotMatch
 	ld a, $ff
 .done
-	ld [hCoordsInFrontOfPlayerMatch], a
+	ldh [hCoordsInFrontOfPlayerMatch], a
 	ret
 
 INCLUDE "data/events/hidden_objects.asm"
diff --git a/engine/overworld/ledges.asm b/engine/overworld/ledges.asm
index 0f135fb6..cba544f6 100755
--- a/engine/overworld/ledges.asm
+++ b/engine/overworld/ledges.asm
@@ -36,7 +36,7 @@ HandleLedges::
 	inc hl
 	jr .loop
 .foundMatch
-	ld a, [hJoyHeld]
+	ldh a, [hJoyHeld]
 	and e
 	ret z
 	ld a, $ff
diff --git a/engine/overworld/map_sprites.asm b/engine/overworld/map_sprites.asm
index 0de1befd..26a8f1bb 100755
--- a/engine/overworld/map_sprites.asm
+++ b/engine/overworld/map_sprites.asm
@@ -39,7 +39,7 @@ LoadMapSpriteTilePatterns:
 	ld b, $10 ; number of sprite slots
 	ld hl, wSpritePlayerStateData2PictureID
 	xor a
-	ld [hFourTileSpriteCount], a
+	ldh [hFourTileSpriteCount], a
 .copyPictureIDLoop ; loop to copy picture ID from $C2XD to $C2XE
 	ld a, [hli] ; $C2XD (sprite picture ID)
 	ld [hld], a ; $C2XE
@@ -98,14 +98,14 @@ LoadMapSpriteTilePatterns:
 	cp SPRITE_BALL ; is it a 4-tile sprite?
 	jr c, .notFourTileSprite
 	pop af
-	ld a, [hFourTileSpriteCount]
+	ldh a, [hFourTileSpriteCount]
 	add 11
 	jr .storeVRAMSlot
 .notFourTileSprite
 	pop af
 .storeVRAMSlot
 	ld [hl], a ; store VRAM slot at $C2XE
-	ld [hVRAMSlot], a ; used to determine if it's 4-tile sprite later
+	ldh [hVRAMSlot], a ; used to determine if it's 4-tile sprite later
 	ld a, b ; a = current sprite picture ID
 	dec a
 	add a
@@ -128,7 +128,7 @@ LoadMapSpriteTilePatterns:
 	push bc
 	ld hl, vNPCSprites ; VRAM base address
 	ld bc, $c0 ; number of bytes per VRAM slot
-	ld a, [hVRAMSlot]
+	ldh a, [hVRAMSlot]
 	cp 11 ; is it a 4-tile sprite?
 	jr nc, .fourTileSpriteVRAMAddr
 	ld d, a
@@ -141,13 +141,13 @@ LoadMapSpriteTilePatterns:
 	jr .loadStillTilePattern
 .fourTileSpriteVRAMAddr
 	ld hl, vSprites + $7c0 ; address for second 4-tile sprite
-	ld a, [hFourTileSpriteCount]
+	ldh a, [hFourTileSpriteCount]
 	and a
 	jr nz, .loadStillTilePattern
 ; if it's the first 4-tile sprite
 	ld hl, vSprites + $780 ; address for first 4-tile sprite
 	inc a
-	ld [hFourTileSpriteCount], a
+	ldh [hFourTileSpriteCount], a
 .loadStillTilePattern
 	pop bc
 	pop de
@@ -167,7 +167,7 @@ LoadMapSpriteTilePatterns:
 .skipFirstLoad
 	pop de
 	pop hl
-	ld a, [hVRAMSlot]
+	ldh a, [hVRAMSlot]
 	cp 11 ; is it a 4-tile sprite?
 	jr nc, .skipSecondLoad ; if so, there is no second block
 	push de
diff --git a/engine/overworld/missable_objects.asm b/engine/overworld/missable_objects.asm
index 1ebe8064..fd2fe578 100644
--- a/engine/overworld/missable_objects.asm
+++ b/engine/overworld/missable_objects.asm
@@ -31,19 +31,19 @@ LoadMissableObjects:
 	sub d
 	ld h, a
 	ld a, h
-	ld [hDividend], a
+	ldh [hDividend], a
 	ld a, l
-	ld [hDividend+1], a
+	ldh [hDividend+1], a
 	xor a
-	ld [hDividend+2], a
-	ld [hDividend+3], a
+	ldh [hDividend+2], a
+	ldh [hDividend+3], a
 	ld a, $3
-	ld [hDivisor], a
+	ldh [hDivisor], a
 	ld b, $2
 	call Divide                ; divide difference by 3, resulting in the global offset (number of missable items before ours)
 	ld a, [wCurMap]
 	ld b, a
-	ld a, [hDividend+3]
+	ldh a, [hDividend+3]
 	ld c, a                    ; store global offset in c
 	ld de, wMissableObjectList
 	pop hl
@@ -99,7 +99,7 @@ InitializeMissableObjectsFlags:
 
 ; tests if current sprite is a missable object that is hidden/has been removed
 IsObjectHidden:
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	swap a
 	ld b, a
 	ld hl, wMissableObjectList
@@ -120,7 +120,7 @@ IsObjectHidden:
 .notHidden
 	xor a
 .hidden
-	ld [hIsHiddenMissableObject], a
+	ldh [hIsHiddenMissableObject], a
 	ret
 
 ; adds missable object (items, leg. pokemon, etc.) to the map
diff --git a/engine/overworld/movement.asm b/engine/overworld/movement.asm
index d27ccb4b..ac7e1b46 100644
--- a/engine/overworld/movement.asm
+++ b/engine/overworld/movement.asm
@@ -14,7 +14,7 @@ UpdatePlayerSprite:
 ; the maximum number for map tiles
 .checkIfTextBoxInFrontOfSprite
 	aCoord 8, 9
-	ld [hTilePlayerStandingOn], a
+	ldh [hTilePlayerStandingOn], a
 	cp MAP_TILESET_SIZE
 	jr c, .lowerLeftTileIsMapTile
 .disableSprite
@@ -63,7 +63,7 @@ UpdatePlayerSprite:
 	ld a, [wd736]
 	bit 7, a ; is the player sprite spinning due to a spin tile?
 	jr nz, .skipSpriteAnim
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $7
 	ld l, a
 	ld a, [hl]
@@ -89,7 +89,7 @@ UpdatePlayerSprite:
 ; lower priority than the background so that it's partially obscured by the
 ; grass. Only the lower half of the sprite is permitted to have the priority
 ; bit set by later logic.
-	ld a, [hTilePlayerStandingOn]
+	ldh a, [hTilePlayerStandingOn]
 	ld c, a
 	ld a, [wGrassTile]
 	cp c
@@ -103,7 +103,7 @@ UpdatePlayerSprite:
 UnusedReadSpriteDataFunction:
 	push bc
 	push af
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	ld c, a
 	pop af
 	add c
@@ -112,7 +112,7 @@ UnusedReadSpriteDataFunction:
 	ret
 
 UpdateNPCSprite:
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	swap a
 	dec a
 	add a
@@ -122,7 +122,7 @@ UpdateNPCSprite:
 	ld a, [hl]        ; read movement byte 2
 	ld [wCurSpriteMovement2], a
 	ld h, $c1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	ld l, a
 	inc l
 	ld a, [hl]        ; c1x1
@@ -131,7 +131,7 @@ UpdateNPCSprite:
 	call CheckSpriteAvailability
 	ret c             ; if sprite is invisible, on tile >=MAP_TILESET_SIZE, in grass or player is currently walking
 	ld h, $c1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	ld l, a
 	inc l
 	ld a, [hl]        ; c1x1
@@ -151,7 +151,7 @@ UpdateNPCSprite:
 	ret nz           ; don't do anything yet if player is currently moving (redundant, already tested in CheckSpriteAvailability)
 	call InitializeSpriteScreenPosition
 	ld h, $c2
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $6
 	ld l, a
 	ld a, [hl]       ; c2x6: movement byte 1
@@ -264,11 +264,11 @@ ChangeFacingDirection:
 TryWalking:
 	push hl
 	ld h, $c1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $9
 	ld l, a
 	ld [hl], c          ; c1x9 (update facing direction)
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $3
 	ld l, a
 	ld [hl], d          ; c1x3 (update Y movement delta)
@@ -282,7 +282,7 @@ TryWalking:
 	pop de
 	ret c               ; cannot walk there (reinitialization of delay values already done)
 	ld h, $c2
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $4
 	ld l, a
 	ld a, [hl]          ; c2x4: Y position
@@ -291,7 +291,7 @@ TryWalking:
 	ld a, [hl]          ; c2x5: X position
 	add e
 	ld [hl], a          ; update X position
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	ld l, a
 	ld [hl], $10        ; c2x0=16: walk animation counter
 	dec h
@@ -301,7 +301,7 @@ TryWalking:
 
 ; update the walking animation parameters for a sprite that is currently walking
 UpdateSpriteInWalkingAnimation:
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $7
 	ld l, a
 	ld a, [hl]                       ; c1x7 (counter until next walk animation frame)
@@ -317,7 +317,7 @@ UpdateSpriteInWalkingAnimation:
 	and $3
 	ld [hl], a                       ; advance to next animation frame every 4 ticks (16 ticks total for one step)
 .noNextAnimationFrame
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $3
 	ld l, a
 	ld a, [hli]                      ; c1x3 (movement Y delta)
@@ -330,7 +330,7 @@ UpdateSpriteInWalkingAnimation:
 	ld a, [hl]                       ; c1x6 (screen X position)
 	add b
 	ld [hl], a                       ; update screen X position
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	ld l, a
 	inc h
 	ld a, [hl]                       ; c2x0 (walk animation counter)
@@ -343,7 +343,7 @@ UpdateSpriteInWalkingAnimation:
 	ld a, [hl]                       ; c2x6 (movement byte 1)
 	cp $fe
 	jr nc, .initNextMovementCounter  ; values $fe and $ff
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	inc a
 	ld l, a
 	dec h
@@ -351,14 +351,14 @@ UpdateSpriteInWalkingAnimation:
 	ret
 .initNextMovementCounter
 	call Random
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $8
 	ld l, a
-	ld a, [hRandomAdd]
+	ldh a, [hRandomAdd]
 	and $7f
 	ld [hl], a                       ; c2x8: set next movement delay to a random value in [0,$7f]
 	dec h                            ;       note that value 0 actually makes the delay $100 (bug?)
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	inc a
 	ld l, a
 	ld [hl], $2                      ; c1x1 = 2 (movement status)
@@ -375,7 +375,7 @@ UpdateSpriteInWalkingAnimation:
 ; update delay value (c2x8) for sprites in the delayed state (c1x1)
 UpdateSpriteMovementDelay:
 	ld h, $c2
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $6
 	ld l, a
 	ld a, [hl]              ; c2x6: movement byte 1
@@ -390,13 +390,13 @@ UpdateSpriteMovementDelay:
 	jr nz, notYetMoving
 .moving
 	dec h
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	inc a
 	ld l, a
 	ld [hl], $1             ; c1x1 = 1 (mark as ready to move)
 notYetMoving:
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData1AnimFrameCounter - wSpritePlayerStateData1
 	ld l, a
 	ld [hl], $0             ; c1x8 = 0 (walk animation frame)
@@ -429,7 +429,7 @@ MakeNPCFacePlayer:
 .notFacingRight
 	ld c, SPRITE_FACING_LEFT
 .facingDirectionDetermined
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $9
 	ld l, a
 	ld [hl], c              ; c1x9: set facing direction
@@ -440,7 +440,7 @@ InitializeSpriteStatus:
 	inc l
 	ld [hl], $ff  ; $c1x2: set sprite image to $ff (invisible/off screen)
 	inc h
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $2
 	ld l, a
 	ld a, $8
@@ -451,7 +451,7 @@ InitializeSpriteStatus:
 ; calculates the sprite's screen position form its map position and the player position
 InitializeSpriteScreenPosition:
 	ld h, wSpriteStateData2 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData2MapY - wSpritePlayerStateData2
 	ld l, a
 	ld a, [wYCoord]
@@ -475,17 +475,17 @@ InitializeSpriteScreenPosition:
 ; tests if sprite is off screen or otherwise unable to do anything
 CheckSpriteAvailability:
 	predef IsObjectHidden
-	ld a, [hIsHiddenMissableObject]
+	ldh a, [hIsHiddenMissableObject]
 	and a
 	jp nz, .spriteInvisible
 	ld h, wSpriteStateData2 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData2MovementByte1 - wSpritePlayerStateData2
 	ld l, a
 	ld a, [hl]      ; c2x6: movement byte 1
 	cp $fe
 	jr c, .skipXVisibilityTest ; movement byte 1 < $fe (i.e. the sprite's movement is scripted)
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData2MapY - wSpritePlayerStateData2
 	ld l, a
 	ld b, [hl]      ; c2x4: Y pos (+4)
@@ -527,7 +527,7 @@ CheckSpriteAvailability:
 	jr c, .spriteVisible    ; standing on tile with ID >=MAP_TILESET_SIZE (top right tile)
 .spriteInvisible
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData1ImageIndex - wSpritePlayerStateData1
 	ld l, a
 	ld [hl], $ff       ; c1x2
@@ -540,7 +540,7 @@ CheckSpriteAvailability:
 	jr nz, .done           ; if player is currently walking, we're done
 	call UpdateSpriteImage
 	inc h
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $7
 	ld l, a
 	ld a, [wGrassTile]
@@ -556,7 +556,7 @@ CheckSpriteAvailability:
 
 UpdateSpriteImage:
 	ld h, $c1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $8
 	ld l, a
 	ld a, [hli]        ; c1x8: walk animation frame
@@ -564,10 +564,10 @@ UpdateSpriteImage:
 	ld a, [hl]         ; c1x9: facing direction
 	add b
 	ld b, a
-	ld a, [hTilePlayerStandingOn]
+	ldh a, [hTilePlayerStandingOn]
 	add b
 	ld b, a
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $2
 	ld l, a
 	ld [hl], b         ; c1x2: sprite to display
@@ -581,7 +581,7 @@ UpdateSpriteImage:
 ; set carry on failure, clears carry on success
 CanWalkOntoTile:
 	ld h, wSpriteStateData2 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData2MovementByte1 - wSpritePlayerStateData2
 	ld l, a
 	ld a, [hl]         ; c2x6 (movement byte 1)
@@ -602,14 +602,14 @@ CanWalkOntoTile:
 	cp c
 	jr nz, .tilePassableLoop
 	ld h, $c2
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $6
 	ld l, a
 	ld a, [hl]         ; $c2x6 (movement byte 1)
 	inc a
 	jr z, .impassable  ; if $ff, no movement allowed (however, changing direction is)
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld l, a
 	ld a, [hli]        ; c1x4 (screen Y pos)
@@ -628,14 +628,14 @@ CanWalkOntoTile:
 	pop bc
 	pop de
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $c
 	ld l, a
 	ld a, [hl]         ; c1xc (directions in which sprite collision would occur)
 	and b              ; check against chosen direction (1,2,4 or 8)
 	jr nz, .impassable ; collision between sprites, don't go there
 	ld h, wSpriteStateData2 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData2YDisplacement - wSpritePlayerStateData2
 	ld l, a
 	ld a, [hli]        ; c2x2 (sprite Y displacement, initialized at $8, keep track of where a sprite did go)
@@ -666,7 +666,7 @@ CanWalkOntoTile:
 	ret
 .impassable
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	inc a
 	ld l, a
 	ld [hl], $2        ; c1x1 = 2 (set movement status to delayed)
@@ -677,11 +677,11 @@ CanWalkOntoTile:
 	inc l
 	ld [hl], a         ; c1x5 = 0 (clear X movement delta)
 	inc h
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $8
 	ld l, a
 	call Random
-	ld a, [hRandomAdd]
+	ldh a, [hRandomAdd]
 	and $7f
 	ld [hl], a         ; c2x8: set next movement delay to a random value in [0,$7f] (again with delay $100 if value is 0)
 	scf                ; set carry (marking failure to walk)
@@ -692,7 +692,7 @@ CanWalkOntoTile:
 ; hl: output pointer
 GetTileSpriteStandsOn:
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld l, a
 	ld a, [hli]     ; c1x4: screen Y position
@@ -784,7 +784,7 @@ DoScriptedNPCMovement:
 	ld a, [hl]
 	add b
 	ld [hl], a
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $9
 	ld l, a
 	ld a, c
@@ -817,7 +817,7 @@ GetSpriteScreenXPointer:
 
 GetSpriteScreenXYPointerCommon:
 	ld hl, wSpriteStateData1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add l
 	add b
 	ld l, a
@@ -825,7 +825,7 @@ GetSpriteScreenXYPointerCommon:
 
 AnimScriptedNPCMovement:
 	ld hl, wSpriteStateData2
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData2ImageBaseOffset - wSpritePlayerStateData2
 	ld l, a
 	ld a, [hl] ; VRAM slot
@@ -833,7 +833,7 @@ AnimScriptedNPCMovement:
 	swap a
 	ld b, a
 	ld hl, wSpriteStateData1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData1FacingDirection - wSpritePlayerStateData1
 	ld l, a
 	ld a, [hl] ; facing direction
@@ -849,21 +849,21 @@ AnimScriptedNPCMovement:
 .anim
 	add b
 	ld b, a
-	ld [hSpriteVRAMSlotAndFacing], a
+	ldh [hSpriteVRAMSlotAndFacing], a
 	call AdvanceScriptedNPCAnimFrameCounter
 	ld hl, wSpriteStateData1
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpritePlayerStateData1ImageIndex - wSpritePlayerStateData1
 	ld l, a
-	ld a, [hSpriteVRAMSlotAndFacing]
+	ldh a, [hSpriteVRAMSlotAndFacing]
 	ld b, a
-	ld a, [hSpriteAnimFrameCounter]
+	ldh a, [hSpriteAnimFrameCounter]
 	add b
 	ld [hl], a
 	ret
 
 AdvanceScriptedNPCAnimFrameCounter:
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $7
 	ld l, a
 	ld a, [hl] ; intra-animation frame counter
@@ -878,5 +878,5 @@ AdvanceScriptedNPCAnimFrameCounter:
 	inc a
 	and $3
 	ld [hl], a
-	ld [hSpriteAnimFrameCounter], a
+	ldh [hSpriteAnimFrameCounter], a
 	ret
diff --git a/engine/overworld/pathfinding.asm b/engine/overworld/pathfinding.asm
index 7251759c..54cb86b9 100644
--- a/engine/overworld/pathfinding.asm
+++ b/engine/overworld/pathfinding.asm
@@ -8,29 +8,29 @@ FindPathToPlayer:
 	ld hl, wNPCMovementDirections2
 	ld de, $0
 .loop
-	ld a, [hFindPathYProgress]
+	ldh a, [hFindPathYProgress]
 	ld b, a
-	ld a, [hNPCPlayerYDistance] ; Y distance in steps
+	ldh a, [hNPCPlayerYDistance] ; Y distance in steps
 	call CalcDifference
 	ld d, a
 	and a
 	jr nz, .asm_f8da
-	ld a, [hFindPathFlags]
+	ldh a, [hFindPathFlags]
 	set 0, a ; current end of path matches the player's Y coordinate
-	ld [hFindPathFlags], a
+	ldh [hFindPathFlags], a
 .asm_f8da
-	ld a, [hFindPathXProgress]
+	ldh a, [hFindPathXProgress]
 	ld b, a
-	ld a, [hNPCPlayerXDistance] ; X distance in steps
+	ldh a, [hNPCPlayerXDistance] ; X distance in steps
 	call CalcDifference
 	ld e, a
 	and a
 	jr nz, .asm_f8ec
-	ld a, [hFindPathFlags]
+	ldh a, [hFindPathFlags]
 	set 1, a ; current end of path matches the player's X coordinate
-	ld [hFindPathFlags], a
+	ldh [hFindPathFlags], a
 .asm_f8ec
-	ld a, [hFindPathFlags]
+	ldh a, [hFindPathFlags]
 	cp $3 ; has the end of the path reached the player's position?
 	jr z, .done
 ; Compare whether the X distance between the player and the current of the path
@@ -39,7 +39,7 @@ FindPathToPlayer:
 	cp d
 	jr c, .yDistanceGreater
 ; x distance is greater
-	ld a, [hNPCPlayerRelativePosFlags]
+	ldh a, [hNPCPlayerRelativePosFlags]
 	bit 1, a
 	jr nz, .playerIsLeftOfNPC
 	ld d, NPC_MOVEMENT_RIGHT
@@ -47,12 +47,12 @@ FindPathToPlayer:
 .playerIsLeftOfNPC
 	ld d, NPC_MOVEMENT_LEFT
 .next1
-	ld a, [hFindPathXProgress]
+	ldh a, [hFindPathXProgress]
 	add 1
-	ld [hFindPathXProgress], a
+	ldh [hFindPathXProgress], a
 	jr .storeDirection
 .yDistanceGreater
-	ld a, [hNPCPlayerRelativePosFlags]
+	ldh a, [hNPCPlayerRelativePosFlags]
 	bit 0, a
 	jr nz, .playerIsAboveNPC
 	ld d, NPC_MOVEMENT_DOWN
@@ -60,15 +60,15 @@ FindPathToPlayer:
 .playerIsAboveNPC
 	ld d, NPC_MOVEMENT_UP
 .next2
-	ld a, [hFindPathYProgress]
+	ldh a, [hFindPathYProgress]
 	add 1
-	ld [hFindPathYProgress], a
+	ldh [hFindPathYProgress], a
 .storeDirection
 	ld a, d
 	ld [hli], a
-	ld a, [hFindPathNumSteps]
+	ldh a, [hFindPathNumSteps]
 	inc a
-	ld [hFindPathNumSteps], a
+	ldh [hFindPathNumSteps], a
 	jp .loop
 .done
 	ld [hl], $ff
@@ -76,13 +76,13 @@ FindPathToPlayer:
 
 CalcPositionOfPlayerRelativeToNPC:
 	xor a
-	ld [hNPCPlayerRelativePosFlags], a
+	ldh [hNPCPlayerRelativePosFlags], a
 	ld a, [wSpritePlayerStateData1YPixels]
 	ld d, a
 	ld a, [wSpritePlayerStateData1XPixels]
 	ld e, a
 	ld hl, wSpriteStateData1
-	ld a, [hNPCSpriteOffset]
+	ldh a, [hNPCSpriteOffset]
 	add l
 	add wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld l, a
@@ -115,7 +115,7 @@ CalcPositionOfPlayerRelativeToNPC:
 	ld [hli], a
 	call DivideBytes ; divide Y absolute distance by 16
 	ld a, [hl] ; quotient
-	ld [hNPCPlayerYDistance], a
+	ldh [hNPCPlayerYDistance], a
 	pop hl
 	inc hl
 	ld b, e
@@ -136,23 +136,23 @@ CalcPositionOfPlayerRelativeToNPC:
 	res 1, [hl]
 	pop hl
 .divideXDistance
-	ld [hDividend2], a
+	ldh [hDividend2], a
 	ld a, 16
-	ld [hDivisor2], a
+	ldh [hDivisor2], a
 	call DivideBytes ; divide X absolute distance by 16
-	ld a, [hQuotient2]
-	ld [hNPCPlayerXDistance], a
-	ld a, [hNPCPlayerRelativePosPerspective]
+	ldh a, [hQuotient2]
+	ldh [hNPCPlayerXDistance], a
+	ldh a, [hNPCPlayerRelativePosPerspective]
 	and a
 	ret z
-	ld a, [hNPCPlayerRelativePosFlags]
+	ldh a, [hNPCPlayerRelativePosFlags]
 	cpl
 	and $3
-	ld [hNPCPlayerRelativePosFlags], a
+	ldh [hNPCPlayerRelativePosFlags], a
 	ret
 
 ConvertNPCMovementDirectionsToJoypadMasks:
-	ld a, [hNPCMovementDirections2Index]
+	ldh a, [hNPCMovementDirections2Index]
 	ld [wNPCMovementDirections2Index], a
 	dec a
 	ld de, wSimulatedJoypadStatesEnd
@@ -166,9 +166,9 @@ ConvertNPCMovementDirectionsToJoypadMasks:
 	call ConvertNPCMovementDirectionToJoypadMask
 	ld [de], a
 	inc de
-	ld a, [hNPCMovementDirections2Index]
+	ldh a, [hNPCMovementDirections2Index]
 	dec a
-	ld [hNPCMovementDirections2Index], a
+	ldh [hNPCMovementDirections2Index], a
 	jr nz, .loop
 	ret
 
diff --git a/engine/overworld/player_animations.asm b/engine/overworld/player_animations.asm
index cfd6cc8d..fec10daf 100755
--- a/engine/overworld/player_animations.asm
+++ b/engine/overworld/player_animations.asm
@@ -516,9 +516,9 @@ _HandleMidJump::
 	call UpdateSprites
 	call Delay3
 	xor a
-	ld [hJoyHeld], a
-	ld [hJoyPressed], a
-	ld [hJoyReleased], a
+	ldh [hJoyHeld], a
+	ldh [hJoyPressed], a
+	ldh [hJoyReleased], a
 	ld [wPlayerJumpingYScreenCoordsIndex], a
 	ld hl, wd736
 	res 6, [hl] ; not jumping down a ledge any more
diff --git a/engine/overworld/player_state.asm b/engine/overworld/player_state.asm
index 9ff67df8..f2e74683 100644
--- a/engine/overworld/player_state.asm
+++ b/engine/overworld/player_state.asm
@@ -17,7 +17,7 @@ IsPlayerStandingOnWarp::
 	ld a, [hli] ; target warp
 	ld [wDestinationWarpID], a
 	ld a, [hl] ; target map
-	ld [hWarpDestinationMap], a
+	ldh [hWarpDestinationMap], a
 	ld hl, wd736
 	set 2, [hl] ; standing on warp flag
 	ret
@@ -297,7 +297,7 @@ _GetTileAndCoordsInFrontOfPlayer:
 
 GetTileTwoStepsInFrontOfPlayer:
 	xor a
-	ld [hPlayerFacing], a
+	ldh [hPlayerFacing], a
 	ld hl, wYCoord
 	ld a, [hli]
 	ld d, a
@@ -378,33 +378,33 @@ CheckForBoulderCollisionWithSprites:
 	ld hl, wSprite01StateData2MapY
 	add hl, de
 	ld a, [hli] ; map Y position
-	ld [hPlayerYCoord], a
+	ldh [hPlayerYCoord], a
 	ld a, [hl] ; map X position
-	ld [hPlayerXCoord], a
+	ldh [hPlayerXCoord], a
 	ld a, [wNumSprites]
 	ld c, a
 	ld de, $f
 	ld hl, wSprite01StateData2MapY
-	ld a, [hPlayerFacing]
+	ldh a, [hPlayerFacing]
 	and $3 ; facing up or down?
 	jr z, .pushingHorizontallyLoop
 .pushingVerticallyLoop
 	inc hl
-	ld a, [hPlayerXCoord]
+	ldh a, [hPlayerXCoord]
 	cp [hl]
 	jr nz, .nextSprite1 ; if X coordinates don't match
 	dec hl
 	ld a, [hli]
 	ld b, a
-	ld a, [hPlayerFacing]
+	ldh a, [hPlayerFacing]
 	rrca
 	jr c, .pushingDown
 ; pushing up
-	ld a, [hPlayerYCoord]
+	ldh a, [hPlayerYCoord]
 	dec a
 	jr .compareYCoords
 .pushingDown
-	ld a, [hPlayerYCoord]
+	ldh a, [hPlayerYCoord]
 	inc a
 .compareYCoords
 	cp b
@@ -417,19 +417,19 @@ CheckForBoulderCollisionWithSprites:
 .pushingHorizontallyLoop
 	ld a, [hli]
 	ld b, a
-	ld a, [hPlayerYCoord]
+	ldh a, [hPlayerYCoord]
 	cp b
 	jr nz, .nextSprite2
 	ld b, [hl]
-	ld a, [hPlayerFacing]
+	ldh a, [hPlayerFacing]
 	bit 2, a
 	jr nz, .pushingLeft
 ; pushing right
-	ld a, [hPlayerXCoord]
+	ldh a, [hPlayerXCoord]
 	inc a
 	jr .compareXCoords
 .pushingLeft
-	ld a, [hPlayerXCoord]
+	ldh a, [hPlayerXCoord]
 	dec a
 .compareXCoords
 	cp b
diff --git a/engine/overworld/push_boulder.asm b/engine/overworld/push_boulder.asm
index da1c6dee..fb4d06aa 100644
--- a/engine/overworld/push_boulder.asm
+++ b/engine/overworld/push_boulder.asm
@@ -6,15 +6,15 @@ TryPushingBoulder::
 	bit 1, a ; has boulder dust animation from previous push played yet?
 	ret nz
 	xor a
-	ld [hSpriteIndexOrTextID], a
+	ldh [hSpriteIndexOrTextID], a
 	call IsSpriteInFrontOfPlayer
-	ld a, [hSpriteIndexOrTextID]
+	ldh a, [hSpriteIndexOrTextID]
 	ld [wBoulderSpriteIndex], a
 	and a
 	jp z, ResetBoulderPushFlags
 	ld hl, wSpritePlayerStateData1MovementStatus
 	ld d, $0
-	ld a, [hSpriteIndexOrTextID]
+	ldh a, [hSpriteIndexOrTextID]
 	swap a
 	ld e, a
 	add hl, de
@@ -27,14 +27,14 @@ TryPushingBoulder::
 	bit 6, [hl]
 	set 6, [hl] ; indicate that the player has tried pushing
 	ret z ; the player must try pushing twice before the boulder will move
-	ld a, [hJoyHeld]
+	ldh a, [hJoyHeld]
 	and D_RIGHT | D_LEFT | D_UP | D_DOWN
 	ret z
 	predef CheckForCollisionWhenPushingBoulder
 	ld a, [wTileInFrontOfBoulderAndBoulderCollisionResult]
 	and a ; was there a collision?
 	jp nz, ResetBoulderPushFlags
-	ld a, [hJoyHeld]
+	ldh a, [hJoyHeld]
 	ld b, a
 	ld a, [wSpritePlayerStateData1FacingDirection]
 	cp SPRITE_FACING_UP
@@ -92,7 +92,7 @@ DoBoulderDustAnimation::
 	call ResetBoulderPushFlags
 	set 7, [hl]
 	ld a, [wBoulderSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	call GetSpriteMovementByte2Pointer
 	ld [hl], $10
 	ld a, SFX_CUT
diff --git a/engine/overworld/special_warps.asm b/engine/overworld/special_warps.asm
index 042146f9..54471ee0 100644
--- a/engine/overworld/special_warps.asm
+++ b/engine/overworld/special_warps.asm
@@ -34,7 +34,7 @@ LoadSpecialWarpData:
 	cp TRADE_CENTER
 	jr nz, .notTradeCenter
 	ld hl, TradeCenterSpec1
-	ld a, [hSerialConnectionStatus]
+	ldh a, [hSerialConnectionStatus]
 	cp USING_INTERNAL_CLOCK ; which gameboy is clocking determines who is on the left and who is on the right
 	jr z, .copyWarpData
 	ld hl, TradeCenterSpec2
@@ -43,7 +43,7 @@ LoadSpecialWarpData:
 	cp COLOSSEUM
 	jr nz, .notColosseum
 	ld hl, ColosseumSpec1
-	ld a, [hSerialConnectionStatus]
+	ldh a, [hSerialConnectionStatus]
 	cp USING_INTERNAL_CLOCK
 	jr z, .copyWarpData
 	ld hl, ColosseumSpec2
diff --git a/engine/overworld/sprite_collisions.asm b/engine/overworld/sprite_collisions.asm
index 48cd95b9..e6c415ab 100644
--- a/engine/overworld/sprite_collisions.asm
+++ b/engine/overworld/sprite_collisions.asm
@@ -6,7 +6,7 @@ _UpdateSprites::
 	ld l, a
 	sub wSpritePlayerStateData2ImageBaseOffset - wSpritePlayerStateData2
 	ld c, a
-	ld [hCurrentSpriteOffset], a
+	ldh [hCurrentSpriteOffset], a
 	ld a, [hl]
 	and a
 	jr z, .skipSprite   ; tests $c2Xe
@@ -31,10 +31,10 @@ _UpdateSprites::
 UpdateNonPlayerSprite:
 	dec a
 	swap a
-	ld [hTilePlayerStandingOn], a  ; $10 * sprite#
+	ldh [hTilePlayerStandingOn], a  ; $10 * sprite#
 	ld a, [wNPCMovementScriptSpriteOffset] ; some sprite offset?
 	ld b, a
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	cp b
 	jr nz, .unequal
 	jp DoScriptedNPCMovement
@@ -54,7 +54,7 @@ DetectCollisionBetweenSprites:
 	nop
 
 	ld h, wSpriteStateData1 / $100
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add wSpriteStateData1 % $100
 	ld l, a
 
@@ -79,7 +79,7 @@ DetectCollisionBetweenSprites:
 	and $f0
 	or c
 
-	ld [hFF90], a ; store Y coordinate adjusted for direction of movement
+	ldh [hFF90], a ; store Y coordinate adjusted for direction of movement
 
 	ld a, [hli] ; a = [$c1i5] (delta X) (-1, 0, or 1)
 	call SetSpriteCollisionValues
@@ -92,7 +92,7 @@ DetectCollisionBetweenSprites:
 	and $f0
 	or c
 
-	ld [hFF91], a ; store X coordinate adjusted for direction of movement
+	ldh [hFF91], a ; store X coordinate adjusted for direction of movement
 
 	ld a, l
 	add 7
@@ -102,18 +102,18 @@ DetectCollisionBetweenSprites:
 	ld [hld], a ; zero [$c1id] XXX what's [$c1id] for?
 	ld [hld], a ; zero [$c1ic] (directions in which collisions occurred)
 
-	ld a, [hFF91]
+	ldh a, [hFF91]
 	ld [hld], a ; [$c1ib] = adjusted X coordinate
-	ld a, [hFF90]
+	ldh a, [hFF90]
 	ld [hl], a ; [$c1ia] = adjusted Y coordinate
 
 	xor a ; zero the loop counter
 
 .loop
-	ld [hFF8F], a ; store loop counter
+	ldh [hFF8F], a ; store loop counter
 	swap a
 	ld e, a
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	cp e ; does the loop sprite match the current sprite?
 	jp z, .next ; go to the next sprite if they match
 
@@ -128,7 +128,7 @@ DetectCollisionBetweenSprites:
 	inc a
 	jp z, .next ; go the next sprite if offscreen
 
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add 10
 	ld l, a
 
@@ -154,7 +154,7 @@ DetectCollisionBetweenSprites:
 	cpl
 	inc a
 .noCarry1
-	ld [hFF90], a ; store the distance between the two sprites' adjusted Y values
+	ldh [hFF90], a ; store the distance between the two sprites' adjusted Y values
 
 ; Use the carry flag set by the above subtraction to determine which sprite's
 ; Y coordinate is larger. This information is used later to set [$c1ic],
@@ -176,11 +176,11 @@ DetectCollisionBetweenSprites:
 	ld b, 9
 
 .next1
-	ld a, [hFF90] ; a = distance between adjusted Y coordinates
+	ldh a, [hFF90] ; a = distance between adjusted Y coordinates
 	sub b
-	ld [hFF92], a ; store distance adjusted using sprite i's direction
+	ldh [hFF92], a ; store distance adjusted using sprite i's direction
 	ld a, b
-	ld [hFF90], a ; store 7 or 9 depending on sprite i's delta Y
+	ldh [hFF90], a ; store 7 or 9 depending on sprite i's delta Y
 	jr c, .checkXDistance
 
 ; If sprite j's delta Y is 0, then b = 7, else b = 9.
@@ -193,7 +193,7 @@ DetectCollisionBetweenSprites:
 	ld b, 9
 
 .next2
-	ld a, [hFF92] ; a = distance adjusted using sprite i's direction
+	ldh a, [hFF92] ; a = distance adjusted using sprite i's direction
 	sub b ; adjust distance using sprite j's direction
 	jr z, .checkXDistance
 	jr nc, .next ; go to next sprite if distance is still positive after both adjustments
@@ -225,7 +225,7 @@ DetectCollisionBetweenSprites:
 	cpl
 	inc a
 .noCarry2
-	ld [hFF91], a ; store the distance between the two sprites' adjusted X values
+	ldh [hFF91], a ; store the distance between the two sprites' adjusted X values
 
 ; Use the carry flag set by the above subtraction to determine which sprite's
 ; X coordinate is larger. This information is used later to set [$c1ic],
@@ -247,11 +247,11 @@ DetectCollisionBetweenSprites:
 	ld b, 9
 
 .next3
-	ld a, [hFF91] ; a = distance between adjusted X coordinates
+	ldh a, [hFF91] ; a = distance between adjusted X coordinates
 	sub b
-	ld [hFF92], a ; store distance adjusted using sprite i's direction
+	ldh [hFF92], a ; store distance adjusted using sprite i's direction
 	ld a, b
-	ld [hFF91], a ; store 7 or 9 depending on sprite i's delta X
+	ldh [hFF91], a ; store 7 or 9 depending on sprite i's delta X
 	jr c, .collision
 
 ; If sprite j's delta X is 0, then b = 7, else b = 9.
@@ -264,15 +264,15 @@ DetectCollisionBetweenSprites:
 	ld b, 9
 
 .next4
-	ld a, [hFF92] ; a = distance adjusted using sprite i's direction
+	ldh a, [hFF92] ; a = distance adjusted using sprite i's direction
 	sub b ; adjust distance using sprite j's direction
 	jr z, .collision
 	jr nc, .next ; go to next sprite if distance is still positive after both adjustments
 
 .collision
-	ld a, [hFF91] ; a = 7 or 9 depending on sprite i's delta X
+	ldh a, [hFF91] ; a = 7 or 9 depending on sprite i's delta X
 	ld b, a
-	ld a, [hFF90] ; a = 7 or 9 depending on sprite i's delta Y
+	ldh a, [hFF90] ; a = 7 or 9 depending on sprite i's delta Y
 	inc l
 
 ; If delta X isn't 0 and delta Y is 0, then b = %0011, else b = %1100.
@@ -294,7 +294,7 @@ DetectCollisionBetweenSprites:
 ; set bit in [$c1ie] or [$c1if] to indicate which sprite the collision occurred with
 	inc l
 	inc l
-	ld a, [hFF8F] ; a = loop counter
+	ldh a, [hFF8F] ; a = loop counter
 	ld de, SpriteCollisionBitTable
 	add a
 	add e
@@ -311,7 +311,7 @@ DetectCollisionBetweenSprites:
 	ld [hl], a
 
 .next
-	ld a, [hFF8F] ; a = loop counter
+	ldh a, [hFF8F] ; a = loop counter
 	inc a
 	cp $10
 	jp nz, .loop
diff --git a/engine/overworld/tilesets.asm b/engine/overworld/tilesets.asm
index 88147233..f40cbbc2 100644
--- a/engine/overworld/tilesets.asm
+++ b/engine/overworld/tilesets.asm
@@ -23,9 +23,9 @@ LoadTilesetHeader:
 	dec c
 	jr nz, .copyTilesetHeaderLoop
 	ld a, [hl]
-	ld [hTilesetType], a
+	ldh [hTilesetType], a
 	xor a
-	ld [hMovingBGTilesCounter1], a
+	ldh [hMovingBGTilesCounter1], a
 	pop hl
 	ld a, [wCurMapTileset]
 	push hl
@@ -38,7 +38,7 @@ LoadTilesetHeader:
 	jr c, .asm_c797
 	ld a, [wCurMapTileset]
 	ld b, a
-	ld a, [hPreviousTileset]
+	ldh a, [hPreviousTileset]
 	cp b
 	jr z, .done
 .asm_c797
diff --git a/engine/overworld/trainer_sight.asm b/engine/overworld/trainer_sight.asm
index c12c064b..5046f5f6 100755
--- a/engine/overworld/trainer_sight.asm
+++ b/engine/overworld/trainer_sight.asm
@@ -2,26 +2,26 @@ _GetSpritePosition1::
 	ld hl, wSpriteStateData1
 	ld de, wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	call GetSpriteDataPointer
 	ld a, [hli] ; c1x4 (screen Y pos)
-	ld [hSpriteScreenYCoord], a
+	ldh [hSpriteScreenYCoord], a
 	inc hl
 	ld a, [hl] ; c1x6 (screen X pos)
-	ld [hSpriteScreenXCoord], a
+	ldh [hSpriteScreenXCoord], a
 	ld de, wSpritePlayerStateData2MapY - wSpritePlayerStateData1XPixels
 	add hl, de
 	ld a, [hli] ; c2x4 (map Y pos)
-	ld [hSpriteMapYCoord], a
+	ldh [hSpriteMapYCoord], a
 	ld a, [hl] ; c2x5 (map X pos)
-	ld [hSpriteMapXCoord], a
+	ldh [hSpriteMapXCoord], a
 	ret
 
 _GetSpritePosition2::
 	ld hl, wSpriteStateData1
 	ld de, wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	call GetSpriteDataPointer
 	ld a, [hli] ; c1x4 (screen Y pos)
 	ld [wSavedSpriteScreenY], a
@@ -40,18 +40,18 @@ _SetSpritePosition1::
 	ld hl, wSpriteStateData1
 	ld de, wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	call GetSpriteDataPointer
-	ld a, [hSpriteScreenYCoord] ; c1x4 (screen Y pos)
+	ldh a, [hSpriteScreenYCoord] ; c1x4 (screen Y pos)
 	ld [hli], a
 	inc hl
-	ld a, [hSpriteScreenXCoord] ; c1x6 (screen X pos)
+	ldh a, [hSpriteScreenXCoord] ; c1x6 (screen X pos)
 	ld [hl], a
 	ld de, wSpritePlayerStateData2MapY - wSpritePlayerStateData1XPixels
 	add hl, de
-	ld a, [hSpriteMapYCoord] ; c2x4 (map Y pos)
+	ldh a, [hSpriteMapYCoord] ; c2x4 (map Y pos)
 	ld [hli], a
-	ld a, [hSpriteMapXCoord] ; c2x5 (map X pos)
+	ldh a, [hSpriteMapXCoord] ; c2x5 (map X pos)
 	ld [hl], a
 	ret
 
@@ -59,7 +59,7 @@ _SetSpritePosition2::
 	ld hl, wSpriteStateData1
 	ld de, wSpritePlayerStateData1YPixels - wSpritePlayerStateData1
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	call GetSpriteDataPointer
 	ld a, [wSavedSpriteScreenY]
 	ld [hli], a ; c1x4 (screen Y pos)
@@ -144,7 +144,7 @@ TrainerWalkUpToPlayer::
 	call FillMemory     ; write the necessary steps to reach player
 	ld [hl], $ff        ; write end of list sentinel
 	ld a, [wSpriteIndex]
-	ld [hSpriteIndex], a
+	ldh [hSpriteIndex], a
 	jp MoveSprite_
 
 ; input: de = offset within sprite entry
@@ -152,7 +152,7 @@ TrainerWalkUpToPlayer::
 GetSpriteDataPointer:
 	push de
 	add hl, de
-	ld a, [hSpriteIndex]
+	ldh a, [hSpriteIndex]
 	swap a
 	ld d, $0
 	ld e, a
diff --git a/engine/overworld/turn_sprite.asm b/engine/overworld/turn_sprite.asm
index bef26537..4ff58239 100755
--- a/engine/overworld/turn_sprite.asm
+++ b/engine/overworld/turn_sprite.asm
@@ -1,12 +1,12 @@
 UpdateSpriteFacingOffsetAndDelayMovement::
 	ld h, $c2
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $8
 	ld l, a
 	ld a, $7f ; maximum movement delay
 	ld [hl], a ; c2x8 (movement delay)
 	dec h
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $9
 	ld l, a
 	ld a, [hld] ; c1x9 (facing direction)
@@ -14,7 +14,7 @@ UpdateSpriteFacingOffsetAndDelayMovement::
 	xor a
 	ld [hld], a
 	ld [hl], a ; c1x8 (walk animation frame)
-	ld a, [hCurrentSpriteOffset]
+	ldh a, [hCurrentSpriteOffset]
 	add $2
 	ld l, a
 	ld a, [hl] ; c1x2 (facing and animation table offset)
diff --git a/engine/overworld/update_map.asm b/engine/overworld/update_map.asm
index 92ae2b10..53a5592d 100644
--- a/engine/overworld/update_map.asm
+++ b/engine/overworld/update_map.asm
@@ -50,13 +50,13 @@ RedrawMapView:
 	ld a, [wIsInBattle]
 	inc a
 	ret z
-	ld a, [hAutoBGTransferEnabled]
+	ldh a, [hAutoBGTransferEnabled]
 	push af
-	ld a, [hTilesetType]
+	ldh a, [hTilesetType]
 	push af
 	xor a
-	ld [hAutoBGTransferEnabled], a
-	ld [hTilesetType], a ; no flower/water BG tile animations
+	ldh [hAutoBGTransferEnabled], a
+	ldh [hTilesetType], a ; no flower/water BG tile animations
 	call LoadCurrentMapView
 	call RunDefaultPaletteCommand
 	ld hl, wMapViewVRAMPointer
@@ -73,7 +73,7 @@ RedrawMapView:
 	ld a, h
 	ld [wBuffer + 1], a ; this copy of the address is not used
 	ld a, 2
-	ld [hRedrawMapViewRowOffset], a
+	ldh [hRedrawMapViewRowOffset], a
 	ld c, SCREEN_HEIGHT / 2 ; number of rows of 2x2 tiles (this covers the whole screen)
 .redrawRowLoop
 	push bc
@@ -81,7 +81,7 @@ RedrawMapView:
 	push hl
 	ld hl, wTileMap - 2 * SCREEN_WIDTH
 	ld de, SCREEN_WIDTH
-	ld a, [hRedrawMapViewRowOffset]
+	ldh a, [hRedrawMapViewRowOffset]
 .calcWRAMAddrLoop
 	add hl, de
 	dec a
@@ -89,7 +89,7 @@ RedrawMapView:
 	call CopyToRedrawRowOrColumnSrcTiles
 	pop hl
 	ld de, BG_MAP_WIDTH
-	ld a, [hRedrawMapViewRowOffset]
+	ldh a, [hRedrawMapViewRowOffset]
 	ld c, a
 .calcVRAMAddrLoop
 	add hl, de
@@ -98,11 +98,11 @@ RedrawMapView:
 	or $98
 	dec c
 	jr nz, .calcVRAMAddrLoop
-	ld [hRedrawRowOrColumnDest + 1], a
+	ldh [hRedrawRowOrColumnDest + 1], a
 	ld a, l
-	ld [hRedrawRowOrColumnDest], a
+	ldh [hRedrawRowOrColumnDest], a
 	ld a, REDRAW_ROW
-	ld [hRedrawRowOrColumnMode], a
+	ldh [hRedrawRowOrColumnMode], a
 	call DelayFrame
 	ld hl, hRedrawMapViewRowOffset
 	inc [hl]
@@ -112,9 +112,9 @@ RedrawMapView:
 	dec c
 	jr nz, .redrawRowLoop
 	pop af
-	ld [hTilesetType], a
+	ldh [hTilesetType], a
 	pop af
-	ld [hAutoBGTransferEnabled], a
+	ldh [hAutoBGTransferEnabled], a
 	ret
 
 CompareHLWithBC: