Proper DAS charge holding.

src/include/input.asm

@@ -11,6 +11,7 @@ hAState::      ds 1
 hBState::      ds 1
 hStartState::  ds 1
 hSelectState:: ds 1
+hDASCharge::   ds 1
 
 
 
@@ -25,10 +26,37 @@ InputInit::
     ldh [hBState], a
     ldh [hStartState], a
     ldh [hSelectState], a
+    ldh [hDASCharge], a
     ret
 
 
 GetInput::
+    ; Check if the left state > DAS charge.
+    ldh a, [hLeftState]
+    ld b, a
+    ldh a, [hDASCharge]
+    cp a, b
+    ; If so, save the new DAS charge.
+    jr nc, :+
+    ld a, b
+    ldh [hDASCharge], a
+
+    ; Check if the right state > DAS charge.
+:   ldh a, [hRightState]
+    ld b, a
+    ldh a, [hDASCharge]
+    cp a, b
+    ; If so, save the new DAS charge.
+    jr nc, :+
+    ld a, b
+    ldh [hDASCharge], a
+
+    ; There's an overflow risk here if the DAS charge is 255.
+:   cp a, $FF
+    jr nz, .btns
+    dec a
+    ldh [hDASCharge], a
+
     ; Get the button state.
 .btns
     ld a, P1F_GET_BTN
@@ -39,12 +67,13 @@ GetInput::
     ldh a, [rP1]
     ld b, a
 
+    ; Read A button.
 .readA
-    bit 0, b ; A
+    bit 0, b
     jr nz, .clearA
 .setA
     ldh a, [hAState]
-    cp $FF
+    cp a, $FF
     jr z, .readB
     inc a
     ldh [hAState], a
@@ -53,12 +82,13 @@ GetInput::
     xor a, a
     ldh [hAState], a
 
+    ; Read B button.
 .readB
-    bit 1, b ; B
+    bit 1, b
     jr nz, .clearB
 .setB
     ldh a, [hBState]
-    cp $FF
+    cp a, $FF
     jr z, .readSelect
     inc a
     ldh [hBState], a
@@ -67,12 +97,13 @@ GetInput::
     xor a, a
     ldh [hBState], a
 
+    ; Read select button.
 .readSelect
-    bit 2, b ; Select
+    bit 2, b
     jr nz, .clearSelect
 .setSelect
     ldh a, [hSelectState]
-    cp $FF
+    cp a, $FF
     jr z, .readStart
     inc a
     ldh [hSelectState], a
@@ -81,12 +112,13 @@ GetInput::
     xor a, a
     ldh [hSelectState], a
 
+    ; Read start button.
 .readStart
-    bit 3, b ; Start
+    bit 3, b
     jr nz, .clearStart
 .setStart
     ldh a, [hStartState]
-    cp $FF
+    cp a, $FF
     jr z, .dpad
     inc a
     ldh [hStartState], a
@@ -95,7 +127,6 @@ GetInput::
     xor a, a
     ldh [hStartState], a
 
-
     ; Get the dpad state.
 .dpad
     ld a, P1F_GET_DPAD
@@ -106,12 +137,13 @@ GetInput::
     ldh a, [rP1]
     ld b, a
 
+    ; Read up button.
 .readUp
-    bit 2, b ; Up
+    bit 2, b
     jr nz, .clearUp
 .setUp
     ldh a, [hUpState]
-    cp $FF
+    cp a, $FF
     jr z, .readDown
     inc a
     ldh [hUpState], a
@@ -120,12 +152,13 @@ GetInput::
     xor a, a
     ldh [hUpState], a
 
+    ; Read down button.
 .readDown
-    bit 3, b ; Down
+    bit 3, b
     jr nz, .clearDown
 .setDown
     ldh a, [hDownState]
-    cp $FF
+    cp a, $FF
     jr z, .readLeft
     inc a
     ldh [hDownState], a
@@ -134,33 +167,50 @@ GetInput::
     xor a, a
     ldh [hDownState], a
 
+    ; Read left button. If it's just been pressed, restore the held DAS charge.
 .readLeft
-    bit 1, b ; Left
+    bit 1, b
     jr nz, .clearLeft
 .setLeft
     ldh a, [hLeftState]
-    cp $FF
+    cp a, $FF
     jr z, .readRight
-    inc a
+    cp a, 0
+    jr nz, :+
+    ldh a, [hDASCharge]
+:   inc a
     ldh [hLeftState], a
     jr .readRight
 .clearLeft
     xor a, a
     ldh [hLeftState], a
 
+    ; Read right button. If it's just been pressed, restore the held DAS charge.
 .readRight
-    bit 0, b ; Right
+    bit 0, b
     jr nz, .clearRight
 .setRight
     ldh a, [hRightState]
-    cp $FF
+    cp a, $FF
-    ret z
+    jr z, .checkDAS
-    inc a
+    cp a, 0
+    jr nz, :+
+    ldh a, [hDASCharge]
+:   inc a
     ldh [hRightState], a
-    ret
+    jr .checkDAS
 .clearRight
     xor a, a
     ldh [hRightState], a
+
+    ; If none of the four directions are pressed, reset the DAS charge.
+.checkDAS
+    ld a, b
+    or a, $F0
+    cp a, $FF
+    ret nz
+    xor a, a
+    ldh [hDASCharge], a
     ret
 
 

tools/Emulicious.ini

@@ -1,5 +1,5 @@
 #Emulicious settings file
-#Fri Oct 13 11:30:41 CEST 2023
+#Mon Oct 16 05:45:08 CEST 2023
 WindowEventViewerWindowHeight=861
 WindowEventViewerWindowDivider=309
 WindowMemoryTracerWindowY=631
@@ -125,9 +125,9 @@ Key1=75
 Key0=74
 Gamepad1Key19=-1
 Gamepad1Key18=-1
-WindowEventViewerWindowY=489
+WindowEventViewerWindowY=673
 Gamepad1Key17=-1
-WindowEventViewerWindowX=1472
+WindowEventViewerWindowX=1846
 Gamepad1Key16=-1
 Gamepad1Key15=-1
 Gamepad1Key14=-1
@@ -135,7 +135,7 @@ Gamepad1Key13=-1
 Gamepad1Key12=-1
 Gamepad1Key11=-1
 Gamepad1Key10=-1
-WindowMemoryEditorSelectedAddress=-1
+WindowMemoryEditorSelectedAddress=116
 WindowMemoryEditorWidth=665
 GameBoyErrorBreakpointCondition9=
 GameBoyErrorBreakpointCondition8=