Decompile sub_1157C

5 files changed, 70 insertions, 120 deletions

diff --git a/asm/titlescreen.s b/asm/titlescreen.s
index fde0f64..47f2c77 100755
--- a/asm/titlescreen.s
+++ b/asm/titlescreen.s
@@ -4,104 +4,6 @@
 
 	.text
 
-	thumb_func_start sub_1157C
-sub_1157C: @ 0x0801157C
-	push {r4, r5, r6, r7, lr}
-	ldr r6, _080115E4 @ =0x086A97AC
-	ldr r3, _080115E8 @ =0x020028A2
-	movs r0, #0
-	ldrsb r0, [r3, r0]
-	lsls r0, r0, #1
-	adds r0, r0, r6
-	ldrh r5, [r0]
-	ldr r2, _080115EC @ =gMain
-	ldrh r1, [r2, #0x1c]
-	movs r0, #0x10
-	ands r0, r1
-	adds r4, r2, #0
-	ldr r7, _080115F0 @ =0x020028A3
-	cmp r0, #0
-	beq _080115FC
-	ldrh r1, [r4, #0x18]
-	lsls r0, r5, #0x10
-	asrs r0, r0, #0x10
-	ands r1, r0
-	cmp r1, r0
-	bne _080115FC
-	movs r0, #0x28
-	strb r0, [r7]
-	ldrb r0, [r3]
-	adds r0, #1
-	strb r0, [r3]
-	movs r0, #0
-	ldrsb r0, [r3, r0]
-	lsls r0, r0, #1
-	adds r0, r0, r6
-	movs r2, #0
-	ldrsh r1, [r0, r2]
-	movs r0, #1
-	rsbs r0, r0, #0
-	cmp r1, r0
-	bne _080115FC
-	movs r0, #0
-	strb r0, [r3]
-	strb r0, [r7]
-	movs r0, #0x65
-	bl m4aSongNumStart
-	ldr r1, _080115F4 @ =gTitlescreen
-	movs r0, #5
-	strb r0, [r1, #6]
-	ldrb r0, [r4, #3]
-	cmp r0, #1
-	bne _080115F8
-	movs r0, #0xb
-	b _080115FA
-	.align 2, 0
-_080115E4: .4byte 0x086A97AC
-_080115E8: .4byte 0x020028A2
-_080115EC: .4byte gMain
-_080115F0: .4byte 0x020028A3
-_080115F4: .4byte gTitlescreen
-_080115F8:
-	movs r0, #0xa
-_080115FA:
-	strb r0, [r4, #3]
-_080115FC:
-	ldrh r0, [r4, #0x18]
-	ldr r1, _08011638 @ =0x000003FF
-	ands r0, r1
-	lsls r1, r5, #0x10
-	asrs r1, r1, #0x10
-	bics r0, r1
-	cmp r0, #0
-	beq _08011614
-	movs r1, #0
-	strb r1, [r7]
-	ldr r0, _0801163C @ =0x020028A2
-	strb r1, [r0]
-_08011614:
-	ldrb r1, [r7]
-	movs r0, #0
-	ldrsb r0, [r7, r0]
-	cmp r0, #0
-	ble _08011630
-	subs r0, r1, #1
-	strb r0, [r7]
-	lsls r0, r0, #0x18
-	cmp r0, #0
-	bgt _08011630
-	movs r1, #0
-	strb r1, [r7]
-	ldr r0, _0801163C @ =0x020028A2
-	strb r1, [r0]
-_08011630:
-	pop {r4, r5, r6, r7}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_08011638: .4byte 0x000003FF
-_0801163C: .4byte 0x020028A2
-
 	thumb_func_start sub_11640
 sub_11640: @ 0x08011640
 	push {r4, r5, r6, r7, lr}
diff --git a/data/rom.s b/data/rom.s
index a039f44..1c6d75f 100755
--- a/data/rom.s
+++ b/data/rom.s
@@ -192,7 +192,17 @@ gUnknown_086A9778:: @ 0x086A9778
 	.4byte 0x086A94F4
 	.4byte 0x00000000
 
-.incbin "baserom.gba", 0x6A97AC, 0x6B159C - 0x6A97AC
+gEReaderAccessButtonSequence:: @ 0x086A97AC
+	.2byte 0x0200
+	.2byte 0x0100
+	.2byte 0x0200
+	.2byte 0x0100
+	.2byte 0x0200
+	.2byte 0x0100
+	.2byte 0xFFFF
+
+	.align 2, 0
+.incbin "baserom.gba", 0x6A97BC, 0x6B159C - 0x6A97BC
 
 gMonHatchSpriteGroupPals:: @ 0x086B159C
 	.4byte gMonHatchSpriteGroup0_Pals
diff --git a/include/titlescreen.h b/include/titlescreen.h
index 65d790e..3fc4df8 100755
--- a/include/titlescreen.h
+++ b/include/titlescreen.h
@@ -26,10 +26,10 @@ extern struct TitlescreenStruct gTitlescreen;
 extern s8 gAutoDisplayTitlescreenMenu;
 extern u8 gUnknown_202BE24;
 extern u16 gUnknown_0202C588;
-extern s8 gUnknown_020028A0;
-extern s8 gUnknown_020028A1;
-extern u8 gUnknown_020028A2;
-extern u8 gUnknown_020028A3;
+extern s8 gEraseSaveDataAccessStep;
+extern s8 gEraseSaveDataAccessCounter;
+extern s8 gEReaderAccessStep;
+extern s8 gEReaderAccessCounter;
 extern s8 gUnknown_020028A4;
 extern s8 gUnknown_020028A5;
 extern const u8 *gUnknown_0201C190[];
diff --git a/src/titlescreen.c b/src/titlescreen.c
index c3e51a1..3c679c4 100755
--- a/src/titlescreen.c
+++ b/src/titlescreen.c
@@ -26,6 +26,7 @@ extern const u8 *const gUnknown_086A9778[];
 extern const s8 gUnknown_086A9672[9][2];
 extern const u16 gUnknown_086A96A4[];
 extern const u16 gUnknown_086A96D4[];
+extern const s16 gEReaderAccessButtonSequence[];
 
 extern void sub_2B4(void);
 extern void sub_438(void);
@@ -38,12 +39,12 @@ extern void sub_11640(void);
 extern void sub_52C44(void);
 
 extern void sub_10AC0(void);
-extern void sub_1157C(void);
 extern void sub_1175C(void);
 extern void sub_11968(void);
 extern void sub_11B74(void);
 
 static void sub_114FC(void);
+static void sub_1157C(void);
 
 // If the user doesn't press any buttons at the title screen,
 // it will transition to a demo gameplay experience.
@@ -125,10 +126,10 @@ void sub_10AC0(void)
     gTitlescreen.unkD = 0;
     gTitlescreen.unkF = 0;
     gUnknown_0202C588 = 1;
-    gUnknown_020028A0 = 0;
-    gUnknown_020028A1 = 0;
-    gUnknown_020028A2 = 0;
-    gUnknown_020028A3 = 0;
+    gEraseSaveDataAccessStep = 0;
+    gEraseSaveDataAccessCounter = 0;
+    gEReaderAccessStep = 0;
+    gEReaderAccessCounter = 0;
 
     if (gMain.unk40 == 1)
     {
@@ -635,11 +636,11 @@ static void sub_114FC(void)
     {
         if (gMain.newKeys & R_BUTTON)
         {
-            gUnknown_020028A1 = 40;
-            if (++gUnknown_020028A0 == 3)
+            gEraseSaveDataAccessCounter = 40;
+            if (++gEraseSaveDataAccessStep == 3)
             {
-                gUnknown_020028A0 = 0;
-                gUnknown_020028A1 = 0;
+                gEraseSaveDataAccessStep = 0;
+                gEraseSaveDataAccessCounter = 0;
                 m4aSongNumStart(0x68);
                 gTitlescreen.unk11 = 1;
                 gMain.subState = 9;
@@ -647,12 +648,49 @@ static void sub_114FC(void)
         }
     }
 
-    if (gUnknown_020028A1 > 0)
+    if (gEraseSaveDataAccessCounter > 0)
     {
-        if (--gUnknown_020028A1 <= 0)
+        if (--gEraseSaveDataAccessCounter <= 0)
         {
-            gUnknown_020028A1 = 0;
-            gUnknown_020028A0 = 0;
+            gEraseSaveDataAccessCounter = 0;
+            gEraseSaveDataAccessStep = 0;
+        }
+    }
+}
+
+static void sub_1157C(void)
+{
+    // To access the e-reader screen, alternate pressing R_BUTTON and L_BUTTON 6 times while holding DPAD_RIGHT.
+    s16 buttonMask = gEReaderAccessButtonSequence[gEReaderAccessStep];
+    if (gMain.heldKeys & DPAD_RIGHT && (gMain.newKeys & buttonMask) == buttonMask)
+    {
+        gEReaderAccessCounter = 40;
+        gEReaderAccessStep++;
+        if (gEReaderAccessButtonSequence[gEReaderAccessStep] == -1)
+        {
+            gEReaderAccessStep = 0;
+            gEReaderAccessCounter = 0;
+            m4aSongNumStart(0x65);
+            gTitlescreen.unk6 = 5;
+            if (gMain.subState == 1)
+                gMain.subState = 11;
+            else
+                gMain.subState = 10;
+        }
+    }
+
+    if (gMain.newKeys & (KEYS_MASK & ~buttonMask))
+    {
+        gEReaderAccessCounter = 0;
+        gEReaderAccessStep = 0;
+    }
+
+    if (gEReaderAccessCounter > 0)
+    {
+        if (--gEReaderAccessCounter <= 0)
+        {
+            gEReaderAccessCounter = 0;
+            gEReaderAccessStep = 0;
         }
     }
 }
diff --git a/sym_ewram.txt b/sym_ewram.txt
index 9e3af70..6cc4e1c 100755
--- a/sym_ewram.txt
+++ b/sym_ewram.txt
@@ -3,16 +3,16 @@
 gTitlescreen: @ 0x2002888
 	.space 0x18
 
-gUnknown_020028A0: @ 0x20028A0
+gEraseSaveDataAccessStep: @ 0x20028A0
 	.space 0x1
 
-gUnknown_020028A1: @ 0x20028A1
+gEraseSaveDataAccessCounter: @ 0x20028A1
 	.space 0x1
 
-gUnknown_020028A2: @ 0x20028A2
+gEReaderAccessStep: @ 0x20028A2
 	.space 0x1
 
-gUnknown_020028A3: @ 0x20028A3
+gEReaderAccessCounter: @ 0x20028A3
 	.space 0x1
 
 gUnknown_020028A4: @ 0x20028A4