diff --git a/asm/region_map.s b/asm/region_map.s
index 83687e02da..592ba9de91 100644
--- a/asm/region_map.s
+++ b/asm/region_map.s
@@ -5,108 +5,6 @@
 
 	.text
 
-	thumb_func_start _swiopen
-_swiopen: @ 8123190
-	push {r4,r5,lr}
-	ldr r5, =gUnknown_0203A144
-	ldr r1, [r5]
-	adds r0, r1, 0
-	adds r0, 0x7A
-	ldrb r0, [r0]
-	lsls r0, 24
-	asrs r0, 24
-	cmp r0, 0
-	beq _081231AC
-	movs r0, 0x2
-	b _08123248
-	.pool
-_081231AC:
-	adds r0, r1, 0
-	adds r0, 0x7B
-	ldrb r0, [r0]
-	lsls r0, 24
-	asrs r0, 24
-	cmp r0, 0
-	ble _081231C2
-	adds r1, 0x54
-	ldrh r0, [r1]
-	adds r0, 0x1
-	strh r0, [r1]
-_081231C2:
-	ldr r1, [r5]
-	adds r0, r1, 0
-	adds r0, 0x7B
-	ldrb r0, [r0]
-	lsls r0, 24
-	asrs r0, 24
-	cmp r0, 0
-	bge _081231DA
-	adds r1, 0x54
-	ldrh r0, [r1]
-	subs r0, 0x1
-	strh r0, [r1]
-_081231DA:
-	ldr r1, [r5]
-	adds r0, r1, 0
-	adds r0, 0x7C
-	ldrb r0, [r0]
-	lsls r0, 24
-	asrs r0, 24
-	cmp r0, 0
-	ble _081231F2
-	adds r1, 0x56
-	ldrh r0, [r1]
-	adds r0, 0x1
-	strh r0, [r1]
-_081231F2:
-	ldr r1, [r5]
-	adds r0, r1, 0
-	adds r0, 0x7C
-	ldrb r0, [r0]
-	lsls r0, 24
-	asrs r0, 24
-	cmp r0, 0
-	bge _0812320A
-	adds r1, 0x56
-	ldrh r0, [r1]
-	subs r0, 0x1
-	strh r0, [r1]
-_0812320A:
-	ldr r1, [r5]
-	adds r0, r1, 0
-	adds r0, 0x54
-	ldrh r0, [r0]
-	adds r1, 0x56
-	ldrh r1, [r1]
-	bl sub_812386C
-	lsls r0, 16
-	lsrs r4, r0, 16
-	adds r0, r4, 0
-	bl get_flagnr_blue_points
-	ldr r1, [r5]
-	strb r0, [r1, 0x2]
-	ldr r1, [r5]
-	ldrh r0, [r1]
-	cmp r4, r0
-	beq _0812323C
-	strh r4, [r1]
-	adds r0, r1, 0x4
-	ldrh r1, [r1]
-	movs r2, 0x10
-	bl GetMapName
-_0812323C:
-	bl sub_8123FB0
-	ldr r1, [r5]
-	ldr r0, =sub_81230C4
-	str r0, [r1, 0x18]
-	movs r0, 0x3
-_08123248:
-	pop {r4,r5}
-	pop {r1}
-	bx r1
-	.pool
-	thumb_func_end _swiopen
-
 	thumb_func_start sub_8123254
 sub_8123254: @ 8123254
 	push {r4-r6,lr}
diff --git a/include/region_map.h b/include/region_map.h
index 79e217f1fa..1f1f218f55 100644
--- a/include/region_map.h
+++ b/include/region_map.h
@@ -252,7 +252,7 @@ struct RegionMap {
     /*0x079*/ u8 unk_079;
     /*0x07a*/ s8 unk_07a;
     /*0x07b*/ s8 unk_07b;
-    /*0x07c*/ u8 unk_07c;
+    /*0x07c*/ s8 unk_07c;
     /*0x07d*/ u8 unk_07d;
     /*0x07e*/ u8 unk_07e;
     /*0x07f*/ u8 unk_07f;
@@ -265,6 +265,16 @@ struct RegionMap {
     /*0x284*/ u8 unk_284[0x600];
 }; // size = 0x884
 
+enum
+{
+    INPUT_EVENT_NONE,
+    INPUT_EVENT_MOVE_START,
+    INPUT_EVENT_MOVE_CONT,
+    INPUT_EVENT_MOVE_END,
+    INPUT_EVENT_A_BUTTON,
+    INPUT_EVENT_B_BUTTON,
+};
+
 // Exported RAM declarations
 
 // Exported ROM declarations
diff --git a/src/field_region_map.c b/src/field_region_map.c
index 74b62bbc79..2f73179d9e 100644
--- a/src/field_region_map.c
+++ b/src/field_region_map.c
@@ -150,11 +150,11 @@ void sub_8170290(void)
         case 4:
             switch (sub_81230AC())
             {
-                case 3:
+                case INPUT_EVENT_MOVE_END:
                     sub_8170428();
                     break;
-                case 4:
-                case 5:
+                case INPUT_EVENT_A_BUTTON:
+                case INPUT_EVENT_B_BUTTON:
                     gUnknown_0203BCD0->state ++;
                     break;
             }
diff --git a/src/region_map.c b/src/region_map.c
index 7d3db9c8b1..894937c6d2 100644
--- a/src/region_map.c
+++ b/src/region_map.c
@@ -13,17 +13,6 @@ struct UnkStruct_0203A148 {
     u8 filler_000[0xa74];
 };
 
-enum
-{
-    INPUT_EVENT_NONE,
-    INPUT_EVENT_DPAD,
-    INPUT_EVENT_2,
-    INPUT_EVENT_3,
-    INPUT_EVENT_A_BUTTON,
-    INPUT_EVENT_B_BUTTON,
-};
-
-
 // Static RAM declarations
 
 EWRAM_DATA struct RegionMap *gUnknown_0203A144 = NULL;
@@ -40,6 +29,7 @@ u8 get_flagnr_blue_points(u16 mapSecId);
 u16 sub_8123EB4(u16 mapSecId);
 void sub_8123FB0(void);
 u8 _swiopen(void);
+u16 sub_812386C(u16 x, u16 y);
 
 // .rodata
 
@@ -209,22 +199,22 @@ u8 sub_81230C4(void)
     if (gMain.heldKeys & DPAD_UP && gUnknown_0203A144->unk_056 > 2)
     {
         gUnknown_0203A144->unk_07c = -1;
-        input = INPUT_EVENT_DPAD;
+        input = INPUT_EVENT_MOVE_START;
     }
     if (gMain.heldKeys & DPAD_DOWN && gUnknown_0203A144->unk_056 < 16)
     {
         gUnknown_0203A144->unk_07c = +1;
-        input = INPUT_EVENT_DPAD;
+        input = INPUT_EVENT_MOVE_START;
     }
     if (gMain.heldKeys & DPAD_LEFT && gUnknown_0203A144->unk_054 > 1)
     {
         gUnknown_0203A144->unk_07b = -1;
-        input = INPUT_EVENT_DPAD;
+        input = INPUT_EVENT_MOVE_START;
     }
     if (gMain.heldKeys & DPAD_RIGHT && gUnknown_0203A144->unk_054 < 28)
     {
         gUnknown_0203A144->unk_07b = +1;
-        input = INPUT_EVENT_DPAD;
+        input = INPUT_EVENT_MOVE_START;
     }
     if (gMain.newKeys & A_BUTTON)
     {
@@ -234,10 +224,46 @@ u8 sub_81230C4(void)
     {
         input = INPUT_EVENT_B_BUTTON;
     }
-    if (input == INPUT_EVENT_DPAD)
+    if (input == INPUT_EVENT_MOVE_START)
     {
         gUnknown_0203A144->unk_07a = 4;
         gUnknown_0203A144->inputCallback = _swiopen;
     }
     return input;
 }
+
+u8 _swiopen(void)
+{
+    u16 mapSecId;
+
+    if (gUnknown_0203A144->unk_07a != 0)
+    {
+        return INPUT_EVENT_MOVE_CONT;
+    }
+    if (gUnknown_0203A144->unk_07b > 0)
+    {
+        gUnknown_0203A144->unk_054 ++;
+    }
+    if (gUnknown_0203A144->unk_07b < 0)
+    {
+        gUnknown_0203A144->unk_054 --;
+    }
+    if (gUnknown_0203A144->unk_07c > 0)
+    {
+        gUnknown_0203A144->unk_056 ++;
+    }
+    if (gUnknown_0203A144->unk_07c < 0)
+    {
+        gUnknown_0203A144->unk_056 --;
+    }
+    mapSecId = sub_812386C(gUnknown_0203A144->unk_054, gUnknown_0203A144->unk_056);
+    gUnknown_0203A144->unk_002 = get_flagnr_blue_points(mapSecId);
+    if (mapSecId != gUnknown_0203A144->mapSecId)
+    {
+        gUnknown_0203A144->mapSecId = mapSecId;
+        GetMapName(gUnknown_0203A144->mapSecName, gUnknown_0203A144->mapSecId, 16);
+    }
+    sub_8123FB0();
+    gUnknown_0203A144->inputCallback = sub_81230C4;
+    return INPUT_EVENT_MOVE_END;
+}