diff --git a/asm/link_rfu.s b/asm/link_rfu.s
index adc7e7d82..47e3526e7 100644
--- a/asm/link_rfu.s
+++ b/asm/link_rfu.s
@@ -5,136 +5,6 @@
 
 	.text
 
-	thumb_func_start sub_800D434
-sub_800D434: @ 800D434
-	push {r4-r7,lr}
-	mov r7, r10
-	mov r6, r9
-	mov r5, r8
-	push {r5-r7}
-	sub sp, 0x4
-	ldr r0, =gUnknown_03004140
-	ldrh r0, [r0, 0x18]
-	cmp r0, 0
-	beq _0800D510
-	ldr r0, =gUnknown_03007890
-	ldr r0, [r0]
-	ldrb r0, [r0, 0x4]
-	cmp r0, 0
-	beq _0800D4D4
-	movs r6, 0
-_0800D454:
-	ldr r3, =gUnknown_03007880
-	lsls r2, r6, 2
-	adds r0, r2, r3
-	ldr r0, [r0]
-	ldrh r1, [r0]
-	movs r4, 0x80
-	lsls r4, 8
-	adds r0, r4, 0
-	ands r1, r0
-	adds r7, r2, 0
-	adds r0, r6, 0x1
-	mov r9, r0
-	cmp r1, 0
-	beq _0800D4CA
-	movs r5, 0
-	movs r4, 0
-	movs r1, 0x1
-	mov r8, r1
-	mov r10, r3
-_0800D47A:
-	adds r0, r7, r3
-	ldr r0, [r0]
-	ldrb r0, [r0, 0x1A]
-	asrs r0, r4
-	mov r1, r8
-	ands r0, r1
-	cmp r0, 0
-	beq _0800D4A4
-	lsls r0, r4, 2
-	adds r0, r3
-	ldr r0, [r0]
-	ldr r1, =gUnknown_03004140
-	ldrh r0, [r0, 0x2]
-	ldrh r1, [r1, 0x18]
-	cmp r0, r1
-	bls _0800D4A4
-	mov r0, r8
-	lsls r0, r4
-	orrs r5, r0
-	lsls r0, r5, 24
-	lsrs r5, r0, 24
-_0800D4A4:
-	cmp r5, 0
-	beq _0800D4C0
-	mov r1, r10
-	adds r0, r7, r1
-	ldr r0, [r0]
-	ldrb r0, [r0, 0x1A]
-	adds r2, r5, 0
-	eors r2, r0
-	movs r0, 0x20
-	adds r1, r6, 0
-	str r3, [sp]
-	bl rfu_changeSendTarget
-	ldr r3, [sp]
-_0800D4C0:
-	adds r0, r4, 0x1
-	lsls r0, 24
-	lsrs r4, r0, 24
-	cmp r4, 0x3
-	bls _0800D47A
-_0800D4CA:
-	mov r3, r9
-	lsls r0, r3, 24
-	lsrs r6, r0, 24
-	cmp r6, 0x3
-	bls _0800D454
-_0800D4D4:
-	ldr r0, =gUnknown_03007890
-	ldr r0, [r0]
-	ldrb r0, [r0, 0x5]
-	cmp r0, 0
-	beq _0800D510
-	movs r6, 0
-_0800D4E0:
-	ldr r1, =gUnknown_03007880
-	lsls r0, r6, 2
-	adds r0, r1
-	ldr r2, [r0]
-	ldrh r0, [r2, 0x34]
-	movs r4, 0x80
-	lsls r4, 8
-	adds r1, r4, 0
-	ands r0, r1
-	cmp r0, 0
-	beq _0800D506
-	ldr r1, =gUnknown_03004140
-	ldrh r0, [r2, 0x36]
-	ldrh r1, [r1, 0x18]
-	cmp r0, r1
-	bls _0800D506
-	adds r0, r6, 0
-	bl rfu_NI_stopReceivingData
-_0800D506:
-	adds r0, r6, 0x1
-	lsls r0, 24
-	lsrs r6, r0, 24
-	cmp r6, 0x3
-	bls _0800D4E0
-_0800D510:
-	add sp, 0x4
-	pop {r3-r5}
-	mov r8, r3
-	mov r9, r4
-	mov r10, r5
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_800D434
-
 	thumb_func_start sub_800D52C
 sub_800D52C: @ 800D52C
 	push {lr}
diff --git a/include/librfu.h b/include/librfu.h
index 8d61c2559..90bae1dbb 100644
--- a/include/librfu.h
+++ b/include/librfu.h
@@ -117,11 +117,13 @@ struct RfuUnk1
 struct RfuUnk2
 {
     u16 unk_0;
-    u8 fill_2[0x18];
+    u16 unk_2;
+    u8 fill_4[0x16];
     u8 unk_1a;
     u8 fill_1b[0x19];
     u16 unk_34;
-    u8 fill_36[0x18];
+    u16 unk_36;
+    u8 fill_38[0x16];
     u8 unk_4e;
     u8 fill_4f[0x12];
     u8 unk_61;
diff --git a/src/link_rfu.c b/src/link_rfu.c
index ffe119a17..e47a42bb4 100644
--- a/src/link_rfu.c
+++ b/src/link_rfu.c
@@ -35,7 +35,7 @@ static u8 sub_800D294(void);
 void sub_800D30C(u8 a0, u8 a1);
 static void sub_800D334(u8 a0);
 static void sub_800D358(u8 a0);
-void sub_800D434(void);
+static void sub_800D434(void);
 void sub_800D610(void);
 void sub_800D630(void);
 
@@ -1263,3 +1263,45 @@ static void sub_800D358(u8 a0)
         }
     }
 }
+
+static void sub_800D434(void)
+{
+    u8 i;
+    u8 j;
+    u8 flags;
+
+    if (gUnknown_03004140.unk_18)
+    {
+        if (gUnknown_03007890->unk_04)
+        {
+            for (i = 0; i < 4; i ++)
+            {
+                if (gUnknown_03007880[i]->unk_0 & 0x8000)
+                {
+                    flags = 0;
+                    for (j = 0; j < 4; j++)
+                    {
+                        if ((gUnknown_03007880[i]->unk_1a >> j) & 1 && gUnknown_03007880[j]->unk_2 > gUnknown_03004140.unk_18)
+                        {
+                            flags |= (1 << j);
+                        }
+                        if (flags)
+                        {
+                            rfu_changeSendTarget(0x20, i, flags ^ gUnknown_03007880[i]->unk_1a);
+                        }
+                    }
+                }
+            }
+        }
+        if (gUnknown_03007890->unk_05)
+        {
+            for (i = 0; i < 4; i++)
+            {
+                if (gUnknown_03007880[i]->unk_34 & 0x8000 && gUnknown_03007880[i]->unk_36 > gUnknown_03004140.unk_18)
+                {
+                    rfu_NI_stopReceivingData(i);
+                }
+            }
+        }
+    }
+}