diff --git a/src/libultra/voice/voicemaskdictionary.c b/src/libultra/voice/voicemaskdictionary.c
index e82a27b81..21c01b8a5 100644
--- a/src/libultra/voice/voicemaskdictionary.c
+++ b/src/libultra/voice/voicemaskdictionary.c
@@ -1,4 +1,49 @@
 #include "global.h"
 
 // Mask words registered in the voice recognition system
-#pragma GLOBAL_ASM("asm/non_matchings/boot/voicemaskdictionary/osVoiceMaskDictionary.s")
+s32 osVoiceMaskDictionary(OSVoiceHandle* hd, u8* maskPattern, s32 size) {
+    s32 errorCode;
+    s32 i;
+    s32 sp3C;
+    u8 status;
+    u8 data[20];
+
+    errorCode = __osVoiceGetStatus(hd->mq, hd->port, &status);
+    if (errorCode != 0) {
+        return errorCode;
+    }
+
+    if (status & 2) {
+        return CONT_ERR_VOICE_NO_RESPONSE;
+    }
+
+    if (size & 1) {
+        sp3C = size + 1;
+    } else {
+        sp3C = size;
+    }
+
+    bzero(&data, 20);
+
+    data[18 - sp3C] = 4;
+
+    for (i = 0; i < sp3C; i += 2) {
+        data[i + 20 - sp3C] = maskPattern[i];
+        data[i + 21 - sp3C] = maskPattern[i+1];
+    }
+
+    if (size & 1) {
+        data[19] = 0;
+    }
+
+    errorCode = __osVoiceContWrite20(hd->mq, hd->port, 0, &data);
+    if (errorCode == 0) {
+        errorCode = __osVoiceCheckResult(hd, &status);
+        if (errorCode & 0xFF00) {
+            errorCode = CONT_ERR_INVALID;
+        }
+    }
+
+    return errorCode;
+}
+