diff --git a/mu3io/mu3io.c b/mu3io/mu3io.c
index 63b9652..0bbd37f 100644
--- a/mu3io/mu3io.c
+++ b/mu3io/mu3io.c
@@ -12,6 +12,11 @@ static uint8_t mu3_right_btn;
 static int16_t mu3_lever_pos;
 static int16_t mu3_lever_xpos;
 
+uint16_t mu3_io_get_api_version(void)
+{
+    return 0x0100;
+}
+
 HRESULT mu3_io_init(void)
 {
     return S_OK;
diff --git a/mu3io/mu3io.h b/mu3io/mu3io.h
index fb140eb..9a006ca 100644
--- a/mu3io/mu3io.h
+++ b/mu3io/mu3io.h
@@ -17,6 +17,8 @@ enum {
     MU3_IO_GAMEBTN_MENU = 0x10,
 };
 
+uint16_t mu3_io_get_api_version(void);
+
 HRESULT mu3_io_init(void);
 
 HRESULT mu3_io_poll(void);