diff --git a/os_functions.c b/os_functions.c
index a87aa33..734e2e5 100644
--- a/os_functions.c
+++ b/os_functions.c
@@ -51,6 +51,8 @@ EXPORT_DECL(void, OSDetachThread, void * thread);
 EXPORT_DECL(void, OSSleepTicks, u64 ticks);
 EXPORT_DECL(u64, OSGetTick, void);
 EXPORT_DECL(u64, OSGetTime, void);
+EXPORT_DECL(void, OSTicksToCalendarTime, u64 time, OSCalendarTime * calendarTime);
+
 
 //!----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 //! Mutex functions
@@ -194,6 +196,8 @@ void InitOSFunctionPointers(void)
     OS_FIND_EXPORT(coreinit_handle, OSSleepTicks);
     OS_FIND_EXPORT(coreinit_handle, OSGetTick);
     OS_FIND_EXPORT(coreinit_handle, OSGetTime);
+    OS_FIND_EXPORT(coreinit_handle, OSTicksToCalendarTime);
+
     //!----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
     //! Mutex functions
     //!----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
diff --git a/os_functions.h b/os_functions.h
index 29bad5f..347da67 100644
--- a/os_functions.h
+++ b/os_functions.h
@@ -26,6 +26,7 @@
 
 #include <gctypes.h>
 #include "common/os_defs.h"
+#include "os_types.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -93,6 +94,7 @@ extern void (* OSDetachThread)(void * thread);
 extern void (* OSSleepTicks)(u64 ticks);
 extern u64 (* OSGetTick)(void);
 extern u64 (* OSGetTime)(void);
+extern void (*OSTicksToCalendarTime)(u64 time, OSCalendarTime *calendarTime);
 
 //!----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 //! Mutex functions
diff --git a/os_types.h b/os_types.h
new file mode 100644
index 0000000..aaa18fe
--- /dev/null
+++ b/os_types.h
@@ -0,0 +1,27 @@
+#ifndef _OS_TYPES_H_
+#define _OS_TYPES_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <gctypes.h>
+
+typedef struct _OSCalendarTime {
+  int sec;
+  int min;
+  int hour;
+  int mday;
+  int mon;
+  int year;
+  int wday;
+  int yday;
+  int msec;
+  int usec;
+} OSCalendarTime;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif