3 files changed, 71 insertions, 0 deletions
diff --git a/arm7/lib/include/OS_tick.h b/arm7/lib/include/OS_tick.h
new file mode 100644
index 00000000..7ee9544a
--- /dev/null
+++ b/arm7/lib/include/OS_tick.h
@@ -0,0 +1,11 @@
+#ifndef POKEDIAMOND_OS_TICK_H
+#define POKEDIAMOND_OS_TICK_H
+
+#include "nitro/OS_tick_shared.h"
+
+void OS_InitTick(void);
+u16 OS_IsTickAvailable(void);
+void OSi_CountUpTick(void);
+OSTick OS_GetTick(void);
+
+#endif
diff --git a/arm7/lib/include/OS_timer.h b/arm7/lib/include/OS_timer.h
new file mode 100644
index 00000000..fee42c6f
--- /dev/null
+++ b/arm7/lib/include/OS_timer.h
@@ -0,0 +1,6 @@
+#ifndef POKEDIAMOND_OS_TIMER_H
+#define POKEDIAMOND_OS_TIMER_H
+
+#include "nitro/OS_timer_shared.h"
+
+#endif 
diff --git a/arm7/lib/src/OS_tick.c b/arm7/lib/src/OS_tick.c
new file mode 100644
index 00000000..e45b6833
--- /dev/null
+++ b/arm7/lib/src/OS_tick.c
@@ -0,0 +1,54 @@
+#include "OS_interrupt.h"
+#include "OS_system.h"
+#include "OS_tick.h"
+#include "OS_timer.h"
+#include "function_target.h"
+
+extern void OSi_SetTimerReserved(u32);
+
+static u16 OSi_UseTick;
+static OSTick OSi_TickCounter;
+static BOOL OSi_NeedResetTimer;
+
+ARM_FUNC void OS_InitTick(void) {
+    if (OSi_UseTick == 0) {
+        OSi_UseTick = 1;
+        OSi_SetTimerReserved(0);
+        OSi_TickCounter = 0;
+        OS_SetTimerControl(OS_TIMER_0, 0);
+        OS_SetTimerCount(OS_TIMER_0, 0);
+        OS_SetTimerControl(OS_TIMER_0, 0xc1);
+        OS_SetIrqFunction(8, OSi_CountUpTick);
+        (void)OS_EnableIrqMask(8);
+        OSi_NeedResetTimer = 0;
+    }
+}
+
+ARM_FUNC u16 OS_IsTickAvailable(void) {
+    return OSi_UseTick;
+}
+
+ARM_FUNC void OSi_CountUpTick(void) {
+    OSi_TickCounter++;
+    if (OSi_NeedResetTimer != 0) {
+        OS_SetTimerControl(OS_TIMER_0, 0);
+        OS_SetTimerCount(OS_TIMER_0, 0);
+        OS_SetTimerControl(OS_TIMER_0, 0xc1);
+        OSi_NeedResetTimer = 0;
+    }
+    OSi_EnterTimerCallback(0, (void(*)(void*))OSi_CountUpTick, NULL);
+}
+
+ARM_FUNC OSTick OS_GetTick(void) {
+    OSIntrMode prev = OS_DisableInterrupts();
+    vu16 countL = *(REGType16 *)((u32)&reg_OS_TM0CNT_L + OS_TIMER_0 * 4);
+    vu64 countH = OSi_TickCounter & 0xffffffffffffULL;
+
+    if (reg_OS_IF & 8 && !(countL & 0x8000)) {
+        countH++;
+    }
+
+    (void)OS_RestoreInterrupts(prev);
+
+    return (countH << 16) | countL;
+}