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diff --git a/drivers/gp2x_test/throttle.c b/drivers/gp2x_test/throttle.c
new file mode 100644
index 0000000..bf07099
--- /dev/null
+++ b/drivers/gp2x_test/throttle.c
@@ -0,0 +1,75 @@
+#include <sys/time.h>
+#include <unistd.h>
+
+#include "../gp2x/main.h"
+#include "../gp2x/gp2x.h"
+#include "../gp2x/throttle.h"
+
+
+extern uint8 PAL;
+extern int FSkip;
+static int usec_aim = 0, usec_done = 0;
+static int skip_count = 0;
+
+void RefreshThrottleFPS(void)
+{
+	usec_aim = usec_done = skip_count = 0;
+}
+
+void SpeedThrottle(void)
+{
+	static struct timeval tv_prev;
+	struct timeval tv_now;
+	int delta_nom = PAL ? 19997 : 16639; // ~50.007, 19.997 ms/frame : ~60.1, 16.639 ms/frame
+
+
+	if (usec_done == 0) { // first time
+		usec_done = 1;
+		gettimeofday(&tv_prev, 0);
+		return;
+	}
+
+	gettimeofday(&tv_now, 0);
+
+	usec_aim += delta_nom;
+	if (tv_now.tv_sec != tv_prev.tv_sec)
+		usec_done += 1000000;
+	usec_done += tv_now.tv_usec - tv_prev.tv_usec;
+
+#ifdef FRAMESKIP
+	if (Settings.frameskip >= 0)
+	{
+		if (skip_count >= Settings.frameskip)
+			skip_count = 0;
+		else {
+			skip_count++;
+			FSkip = 1;
+		}
+	}
+	else if (usec_done > usec_aim + 1024*4)
+	{
+		/* auto frameskip */
+		if (usec_done - usec_aim > 1024*32)
+			usec_done = usec_aim = 1; // too much behind, try to recover..
+		else
+			FSkip = 1;
+		tv_prev = tv_now;
+		return;
+	}
+#endif
+
+	tv_prev = tv_now;
+	while (usec_done < usec_aim)
+	{
+		usleep(300);
+		gettimeofday(&tv_now, 0);
+
+		if (tv_now.tv_sec != tv_prev.tv_sec)
+			usec_done += 1000000;
+		usec_done += tv_now.tv_usec - tv_prev.tv_usec;
+		tv_prev = tv_now;
+	}
+	usec_done = usec_done - usec_aim + 1; // reset to prevent overflows
+	usec_aim = 0;
+}
+