Add virtual timer

src/virtual_timer/VirtualTimer.h

@@ -0,0 +1,30 @@
+#ifndef __VIRTUAL_TIMER_VIRTUALTIMER_H__
+#define __VIRTUAL_TIMER_VIRTUALTIMER_H__
+
+#include "VirtualTimerInterface.h"
+
+namespace pinetime::virtual_timer
+{
+
+class VirtualTimer
+    : public pinetime::interfaces::VirtualTimerInterface
+{
+public:
+    VirtualTimer(uint64_t);
+
+    void timer_enable() override;
+    void timer_disable() override;
+    void timer_notification(uint64_t) override;
+
+    void timer_set_period_ms(uint64_t);
+
+    virtual void notification() = 0;
+
+private:
+    uint64_t period;
+    uint64_t start_time;
+};
+
+}
+
+#endif