diff --git a/include/sta/event.hpp b/include/sta/event.hpp
new file mode 100644
index 0000000..dce0b9e
--- /dev/null
+++ b/include/sta/event.hpp
@@ -0,0 +1,47 @@
+/**
+ * @file
+ * @brief Event interface definition.
+ */
+#ifndef STA_CORE_EVENT_HPP
+#define STA_CORE_EVENT_HPP
+
+
+namespace sta
+{
+    /**
+     * @brief Interface for event objects.
+     *
+     * @ingroup sta_core
+     */
+    class Event
+    {
+    public:
+        /**
+         * @brief Set event flag.
+         * 
+         * @param Flag nr. to set 
+         */
+        virtual void set(uint32_t flags) = 0;
+        /**
+         * @brief Clear event flag.
+         *
+         * @param Flag nr. to clear
+         */
+        virtual void clear(uint32_t flags) = 0;
+        /**
+         * @brief Check event flag state w/o changing it.
+         *
+         * @return Value of event flag
+         */
+        virtual uint32_t get() = 0;
+        /**
+         * @brief Wait until event flag is set. Timeout default to forever.
+         * 
+         * @param Event flag nr. to wait for.
+         */
+        virtual uint32_t wait(uint32_t flags, uint32_t timeout = osWaitForever) = 0;
+    };
+} // namespace sta
+
+
+#endif //STA_CORE_EVENT_HPP
diff --git a/include/sta/timer.hpp b/include/sta/timer.hpp
new file mode 100644
index 0000000..f8c8a72
--- /dev/null
+++ b/include/sta/timer.hpp
@@ -0,0 +1,34 @@
+/**
+ * @file
+ * @brief Timer interface definition.
+ */
+#ifndef STA_CORE_TIMER_HPP
+#define STA_CORE_TIMER_HPP
+
+
+namespace sta
+{
+    /**
+     * @brief Interface for timer objects.
+     *
+     * @ingroup sta_core
+     */
+    class Timer
+    {
+    public:
+        /**
+         * @brief Start Timer.
+         * 
+         * @param time in milliseconds
+         */
+        virtual void start(uint32_t millis) = 0;
+        /**
+         * @brief Stop Timer.
+         *
+         */
+        virtual void stop() = 0;
+    };
+} // namespace sta
+
+
+#endif //STA_CORE_TIMER_HPP
\ No newline at end of file