diff --git a/source/os/debug/include/board_devices.h b/source/os/debug/include/board_devices.h
new file mode 100644
index 0000000..16ace5b
--- /dev/null
+++ b/source/os/debug/include/board_devices.h
@@ -0,0 +1,12 @@
+/* Board devices include file */
+
+#ifndef BOARD_DEVICES_H
+#define BOARD_DEVICES_H
+
+extern const struct driver uart_1;
+extern const struct driver led_3;
+extern const struct driver led_4;
+extern const struct driver led_5;
+extern const struct driver led_6;
+
+#endif /* BOARD_DEVICES_H */
diff --git a/source/os/debug/include/driver.h b/source/os/debug/include/driver.h
new file mode 100644
index 0000000..ee82abf
--- /dev/null
+++ b/source/os/debug/include/driver.h
@@ -0,0 +1,30 @@
+/*
+ * driver.h
+ *
+ *  Created on: Jul 27, 2016
+ *      Author: tkl
+ */
+
+#ifndef SOURCE_FIRMWARE_KERNEL_DRIVER_INCLUDE_DRIVER_H_
+#define SOURCE_FIRMWARE_KERNEL_DRIVER_INCLUDE_DRIVER_H_
+
+enum driver_type {
+	DRIVER_TYPE_ADC,
+	DRIVER_TYPE_GPIO,
+	DRIVER_TYPE_I2C,
+	DRIVER_TYPE_RTC,
+	DRIVER_TYPE_SPI,
+	DRIVER_TYPE_UART
+};
+
+struct driver {
+	enum driver_type driver_type;
+	const void *device_driver;
+};
+
+int open(const struct driver *driver);
+int close(const struct driver *driver);
+int read(const struct driver *driver, char *buffer, int len);
+int write(const struct driver *driver, const char *buffer, int len);
+
+#endif /* SOURCE_FIRMWARE_KERNEL_DRIVER_INCLUDE_DRIVER_H_ */
diff --git a/source/os/debug/include/kernel.h b/source/os/debug/include/kernel.h
new file mode 100644
index 0000000..b9d4520
--- /dev/null
+++ b/source/os/debug/include/kernel.h
@@ -0,0 +1,51 @@
+/*
+ * kernel.h
+ *
+ *  Created on: Jul 28, 2016
+ *      Author: tkl
+ */
+
+#ifndef SOURCE_FIRMWARE_KERNEL_INTERFACE_KERNEL_H_
+#define SOURCE_FIRMWARE_KERNEL_INTERFACE_KERNEL_H_
+
+void schedule_start(void);
+
+enum thread_priority {
+	THREAD_PRIO_IDLE = 0,
+	THREAD_PRIO_LOW,
+	THREAD_PRIO_MEDIUM,
+	THREAD_PRIO_HIGH
+};
+
+enum thread_status {
+	THREAD_STATUS_INIT = 0,
+	THREAD_STATUS_EXECUTING,
+	THREAD_STATUS_WAITING,
+	THREAD_STATUS_SLEEPING,
+	THREAD_STATUS_BLOCKING
+};
+
+struct thread_context {
+	stack_t *sp;					/**< thread's stack pointer */
+	stack_t *stack;					/**< thread's stack start address */
+	unsigned int stack_size;		/**< thread's stack size */
+	unsigned int pid;				/**< thread's process id */
+	enum thread_priority priority;	/**< thread's priority */
+	enum thread_status status;		/**< thread's status */
+	unsigned long next_executing_time;
+	void *wakeup_blocking_source;
+	struct queue_node sem_queue_node;
+};
+
+struct thread_context *thread_create(
+		struct thread_context *thread,
+		stack_t *stack,
+		unsigned int stack_size,
+		void (*thread_func)(void *),
+		void *arg,
+		enum thread_priority priority);
+
+void thread_exit(void);
+void sleep_ms(unsigned int ms);
+
+#endif /* SOURCE_FIRMWARE_KERNEL_INTERFACE_KERNEL_H_ */
diff --git a/source/os/debug/include/queue.h b/source/os/debug/include/queue.h
new file mode 100644
index 0000000..996ef90
--- /dev/null
+++ b/source/os/debug/include/queue.h
@@ -0,0 +1,26 @@
+/*
+ * queue.h
+ *
+ *  Created on: Oct 25, 2015
+ *      Author: tkl
+ */
+
+#ifndef QUEUE_H_
+#define QUEUE_H_
+
+struct queue_node {
+	struct queue_node *next;
+	unsigned int data;
+};
+
+struct queue {
+	struct queue_node *front;
+	struct queue_node *rear;
+};
+
+int queue_init(struct queue *head);
+int queue_push(struct queue *head, struct queue_node *node);
+int queue_pop(struct queue *head, struct queue_node *node);
+bool queue_is_empty(struct queue *head);
+
+#endif /* QUEUE_H_ */
diff --git a/source/os/debug/include/stack.h b/source/os/debug/include/stack.h
new file mode 100644
index 0000000..b792758
--- /dev/null
+++ b/source/os/debug/include/stack.h
@@ -0,0 +1,8 @@
+/* Stack include file */
+
+#ifndef STACK_H
+#define STACK_H
+
+typedef uint32_t stack_t;
+
+#endif /* STACK_H */
diff --git a/source/os/debug/libkosmos-arm-stm32f4-discovery-dbg.a b/source/os/debug/libkosmos-arm-stm32f4-discovery-dbg.a
new file mode 100644
index 0000000..f28c1b9
Binary files /dev/null and b/source/os/debug/libkosmos-arm-stm32f4-discovery-dbg.a differ