+#define GPIOB 0x40020400 /* port B */
+#define GPIOB_MODER (GPIOB + 0x00) /* port mode register */
+#define LED_PORT_ODR (GPIOB + 0x14) /* port output data register */
+
+#define LED_BLUE (1 << 6) /* port B, pin 6 */
+#define LED_GREEN (1 << 7) /* port B, pin 7 */
+#define LED_ORANGE 0
+#define LED_RED 0
+
+static inline void setup_leds(void)