+/* ambient.c */
+void ambient_init();
+extern volatile unsigned char ambient_zone;
+void ambient_adc(uint16_t adc_val);
+
+/* pattern.c */
+void pattern_init();
+void patterns_next_tick();
+void led_set_status(unsigned char status);
+
+/* buttons.c */
+void init_buttons();
+void timer_check_buttons();
+