Fading LEDs

platform/sky/apps/fader.c

@@ -0,0 +1,174 @@
+/*
+ * Copyright (c) 2005, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file is part of the Contiki operating system.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ * $Id: fader.c,v 1.1 2007/03/21 23:17:28 adamdunkels Exp $
+ */
+
+#include "contiki.h"
+#include "dev/leds.h"
+
+PROCESS(fader_process, "LED fader");
+AUTOSTART_PROCESSES(&fader_process);
+
+#define ON  1
+#define OFF 0
+
+struct fader {
+  struct pt fade_pt, fade_in_pt, fade_out_pt;
+  struct etimer etimer;
+  int led;
+  int delay;
+};
+
+static unsigned char onoroff;
+
+/*---------------------------------------------------------------------------*/
+static
+PT_THREAD(fade_in(struct fader *f))
+{
+  PT_BEGIN(&f->fade_in_pt);
+  
+  for(f->delay = 3980; f->delay > 20; f->delay -= 20) {
+    leds_on(f->led);
+    clock_delay(4000 - f->delay);
+    leds_off(f->led);
+    clock_delay(f->delay);
+    PT_YIELD(&f->fade_in_pt);
+  }
+  
+  PT_END(&f->fade_in_pt);
+}
+/*---------------------------------------------------------------------------*/
+static
+PT_THREAD(fade_out(struct fader *f))
+{  
+  PT_BEGIN(&f->fade_out_pt);
+
+  for(f->delay = 20; f->delay < 3980; f->delay += 20) {
+    leds_on(f->led);
+    clock_delay(4000 - f->delay);
+    leds_off(f->led);
+    clock_delay(f->delay);
+    PT_YIELD(&f->fade_out_pt);
+  }
+    
+  PT_END(&f->fade_out_pt);
+}
+/*---------------------------------------------------------------------------*/
+static
+PT_THREAD(fade(struct fader *f))
+{
+  PT_BEGIN(&f->fade_pt);
+
+  while(1) {
+    
+    PT_SPAWN(&f->fade_pt, &f->fade_in_pt, fade_in(f));
+    PT_SPAWN(&f->fade_pt, &f->fade_out_pt, fade_out(f));
+    
+    etimer_set(&f->etimer, CLOCK_SECOND * 4);
+    PT_WAIT_UNTIL(&f->fade_pt, etimer_expired(&f->etimer));
+  }
+    
+  PT_END(&f->fade_pt);
+}
+/*---------------------------------------------------------------------------*/
+static void
+init_fader(struct fader *f, int led)
+{
+  PT_INIT(&f->fade_pt);
+  PT_INIT(&f->fade_in_pt);
+  PT_INIT(&f->fade_out_pt);
+  f->led = led;
+}
+/*---------------------------------------------------------------------------*/
+PROCESS_THREAD(fader_process, ev, data)
+{
+  static struct fader red, green, yellow;
+  static struct timer timer;
+  static struct etimer etimer;
+  
+  PROCESS_BEGIN();
+
+  init_fader(&red, LEDS_RED);
+  init_fader(&green, LEDS_GREEN);
+  init_fader(&yellow, LEDS_YELLOW);
+  
+  timer_set(&timer, CLOCK_SECOND/4);
+  while(!timer_expired(&timer)) {
+    PT_SCHEDULE(fade(&red));
+  }
+  timer_set(&timer, CLOCK_SECOND/4);
+  while(!timer_expired(&timer)) {
+    PT_SCHEDULE(fade(&red));
+    PT_SCHEDULE(fade(&green));
+  }
+  
+  timer_set(&timer, CLOCK_SECOND/4);
+  while(!timer_expired(&timer)) {
+    PT_SCHEDULE(fade(&green));
+    PT_SCHEDULE(fade(&yellow));
+  }
+
+  etimer_set(&etimer, CLOCK_SECOND * 4);
+  fader_on();
+  
+  while(1) {
+    PROCESS_WAIT_EVENT();
+  
+    if(ev == PROCESS_EVENT_TIMER) {
+      etimer_set(&etimer, CLOCK_SECOND * 4);
+      process_poll(&fader_process);
+    }
+    
+    if(onoroff == ON &&
+       PT_SCHEDULE(fade(&red)) &&
+       PT_SCHEDULE(fade(&yellow)) &&
+       PT_SCHEDULE(fade(&green))) {
+      process_poll(&fader_process);
+    }
+  }
+  PROCESS_END();
+}
+/*---------------------------------------------------------------------------*/
+void
+fader_on(void)
+{
+  onoroff = ON;
+  process_poll(&fader_process);
+}
+/*---------------------------------------------------------------------------*/
+void
+fader_off(void)
+{
+  onoroff = OFF;
+}
+/*---------------------------------------------------------------------------*/