From faf0f2ea0a736baab288fe389dc44a6b295fb6d5 Mon Sep 17 00:00:00 2001
From: joxe <joxe>
Date: Fri, 25 Apr 2008 16:34:31 +0000
Subject: [PATCH] added fft test program sampling using the esb-mic.

---
 examples/esb/fft-test.c | 138 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 138 insertions(+)
 create mode 100644 examples/esb/fft-test.c

diff --git a/examples/esb/fft-test.c b/examples/esb/fft-test.c
new file mode 100644
index 000000000..822373e0c
--- /dev/null
+++ b/examples/esb/fft-test.c
@@ -0,0 +1,138 @@
+/*
+ * Copyright (c) 2008, 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.
+ *
+ * $Id: fft-test.c,v 1.1 2008/04/25 16:34:31 joxe Exp $
+ *
+ * -----------------------------------------------------------------
+ * fft-test - a test program that use the sound sensor for sampling
+ * some data and then performs an FFT on that. Then flashes leds based
+ * on energy-level and position of highest frequency band.
+ *
+ * Author  : Joakim Eriksson
+ * Created : 2008-04-04
+ * Updated : $Date: 2008/04/25 16:34:31 $
+ *           $Revision: 1.1 $
+ */
+
+#include "contiki-esb.h"
+#include "dev/sound-sensor.h"
+#include <stdio.h>
+#include "lib/ifft.h"
+
+#define FFT_TEST_SIZE 128
+
+PROCESS(fft_process, "Fft");
+
+AUTOSTART_PROCESSES(&fft_process);
+
+PROCESS_THREAD(fft_process, ev, data)
+{
+  static struct etimer etimer;
+  static int on = 0;
+  static int i = 0;
+  static int mode = 0;
+  static int16_t fftBuf[FFT_TEST_SIZE];
+  static int max_value = 0;
+  static int max_pos = 0;
+
+  PROCESS_EXITHANDLER(goto exit);
+  PROCESS_BEGIN();
+
+  etimer_set(&etimer, CLOCK_SECOND * 4);
+  button_sensor.activate();
+  /* start and configure the sound sensor for sampling */
+  sound_sensor.activate();
+  sound_sensor.configure(SOUND_SET_BUFFER_PTR, fftBuf);
+  sound_sensor.configure(SOUND_SET_BUFFER_SIZE, (void *) FFT_TEST_SIZE);
+  sound_sensor.configure(SOUND_SET_DIV, (void *) 1);
+  while(1) {
+
+    PROCESS_WAIT_EVENT();
+
+    if(ev == sensors_event) {
+      if(data == &button_sensor) {
+	beep_beep(100);
+	mode = !mode;
+      } else if(data == &sound_sensor) {
+	for(i = 0; i < FFT_TEST_SIZE; i++) {
+	  fftBuf[i] = -128 + (fftBuf[i] >> 4);
+	  if(!mode) {
+	    /* just print the samples if mode = 0 */
+	    if(i > 0) {
+	      printf(" ");
+	    }
+	    printf("%d", fftBuf[i]);
+	  }
+	}
+	if (mode) {
+	  /* Calculate fft, print result, and find index of
+             highest energy level */
+	  ifft(fftBuf, FFT_TEST_SIZE);
+	  max_value = 0;
+	  max_pos = 0;
+	  for (i = 0; i < FFT_TEST_SIZE/2; i++) {
+	    if(i > 0) {
+	      printf(" ");
+	    }
+	    printf("%d", fftBuf[i]);
+
+	    if(max_value < fftBuf[i]) {
+	      max_value = fftBuf[i];
+	      max_pos = i;
+	    }
+	  }
+	  /* flash leds based on energy level and position of max */
+	  if(max_value < 400 || max_pos < 2) {
+	    leds_off(LEDS_ALL);
+	  } else if (max_pos > 1 && max_pos < 15) {
+	    leds_on(LEDS_GREEN);
+	  } else if(max_pos < 25) {
+	    leds_on(LEDS_YELLOW);
+	  } else {
+	    leds_on(LEDS_RED);
+	  }
+	}
+	printf("\n");
+	printf("#Maxval: %d, maxpos: %d\n", max_value, max_pos);
+      }
+    } else if(ev == PROCESS_EVENT_TIMER) {
+      if(data == &etimer) {
+	if(on) {
+	  sound_sensor.configure(SOUND_START_SAMPLE, NULL);
+	  leds_off(LEDS_ALL);
+	}
+	etimer_set(&etimer, CLOCK_SECOND / 2);
+	on = !on;
+      }
+    }
+  }
+
+ exit:
+  leds_off(LEDS_ALL);
+  PROCESS_END();
+}