Diff: beeper.cpp

Revision:

0:85829f7bbe62

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/beeper.cpp	Mon Jun 04 13:51:43 2012 +0000
@@ -0,0 +1,56 @@
+/*
+ * PROGRAM RESPONSIBLE FOR BEEPING.
+ * ^^^^^^^ ^^^^^^^^^^^ ^^^ ^^^^^^^
+ *
+ * FILE NAME: beeper.cpp
+ * USAGE: a simple beep program.
+ */
+
+
+
+/*
+* including the wanted library files.
+*/
+#include "mbed.h"
+#include "beeper.h"
+#include "main.h"
+
+AnalogOut beeper(p18); /*set the voltage of an analog output pin*/
+Ticker bing_timer; /* using ticker class which repeatedly call a function*/
+
+/*--------------------------*\
+ *  defineding the variables*
+\*--------------------------*/
+const signed short *ptr;
+signed short a;
+int b;
+unsigned short c;
+int order;
+
+void bing(void) { // a function that defined the number of elements
+    order=23118;
+    ptr=ding;
+}
+
+void beep (void) { // a function responsible of creating sound
+
+    if (order) {
+        /********************************************************
+         * this part is converting sined values to unsigned     *
+         * so as to make the sound clear                        *
+         ********************************************************/
+        a=*ptr;
+        ptr++;
+        b=a;
+        c= (unsigned short)b;
+        beeper=c;
+        if (--order==0) // when the beeping is finish a new event will be called (timeout)
+            new_event(timeout);
+    }
+}
+
+void bing_start (void) { // a ticker function for the beeper.
+    beeper=0;
+    order=0;
+    bing_timer.attach_us(&beep,23); // repeatedly call "beep" function.
+}
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