Revision 2:77c859f607ac, committed 2014-12-09

Comitter:

sjsm3

Date:

Tue Dec 09 13:43:26 2014 +0000

Parent:

1:7ea05d050158

Commit message:

added speaker functionality

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Speaker.h	Tue Dec 09 13:43:26 2014 +0000
@@ -0,0 +1,51 @@
+class Speaker
+{
+public:
+    Speaker(PinName pin) : _pin(pin) {
+// _pin(pin) means pass pin to the Speaker Constructor
+// precompute 32 sample points on one sine wave cycle
+// used for continuous sine wave output later
+        for(int k=0; k<32; k++) {
+            Analog_out_data[k] = int (65536.0 * ((1.0 + sin((float(k)/32.0*6.28318530717959)))/2.0));
+            // scale the sine wave to 16-bits - as needed for AnalogOut write_u16 arg
+        }
+ 
+    }
+// class method to play a note based on AnalogOut class
+    void PlayNote(float frequency, float duration, float volume) {
+        // scale samples using current volume level arg
+        for(int k=0; k<32; k++) {
+            Analog_scaled_data[k] = Analog_out_data[k] * volume;
+        }
+        // reset to start of sample array
+        i=0;
+        // turn on timer interrupts to start sine wave output
+        Sample_Period.attach(this, &Speaker::Sample_timer_interrupt, 1.0/(frequency*32.0));
+        // play note for specified time
+        wait(duration);
+        // turns off timer interrupts
+        Sample_Period.detach();
+        // sets output to mid range - analog zero
+        this->_pin.write_u16(32768);
+ 
+    }
+private:
+// sets up specified pin for analog using AnalogOut class
+    AnalogOut _pin;
+    // set up a timer to be used for sample rate interrupts
+    Ticker Sample_Period;
+ 
+    //variables used by interrupt routine and PlayNote
+    volatile int i;
+    short unsigned Analog_out_data[32];
+    short unsigned Analog_scaled_data[32];
+ 
+// Interrupt routine
+// used to output next analog sample whenever a timer interrupt occurs
+    void Sample_timer_interrupt(void) {
+        // send next analog sample out to D to A
+        this->_pin.write_u16(Analog_scaled_data[i]);
+        // increment pointer and wrap around back to 0 at 32
+        i = (i+1) & 0x01F;
+    }
+};
\ No newline at end of file

--- a/main.cpp	Mon Dec 08 20:31:02 2014 +0000
+++ b/main.cpp	Tue Dec 09 13:43:26 2014 +0000
@@ -1,11 +1,12 @@
 #include "mbed.h"
 #include <string>
 #include <vector>
+#include "Speaker.h"
 
 // These are used for setting the serial buffer size and how long the mbed should wait between updates
 static const float SLEEP_TIME = 0.5;    // x86 background process will only have updates every 1 second in ideal situations
 static const float PIN_DELAY = 0.05;   // the time to wait for allowing the relays to fully cycle between transitions
-static const float POWER_UP_TIME = 5.0; // seconds for the device clicker to go from an OFF to ON state
+static const float POWER_UP_TIME = 0; // seconds for the device clicker to go from an OFF to ON state
 static const int NUM_CMDS = 8;
 
 // Used for signaling to the main loop if new serial data has arrived by the serial rx interrupt
@@ -23,6 +24,12 @@
 // Global string for storing the received serial data on the serial rx interrupt
 string gStr;
 
+Speaker mySpeaker(p18);
+//AnalogOut DACout(p18);
+//wave_player waver(&DACout);
+//LocalFileSystem local("local");
+//FILE *wave_file;
+
 
 void rx_interrupt(void)
 {
@@ -93,6 +100,8 @@
     commands[5] = "clickerC\n";
     commands[6] = "clickerD\n";
     commands[7] = "clickerE\n";
+    
+    //wave_file = fopen("/local/p.wav","r");
 
     // Initialize all relays to off state
     for (int i=0; i<6; i++)
@@ -151,7 +160,11 @@
                     break;
 
                 case 3:  // sayHere
-                    pc.printf("    Audio currently unsupported\r\n");
+                    pc.printf("    Audio playing...\r\n");
+                    mySpeaker.PlayNote(969.0,1.5,1.0);
+                    //wave_file=fopen("/local/P.WAV","r");
+                    //waver.play(wave_file);
+                    //fclose(wave_file);
                     break;
 
                 case 4: // clickerA