Diff: MIDISpeaker.h

Revision:

2:5366ce17fe55

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MIDISpeaker.h	Wed Dec 13 03:31:09 2017 +0000
@@ -0,0 +1,44 @@
+#include "mbed.h"
+#include "uLCD_4DGL.h"
+
+#define BAUD_9600    312
+// new class to play a note on Speaker based on PwmOut class
+uLCD_4DGL uLCD(p9,p10,p11);
+int x1;
+int y1;
+class MIDISpeaker
+{
+public:
+    MIDISpeaker(PinName pin) : _pin(pin) {
+// _pin(pin) means pass pin to the Speaker Constructor
+    }
+// class method to play a note based on PwmOut class
+    void PlayNote(unsigned char note, unsigned char velocity) {//volatile int duration) {
+        int notef = int(note); //convert note to int
+        int velocityf = int(velocity); //convert velocity to int
+        double noteg = double(notef); //convert note to double
+        double velocityg = double(velocityf); //convert velocity to double
+        double f_n = double((noteg - 49)/12); //use piano frequency formula to find corresponding frequency
+        double freq = (pow(2, f_n)) * 440;
+        _pin.period(1.0/freq); //use frequency to set period of pwmout pin
+        velocityg = ((velocityg/127.0) * 0.5); //calculate volume of note and set to pwmout pin
+        _pin = velocityg;
+        x1 = ((freq/4000)*115) + 5; //calcuate starting position for frequency spectrum [0,4000 Hz]
+        y1 = 110 - ((_pin/0.5)*105); // calculate magnitude of spectrum based on velocity
+        uLCD.locate(0,13);
+        uLCD.printf("\nkey: %d, freq: %4.0f, volume: %.2f\n", note, freq, velocityg);
+        uLCD.textbackground_color(BLUE);
+        uLCD.filled_rectangle(x1, y1, x1+2, 109, BLACK);
+    }
+    void StopNote() {
+        _pin = 0.0;
+        //uLCD.filled_rectangle(x1, y1, x1+2, 109, BLUE); //code to clear rectangle from lcd
+    }
+    
+private:
+// sets up specified pin for PWM using PwmOut class 
+    PwmOut _pin;
+};
+ 
+// Speaker test program - earlier euro police style siren now using new class method
+//
\ No newline at end of file