Diff: Speaker.h

Revision:

12:730a95b81992

Parent:

11:68194bd43e0b

--- a/Speaker.h	Wed Dec 16 15:05:27 2020 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,52 +0,0 @@
-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;
-    }
-};
-