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| author | Yann Herklotz <ymherklotz@gmail.com> | 2017-05-10 13:17:31 +0100 |
|---|---|---|
| committer | Yann Herklotz <ymherklotz@gmail.com> | 2017-05-10 13:17:31 +0100 |
| commit | aa30a51f3e2d9120aa819c1bc8162793662ccf32 (patch) | |
| tree | e7659204b1ecf3f65fae106c12b096fd552c2d8d /main.cpp | |
| download | WaveGenerator-aa30a51f3e2d9120aa819c1bc8162793662ccf32.tar.gz WaveGenerator-aa30a51f3e2d9120aa819c1bc8162793662ccf32.zip | |
Adding initial files
Diffstat (limited to 'main.cpp')
| -rw-r--r-- | main.cpp | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/main.cpp b/main.cpp new file mode 100644 index 0000000..8132692 --- /dev/null +++ b/main.cpp @@ -0,0 +1,260 @@ +#include "mbed.h"
+#include "Adafruit_SSD1306.h"
+
+//Switch input definition
+#define PIN21 p21
+#define PIN22 p22
+#define PIN23 p23
+#define PIN24 p24
+//#define PIN18 p25
+#define PIN18 p18
+
+//Sampling period for the switch oscillator (us)
+#define SW_PERIOD 20000
+#define LOW_PERIOD 100
+
+//Display interface pin definitions
+#define D_MOSI_PIN p5
+#define D_CLK_PIN p7
+#define D_DC_PIN p8
+#define D_RST_PIN p9
+#define D_CS_PIN p10
+
+//an SPI sub-class that sets up format and clock speed
+class SPIPreInit : public SPI
+{
+public:
+ SPIPreInit(PinName mosi, PinName miso, PinName clk) : SPI(mosi,miso,clk)
+ {
+ format(8,3);
+ frequency(2000000);
+ };
+};
+
+//Interrupt Service Routine prototypes (functions defined below)
+void sedge1();
+void sedge2();
+void sedge3();
+void sedge4();
+void tout();
+void checkButtonInput();
+void select();
+void m_abort();
+void increment();
+void gen_square(uint16_t avg1_threshold);
+void gen_wave();
+void gen_sine();
+
+//Output for the alive LED
+DigitalOut alive(LED1);
+DigitalOut ind(LED4);
+DigitalOut square(p17);
+AnalogOut aout(p18);
+PwmOut pwm_pin(p25);
+
+//External interrupt input from the switch oscillator
+InterruptIn p_21(PIN21);
+InterruptIn p_22(PIN22);
+InterruptIn p_23(PIN23);
+InterruptIn p_24(PIN24);
+
+//Switch sampling timer
+Ticker swtimer;
+Ticker tck;
+
+//Registers for the switch counter, switch counter latch register and update flag
+volatile uint16_t scounter1=0;
+volatile uint16_t scount1=0;
+volatile uint16_t scounter2=0;
+volatile uint16_t scount2=0;
+volatile uint16_t scounter3=0;
+volatile uint16_t scount3=0;
+volatile uint16_t scounter4=0;
+volatile uint16_t scount4=0;
+volatile uint16_t update=0;
+volatile uint16_t value=0;
+volatile uint16_t counter=0;
+
+volatile uint32_t frequency=0;
+
+//Initialise SPI instance for communication with the display
+SPIPreInit gSpi(D_MOSI_PIN,NC,D_CLK_PIN); //MOSI,MISO,CLK
+
+//Initialise display driver instance
+Adafruit_SSD1306_Spi gOled1(gSpi,D_DC_PIN,D_RST_PIN,D_CS_PIN,64,128); //SPI,DC,RST,CS,Height,Width
+
+
+const double pi = 3.141592653589793238462;
+const double amplitude = 0.5f;
+const double offset = 65535/2;
+double rads = 0.0;
+uint16_t sample = 0;
+
+int main() {
+ //Initialisation
+ gOled1.setRotation(2); //Set display rotation
+
+ //Attach switch oscillator counter ISR to the switch input instance for a rising edge
+ p_21.rise(&sedge1);
+ p_22.rise(&sedge2);
+ p_23.rise(&sedge3);
+ p_24.rise(&sedge4);
+
+ //Attach switch sampling timer ISR to the timer instance with the required period
+ swtimer.attach_us(&tout, SW_PERIOD);
+ tck.attach_us(&gen_wave, LOW_PERIOD);
+ pwm_pin.period(0.000001);
+
+ gOled1.clearDisplay();
+
+ //Main loop
+ while(1)
+ {
+ //Has the update flag been set?
+ if (update) {
+ //Clear the update flag
+ update = 0;
+
+ gOled1.setTextCursor(0, 0);
+
+ checkButtonInput();
+ gOled1.printf("freq = %10u Hz\n",frequency);
+ gOled1.printf("T = %10u us",(unsigned)(1/(float)frequency*1000000));
+
+ //Copy the display buffer to the display
+ gOled1.display();
+
+ //Toggle the alive LED
+ alive = !alive;
+ }
+ gen_sine();
+ //wait(0.15);
+ }
+}
+
+
+//Interrupt Service Routine for rising edge on the switch oscillator input
+void sedge1() {
+ //Increment the edge counter
+ scounter1++;
+}
+
+void sedge2() {
+ //Increment the edge counter
+ scounter2++;
+}
+
+void sedge3() {
+ //Increment the edge counter
+ scounter3++;
+}
+
+void sedge4() {
+ //Increment the edge counter
+ scounter4++;
+}
+
+//Interrupt Service Routine for the switch sampling timer
+void tout() {
+ //Read the edge counter into the output register
+ scount1 = scounter1;
+ scount2 = scounter2;
+ scount3 = scounter3;
+ scount4 = scounter4;
+ //Reset the edge counter
+ scounter1 = 0;
+ scounter2 = 0;
+ scounter3 = 0;
+ scounter4 = 0;
+ //Trigger a display update in the main loop
+ update = 1;
+}
+
+void checkButtonInput()
+{
+ ind=0;
+
+ static volatile const uint16_t AVG1=scount1;
+ static volatile const uint16_t AVG2=scount2;
+ static volatile const uint16_t AVG3=scount3;
+ static volatile const uint16_t AVG4=scount4;
+
+ float threshold=0.97;
+
+ if(scount1<AVG1*threshold)// && scount2>=AVG2*threshold && scount3>=AVG3*threshold && scount4>=AVG4*threshold)
+ {
+ //m_abort();
+ ind=1;
+ }
+
+ if(scount2<AVG2*threshold)// && scount1>=AVG1*threshold && scount3>=AVG3*threshold && scount4>=AVG4*threshold)
+ {
+ //gen_square(AVG1*threshold);
+ ind=1;
+ }
+
+ if(scount3<AVG3*threshold)// && scount2>=AVG2*threshold && scount1>=AVG1*threshold && scount4>=AVG4*threshold)
+ {
+ select();
+ ind=1;
+ }
+
+ if(scount4<AVG4*threshold)// && scount2>=AVG2*threshold && scount3>=AVG3*threshold && scount1>=AVG1*threshold)
+ {
+ increment();
+ ind=1;
+ }
+}
+
+void select()
+{
+ frequency*=10;
+}
+
+void m_abort()
+{
+ frequency=0;
+}
+
+void increment()
+{
+ if(frequency%10==9)
+ frequency=frequency-9;
+ else
+ ++frequency;
+}
+
+
+void gen_square(uint16_t avg1_threshold)
+{
+ for(;; wait_us((unsigned)(1/(float)frequency*1000000)/2))
+ {
+ //square=!square;
+
+ if(scount1<avg1_threshold)
+ {
+ m_abort();
+ break;
+ }
+ }
+}
+
+void gen_wave()
+{
+ if(counter*LOW_PERIOD>=(unsigned)1/(float)frequency*500000)
+ {
+ value=!value;
+ pwm_pin.write(value);
+ counter=0;
+ }
+ counter++;
+}
+
+void gen_sine()
+{
+ for (int i = 0; i < 360; i++) {
+ rads = (pi * i) / 180.f;
+ sample = (uint16_t)(amplitude * (offset * (cos(rads*2 + pi))) + offset);
+ aout.write_u16(sample);
+ }
+}
\ No newline at end of file |