Diff: main.cpp

Revision:

0:0fa4ebf14d9c

Child:

1:37130d7a175f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Dec 14 21:12:07 2018 +0000
@@ -0,0 +1,86 @@
+#include "mbed.h"
+#include "LCD_DISCO_F429ZI.h"
+
+AnalogOut pinout(PA_4);
+LCD_DISCO_F429ZI lcd;
+
+#define PI        (3.141592653589793238462)
+#define AMPLITUDE (1.0)    // x * 3.3V
+#define PHASE     (PI * 1) // 2*pi is one period
+#define RANGE     (0x7FFF)
+#define OFFSET    (0x7FFF)
+
+#define PERIOD    (70000)
+
+// Configuration for sinewave output
+#define BUFFER_SIZE (360)
+uint16_t buffer[BUFFER_SIZE];
+uint8_t text[30];
+int x = 0;
+
+InterruptIn user_button(USER_BUTTON);
+
+void button_pressed(){
+    x = (x+1)%4;
+}
+
+void calculate_sinewave(void);
+
+int main() {
+    calculate_sinewave();
+    while(1) {
+        user_button.rise(&button_pressed);      
+        switch(x){
+            // sinewave output
+            case 0:
+                for (int i = 0; i < BUFFER_SIZE; i++) {
+                    pinout.write_u16(buffer[i]);
+                }
+                break;
+            
+            // triangle output
+            case 1:
+                for (int i = 0; i < PERIOD/2; i++) {
+                    pinout.write_u16(i);
+                }
+                
+                for (int i = PERIOD/2; i>0; i--) {
+                    pinout.write_u16(i);
+                }
+                break;
+            
+            //square output
+            case 2:
+                for (int i = 0; i < PERIOD/2; i++) {
+                    pinout.write_u16(0);
+                }
+                
+                for (int i = PERIOD/2; i>0; i--) {
+                    pinout.write_u16((uint16_t)(AMPLITUDE*RANGE+OFFSET));
+                }       
+                break;
+            
+            case 3:
+                //sawtooth output
+                for (int i = 0; i < PERIOD/2; i++) {
+                    pinout.write_u16(i);
+                }
+                
+                for (int i = PERIOD/2; i>0; i--) {
+                    pinout.write_u16(0);
+                }
+                break;
+                
+            default:
+                lcd.DisplayStringAt(0, LINE(1), (uint8_t *)"Signal Generator", CENTER_MODE);
+        }
+    }
+}
+
+// Create the sinewave buffer
+void calculate_sinewave(void){
+  for (int i = 0; i < BUFFER_SIZE; i++) {
+     double rads = (PI * i)/180.0; // Convert degree in radian
+     buffer[i] = (uint16_t)(AMPLITUDE * (RANGE * (cos(rads + PHASE))) + OFFSET);
+  }
+}