Diff: main.cpp

Revision:

0:697cc11ace92

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sun Dec 29 01:13:41 2013 +0000
@@ -0,0 +1,46 @@
+/*
+ * Demonstrates sending a buffer repeatedly to the DAC using DMA.
+ * Connect an oscilloscope to Mbed pin 18.
+ */
+
+#include "mbed.h"
+#include "DMAFuncGen.h"
+
+AnalogIn ain(p17);
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+DigitalOut led3(LED3);
+DigitalOut led4(LED4);
+
+MODDMA dma;
+DMAFuncGen fg(dma, MODDMA::Channel_0);
+
+int main() {
+    wait(0.5);
+   
+    // Create waveform.
+    fg.buffer_size=400;
+    fg.buffer = new uint32_t[fg.buffer_size];
+    const float PI = 3.1415927;
+    for (int i=0; i<fg.buffer_size; i++) {
+        int x = (511*sin(2*PI*i/fg.buffer_size)) +512;
+        fg.set(i,x << 6);
+    }
+    
+    fg.Connect();
+    fg.Setup();
+    fg.SetFrequency(0.5);
+    printf("Frequency: %f\r\n",fg.Frequency());
+    fg.Start();
+    
+    // Simple oscilloscope, using the LEDs -
+    // Connect pin 18 (DAC) to p17 (ADC) for it to work.
+    float z;
+    while (1){
+        z=ain.read();
+        led1 = (z > 0.2) ? 1 : 0;
+        led2 = (z > 0.4) ? 1 : 0;
+        led3 = (z > 0.6) ? 1 : 0;
+        led4 = (z > 0.8) ? 1 : 0;
+    }
+}