Diff: main.cpp

Revision:

0:4912234b4155

Child:

1:93d2771b8797

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Oct 21 08:41:14 2014 +0000
@@ -0,0 +1,44 @@
+//--------------------------------------------------------------
+// FIR フィルタ，係数の対称性を利用する構造
+//      Analog Input : A0
+//      Analog Output: MCP4922 using SPI
+// 2014/10/21, Copyright (c) 2014 MIKAMI, Naoki
+//--------------------------------------------------------------
+
+#include "mbed.h"
+
+#include "ADC_Interrupt.hpp"    // for ADC using interrupt
+#include "DAC_MCP4922.hpp"      // for DAC MCP4922
+#include "ScfClockTim3.hpp"     // for clock supplied to SCF
+#include "Coefficients_200_LPF_Sym.hpp"
+
+using namespace Mikami;
+
+const int FS_ = 12000;          // Sampling frequency: 12 kHz
+ADC_Base adc_(A0, FS_);                 // for AD
+DAC_MCP4922 myDac_(DAC_MCP4922::DAC_A); // for DA
+
+int main()
+{
+    ScfClockTim3(500000);       // cutoff frequency: 5 kHz
+
+    float xn[ORDER_+1];
+    for (int n=0; n<=ORDER_; n++)
+        xn[n] = 0;
+    
+    while (true)
+    {
+        xn[0] = adc_.Read();     // Read from A0
+        //-----------------------------------------------
+
+        float yn = hm_[ORDER_/2]*xn[ORDER_/2];
+        for (int k=0; k<ORDER_/2; k++)
+            yn = yn + hm_[k]*(xn[k] + xn[ORDER_-k]);
+
+        for (int k=ORDER_; k>0; k--)
+            xn[k] = xn[k-1];  // move input signals
+
+        //-----------------------------------------------
+        myDac_.Write(yn);    // Write to DAC
+    }
+}