Diff: main.cpp

Revision:

0:b26f86125165

Child:

2:a19243a20882

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Oct 30 00:38:14 2014 +0000
@@ -0,0 +1,64 @@
+//--------------------------------------------------------------
+// 移動平均, 平均数：1, 2, 4, 8, 16, 32, 64：スイッチで選択
+// スイッチの状態を printf() で表示する
+//      Analog Input : A0
+//      Analog Output: MCP4922 using SPI
+// 2014/10/30, 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
+
+using namespace Mikami;
+
+const int FS_ = 12000;  // Sampling frequency: 12 kHz
+ADC_Intr adc_(A0, FS_); // for AD using interrupt
+DAC_MCP4922 myDac_;     // for DA
+
+DigitalIn sw1_(D2, PullDown);
+DigitalIn sw2_(D3, PullDown);
+DigitalIn sw4_(D4, PullDown);
+DigitalIn sw8_(D5, PullDown);
+
+const int M_ = 64;  // Maximum of average count
+float xn_[M_];
+volatile int nAv_;  // "volatile": to make sure
+
+// Interrupt service routine for ADC
+void AdcIsr()
+{   
+    xn_[0] = adc_.Read();   // Read from A0
+    //-----------------------------------------------
+
+    float yn = 0;
+    for (int k=0; k<nAv_; k++) yn = yn + xn_[k];
+    yn = yn/(float)nAv_;    // yn: average
+
+    // Update input buffer
+    for (int k = nAv_-1; k>0; k--)
+        xn_[k] = xn_[k-1];
+
+    //-----------------------------------------------
+    myDac_.Write(yn);       // Write to DAC
+}
+
+int main()
+{
+    ScfClockTim3(500000);       // cutoff frequency: 5 kHz
+    adc_.SetIntrVec(AdcIsr);    // Assign ISR for ADC interrupt
+
+    for (int n=0; n<M_; n++) xn_[n] = 0;
+    
+    while (true)
+    {
+        int sw = (sw8_ << 3) | (sw4_ << 2) | (sw2_ << 1) | sw1_;
+        nAv_ = 1 << sw;
+        if (nAv_ > 64) nAv_ = 64;       
+        printf("\r\nnAv = %d, sw = %d", nAv_, sw);
+
+        wait(0.5f);
+    }
+}