CQpub0 Mikami
The experiment using this program is introduced on "Interface" No.12, CQ publishing Co.,Ltd, 2014. 本プログラムを使った実験は，CQ出版社のインターフェース 2014年12月号で紹介しています．
Dependencies: DSProcessingIO mbed
Diff: FIR_LPF_Direct.cpp
- Revision:
- 0:b811ec8a7e8a
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/FIR_LPF_Direct.cpp Tue Jul 15 08:45:04 2014 +0000
@@ -0,0 +1,44 @@
+//--------------------------------------------------------------
+// FIR filter: Even order, Direct form
+//
+// Copyright (c) 2014 MIKAMI, Naoki, 2014/07/15
+//--------------------------------------------------------------
+
+#include "mbed.h"
+#include "AdcInternal.hpp"
+#include "MCP4922Single.hpp"
+#include "coefficients_200.hpp"
+#include "FIR_Direct.hpp"
+
+using namespace Mikami;
+
+// sampling frequency
+const float FS_ = 10.0e3f;
+
+// for AD converter
+Adc adc_(A0);
+// for DA converter
+Dac dacA_(Dac::DAC_A);
+
+Ticker timer_; // for timer interrupt
+DigitalOut pinD8_(D8); // for measurement of execution time
+
+FirDirect<ORDER_> lpf(hm_);
+
+// Called every 0.1 ms
+void TimerIsr()
+{
+ float xn = adc_.Read(); // input
+
+ // Execute FIR filter
+ float yn = lpf.Execute(xn);
+
+ dacA_.Write(yn); // output
+}
+
+int main()
+{
+ timer_.attach_us(&TimerIsr, 1.0e6f/FS_);
+
+ while (true) {} // infinite loop
+}