CQpub0 Mikami
The experiment using this program is introduced on "Interface" No.3, CQ publishing Co.,Ltd, 2015. 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 2015年3月号で紹介しています．
Dependencies: DSProcessingIO mbed
Revision 0:47656a949b95, committed 2014-07-15
- Comitter:
- CQpub0Mikami
- Date:
- Tue Jul 15 09:26:17 2014 +0000
- Child:
- 1:4fa3cb574a57
- Commit message:
- 1
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/DSProcessingIO.lib Tue Jul 15 09:26:17 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/CQpub0Mikami/code/DSProcessingIO/#c3f647a89947
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Echo.cpp Tue Jul 15 09:26:17 2014 +0000
@@ -0,0 +1,46 @@
+//--------------------------------------------------------------
+// Echo generation system
+// Copyright (c) 2014 MIKAMI, Naoki, 2014/06/28
+//--------------------------------------------------------------
+
+#include "mbed.h"
+#include "AdcInternal.hpp"
+#include "MCP4922Single.hpp"
+#include "ReverbUnit.hpp"
+
+using namespace Mikami;
+
+const float FS_ = 10.0e3f;
+Adc adc_(A0);
+Dac dac_(Dac::DAC_A);
+
+Ticker timer_; // for timer interrupt
+
+const float G_C_ = 0.8f;
+const float G_A_ = 0.6f;
+const float G0_ = 1.0f - G_C_;
+CombFilter<887> cmF1(G_C_);
+CombFilter<1153> cmF2(G_C_);
+CombFilter<1499> cmF3(G_C_);
+AllPassFilter<97> apF1(G_A_);
+AllPassFilter<131> apF2(G_A_);
+
+void TimerIsr()
+{
+ float xn = adc_.Read(); // input
+
+ xn = G0_*xn;
+ float yn = cmF1.Execute(xn) + cmF2.Execute(xn)
+ + cmF3.Execute(xn);
+ yn = apF2.Execute(apF1.Execute(yn));
+ yn = yn + xn; // add direct input signal
+
+ dac_.Write(yn); // output
+}
+
+int main()
+{
+ timer_.attach_us(&TimerIsr, 1.0e6f/FS_);
+ while (true) {} // infinite loop
+}
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/ReverbUnit.hpp Tue Jul 15 09:26:17 2014 +0000
@@ -0,0 +1,78 @@
+//--------------------------------------------------------------
+// Reverb unit
+// Copyright (c) 2014 MIKAMI, Naoki, 2014/06/28
+//--------------------------------------------------------------
+
+#ifndef REVERB_UNIT_HPP
+#define REVERB_UNIT_HPP
+
+#include "mbed.h"
+
+namespace Mikami
+{
+ // Base class for reverb unit
+ template<int delay> class Reverb
+ {
+ private:
+ int ptr_;
+ float un_[delay]; // for delay
+
+ Reverb(const Reverb&);
+ Reverb& operator=(const Reverb&);
+ protected:
+ float Get() { return un_[ptr_]; }
+ void Set(float x)
+ {
+ un_[ptr_] = x;
+ if (++ptr_ >= delay) ptr_ = 0;
+ }
+ public:
+ // Constructor
+ Reverb() : ptr_(0) { Clear(); }
+
+ // Execute of filter (pure virtual function)
+ virtual float Execute(float x) = 0;
+
+ // Clear internal delay elements
+ void Clear()
+ { for (int n=0; n<delay; n++) un_[n] = 0; }
+ };
+
+ // Reverb unit using comb filter
+ template<int delay> class CombFilter : public Reverb<delay>
+ {
+ private:
+ const float G0_;
+ public:
+ // Constructor
+ CombFilter(float g) : G0_(g) {}
+
+ // Execute comb filter
+ virtual float Execute(float x)
+ {
+ float yn = Reverb<delay>::Get();
+ Reverb<delay>::Set(x + G0_*yn);
+ return yn;
+ }
+ };
+
+ // Reverb unit using allpass filter
+ template<int delay> class AllPassFilter : public Reverb<delay>
+ {
+ private:
+ const float G0_;
+ public:
+ // Constructor
+ AllPassFilter(float g) : G0_(g) {}
+
+ // Execute allpass filter
+ virtual float Execute(float x)
+ {
+ float un = x + G0_*Reverb<delay>::Get();
+ float yn = -G0_*un + Reverb<delay>::Get();
+ Reverb<delay>::Set(un);
+ return yn;
+ }
+ };
+}
+#endif // REVERB_UNIT_HPP
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Tue Jul 15 09:26:17 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/04dd9b1680ae \ No newline at end of file