Kenji Arai / Mbed OS CW_Decoder_using_FFT_on_F446

CW Decoder (Morse code decoder) 1st release version. Only run on Nucleo-F446RE mbed board.

Dependencies:   Array_Matrix F446_AD_DA ST7565_SPI_LCD TextLCD UIT_FFT_Real

Fork of F446_MySoundMachine by 不韋 呂

Base on F446_MySoundMachine program created by 不韋 呂-san.
Thanks to 不韋 呂-san making fundamental part such as FFT and ADC high speed interrupt driven program.
I just combined LCD and show CW code.

Diff: MySpectrogram/Hamming.hpp

Revision:
6:5e21ac9f0550
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MySpectrogram/Hamming.hpp	Sun Feb 05 08:02:54 2017 +0000
@@ -0,0 +1,48 @@
+//-------------------------------------------------------------------
+//  Hamming windowing with zero-padding
+//
+//  2016/07/23, Copyright (c) 2016 MIKAMI, Naoki
+//-------------------------------------------------------------------
+
+#ifndef HAMMING_WINDOW_HPP
+#define HAMMING_WINDOW_HPP
+
+#include "mbed.h"
+#include "Array.hpp"
+
+namespace Mikami
+{
+    class HammingWindow
+    {
+    public:
+        // Constructor
+        HammingWindow(uint16_t nData, uint16_t nFft)
+                : N_(nData), NFFT_(nFft), w_(nData)
+        {
+            float pi2L = 6.283185f/(float)nData;
+            for (int k=0; k<nData; k++)
+                w_[k] = 0.54f - 0.46f*cosf(k*pi2L);
+        }
+        
+        // Destructor
+        virtual ~HammingWindow() {}
+        
+        // Windowing
+        void Execute(const float x[], float y[])
+        {
+            for (int n=0; n<N_; n++) y[n] = x[n]*w_[n];
+            for (int n=N_; n<NFFT_; n++) y[n] = 0;
+        }
+
+    private:
+        const int N_;
+        const int NFFT_;
+                
+        Array<float> w_;
+
+        // disallow copy constructor and assignment operator
+        HammingWindow(const HammingWindow& );
+        HammingWindow& operator=(const HammingWindow& );
+    };
+}
+#endif  // HAMMING_WINDOW_HPP