不韋 呂 / Mbed 2 deprecated F746_RealtimeSpectrumAnalyzer

Realtime spectrum analyzer. Using FFT, linear prediction, or cepstrum smoothing. Version using MEMS microphone and CODEC, named "F746_RealtimeSpectrumAnalyzer_MEMS_Mic" is registered. リアルタイム スペクトル解析器．解析の手法：FFT，線形予測法，ケプストラムによる平滑化の３種類．このプログラムの説明は，CQ出版社のインターフェース誌，2016年4月号に掲載．外付けのマイクまたは他の信号源等を A0 に接続する．線形予測法，ケプストラムは，スペクトル解析の対象を音声信号に想定してパラメータを設定している．MEMS マイクと CODEC を使ったバージョンを "F746_RealtimeSpectrumAnalyzer_MEMS_Mic" として登録．

Dependencies:   BSP_DISCO_F746NG BUTTON_GROUP LCD_DISCO_F746NG TS_DISCO_F746NG UIT_FFT_Real mbed

MyClasses/Sampler.cpp@18:6630d61aeb3c, 2016-02-22 (annotated)

Committer:
MikamiUitOpen
Date:
Mon Feb 22 13:54:51 2016 +0000
Revision:
18:6630d61aeb3c
Parent:
12:e5367ab82460 
19

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 2:095b360e0f54 1 //-----------------------------------------------------------
MikamiUitOpen 2:095b360e0f54 2 // Class for sampling input signal
MikamiUitOpen 2:095b360e0f54 3 //
MikamiUitOpen 8:1f4bc859bc84 4 // 2015/12/28, Copyright (c) 2015 MIKAMI, Naoki
MikamiUitOpen 2:095b360e0f54 5 //-----------------------------------------------------------
MikamiUitOpen 2:095b360e0f54 6
MikamiUitOpen 2:095b360e0f54 7 #include "Sampler.hpp"
MikamiUitOpen 2:095b360e0f54 8
MikamiUitOpen 2:095b360e0f54 9 namespace Mikami
MikamiUitOpen 2:095b360e0f54 10 {
MikamiUitOpen 7:6598a9b70e5a 11 Sampler::Sampler(PinName pin, int fs, int nData)
MikamiUitOpen 2:095b360e0f54 12 : TS_(1000000/fs), N_DATA_(nData), aIn_(pin),
MikamiUitOpen 8:1f4bc859bc84 13 sn_(new int16_t[nData]),
MikamiUitOpen 7:6598a9b70e5a 14 buffer_(new int16_t[nData])
MikamiUitOpen 7:6598a9b70e5a 15 {
MikamiUitOpen 8:1f4bc859bc84 16 for (int n=0; n<nData; n++) sn_[n] = 32767;
MikamiUitOpen 2:095b360e0f54 17 }
MikamiUitOpen 2:095b360e0f54 18
MikamiUitOpen 7:6598a9b70e5a 19 Sampler::~Sampler()
MikamiUitOpen 7:6598a9b70e5a 20 {
MikamiUitOpen 8:1f4bc859bc84 21 delete[] sn_;
MikamiUitOpen 7:6598a9b70e5a 22 delete[] buffer_;
MikamiUitOpen 7:6598a9b70e5a 23 }
MikamiUitOpen 7:6598a9b70e5a 24
MikamiUitOpen 8:1f4bc859bc84 25 // Start sampling
MikamiUitOpen 8:1f4bc859bc84 26 void Sampler::Start(bool onOff)
MikamiUitOpen 2:095b360e0f54 27 {
MikamiUitOpen 2:095b360e0f54 28 count_ = 0;
MikamiUitOpen 7:6598a9b70e5a 29 filled_ = false;
MikamiUitOpen 2:095b360e0f54 30 trigger_ = false;
MikamiUitOpen 2:095b360e0f54 31 xnM1_ = 32767;
MikamiUitOpen 8:1f4bc859bc84 32 Invert(onOff);
MikamiUitOpen 8:1f4bc859bc84 33 timer_.attach_us(this, &Sampler::Isr, TS_);
MikamiUitOpen 2:095b360e0f54 34 }
MikamiUitOpen 2:095b360e0f54 35
MikamiUitOpen 2:095b360e0f54 36 // Interrupt service routine for Ticker
MikamiUitOpen 2:095b360e0f54 37 void Sampler::Isr()
MikamiUitOpen 2:095b360e0f54 38 {
MikamiUitOpen 8:1f4bc859bc84 39 int16_t xn = (this->*Rd)(); // Read from A0
MikamiUitOpen 2:095b360e0f54 40 if (!trigger_)
MikamiUitOpen 2:095b360e0f54 41 {
MikamiUitOpen 2:095b360e0f54 42 // Detect rising edge
MikamiUitOpen 2:095b360e0f54 43 if ((xn > (xnM1_+512)) && (xn > 2048))
MikamiUitOpen 2:095b360e0f54 44 trigger_ = true;
MikamiUitOpen 2:095b360e0f54 45 else
MikamiUitOpen 2:095b360e0f54 46 xnM1_ = xn;
MikamiUitOpen 2:095b360e0f54 47 return;
MikamiUitOpen 2:095b360e0f54 48 }
MikamiUitOpen 8:1f4bc859bc84 49 else
MikamiUitOpen 8:1f4bc859bc84 50 buffer_[count_] = xn;
MikamiUitOpen 2:095b360e0f54 51
MikamiUitOpen 2:095b360e0f54 52 if (++count_ >= N_DATA_)
MikamiUitOpen 7:6598a9b70e5a 53 {
MikamiUitOpen 7:6598a9b70e5a 54 timer_.detach();
MikamiUitOpen 8:1f4bc859bc84 55 memcpy(sn_, buffer_, N_DATA_*sizeof(int16_t));
MikamiUitOpen 8:1f4bc859bc84 56 filled_ = true; // Permits spectrum analysis
MikamiUitOpen 7:6598a9b70e5a 57 }
MikamiUitOpen 2:095b360e0f54 58 }
MikamiUitOpen 2:095b360e0f54 59 }