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@2:095b360e0f54, 2015-12-13 (annotated)

Committer:
MikamiUitOpen
Date:
Sun Dec 13 07:20:14 2015 +0000
Revision:
2:095b360e0f54
Child:
5:98ec9dd54144
3

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 2:095b360e0f54 4 // 2015/12/11, 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 2:095b360e0f54 11 Sampler::Sampler(PinName pin, int fs, int nData)
MikamiUitOpen 2:095b360e0f54 12 : TS_(1000000/fs), N_DATA_(nData), aIn_(pin),
MikamiUitOpen 2:095b360e0f54 13 buffer_(new int16_t[nData])
MikamiUitOpen 2:095b360e0f54 14 {
MikamiUitOpen 2:095b360e0f54 15 Set(false);
MikamiUitOpen 2:095b360e0f54 16 Rd[0] = &Sampler::ReadNorm; // inphase
MikamiUitOpen 2:095b360e0f54 17 Rd[1] = &Sampler::ReadInv; // out-of-phase
MikamiUitOpen 2:095b360e0f54 18 sw_ = 0;
MikamiUitOpen 2:095b360e0f54 19 }
MikamiUitOpen 2:095b360e0f54 20
MikamiUitOpen 2:095b360e0f54 21 void Sampler::IntrEnable()
MikamiUitOpen 2:095b360e0f54 22 {
MikamiUitOpen 2:095b360e0f54 23 count_ = 0;
MikamiUitOpen 2:095b360e0f54 24 timer_.attach_us(this, &Sampler::Isr, TS_);
MikamiUitOpen 2:095b360e0f54 25 }
MikamiUitOpen 2:095b360e0f54 26
MikamiUitOpen 2:095b360e0f54 27 void Sampler::Set(bool tf)
MikamiUitOpen 2:095b360e0f54 28 {
MikamiUitOpen 2:095b360e0f54 29 timer_.detach();
MikamiUitOpen 2:095b360e0f54 30 trigger_ = false;
MikamiUitOpen 2:095b360e0f54 31 xnM1_ = 32767;
MikamiUitOpen 2:095b360e0f54 32 filled_ = tf;
MikamiUitOpen 2:095b360e0f54 33 }
MikamiUitOpen 2:095b360e0f54 34
MikamiUitOpen 2:095b360e0f54 35 // Interrupt service routine for Ticker
MikamiUitOpen 2:095b360e0f54 36 void Sampler::Isr()
MikamiUitOpen 2:095b360e0f54 37 {
MikamiUitOpen 2:095b360e0f54 38 if (!trigger_)
MikamiUitOpen 2:095b360e0f54 39 {
MikamiUitOpen 2:095b360e0f54 40 int16_t xn = (this->*Rd[sw_])();
MikamiUitOpen 2:095b360e0f54 41 // Detect rising edge
MikamiUitOpen 2:095b360e0f54 42 if ((xn > (xnM1_+512)) && (xn > 2048))
MikamiUitOpen 2:095b360e0f54 43 trigger_ = true;
MikamiUitOpen 2:095b360e0f54 44 else
MikamiUitOpen 2:095b360e0f54 45 xnM1_ = xn;
MikamiUitOpen 2:095b360e0f54 46 return;
MikamiUitOpen 2:095b360e0f54 47 }
MikamiUitOpen 2:095b360e0f54 48
MikamiUitOpen 2:095b360e0f54 49 buffer_[count_] = (this->*Rd[sw_])(); // Read from A0
MikamiUitOpen 2:095b360e0f54 50
MikamiUitOpen 2:095b360e0f54 51 if (++count_ >= N_DATA_)
MikamiUitOpen 2:095b360e0f54 52 Set(true); // Permits spectrum analysis
MikamiUitOpen 2:095b360e0f54 53 }
MikamiUitOpen 2:095b360e0f54 54 }
MikamiUitOpen 2:095b360e0f54 55