不韋 呂 / Mbed 2 deprecated UIT2_FIR_LPF_Symmetry

FIR filter of symmetric coefficiemts for ST Nucleo F401RE.

Dependencies:   UIT_ADDA mbed

main.cpp@6:eaab05429e1d, 2014-11-15 (annotated)

Committer:
MikamiUitOpen
Date:
Sat Nov 15 06:11:08 2014 +0000
Revision:
6:eaab05429e1d
Parent:
5:b81eb5e88546 
7

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:4912234b4155 1 //--------------------------------------------------------------
MikamiUitOpen 0:4912234b4155 2 // FIR フィルタ，係数の対称性を利用する構造
MikamiUitOpen 0:4912234b4155 3 // Analog Input : A0
MikamiUitOpen 0:4912234b4155 4 // Analog Output: MCP4922 using SPI
MikamiUitOpen 5:b81eb5e88546 5 // 2014/11/12, Copyright (c) 2014 MIKAMI, Naoki
MikamiUitOpen 0:4912234b4155 6 //--------------------------------------------------------------
MikamiUitOpen 0:4912234b4155 7
MikamiUitOpen 0:4912234b4155 8 #include "mbed.h"
MikamiUitOpen 0:4912234b4155 9
MikamiUitOpen 1:93d2771b8797 10 #include "ADC_Base.hpp" // for ADC not using interrupt
MikamiUitOpen 0:4912234b4155 11 #include "DAC_MCP4922.hpp" // for DAC MCP4922
MikamiUitOpen 0:4912234b4155 12 #include "Coefficients_200_LPF_Sym.hpp"
MikamiUitOpen 0:4912234b4155 13
MikamiUitOpen 0:4912234b4155 14 using namespace Mikami;
MikamiUitOpen 0:4912234b4155 15
MikamiUitOpen 3:89bae16a8d2c 16 const int FS_ = 12000; // Sampling frequency: 12 kHz
MikamiUitOpen 3:89bae16a8d2c 17 ADC_Base adc_(A0, FS_); // for AD
MikamiUitOpen 3:89bae16a8d2c 18 DAC_MCP4922 myDac_; // for DA
MikamiUitOpen 0:4912234b4155 19
MikamiUitOpen 0:4912234b4155 20 int main()
MikamiUitOpen 0:4912234b4155 21 {
MikamiUitOpen 5:b81eb5e88546 22 myDac_.ScfClockTim3(500000); // cutoff frequency: 5 kHz
MikamiUitOpen 0:4912234b4155 23
MikamiUitOpen 0:4912234b4155 24 float xn[ORDER_+1];
MikamiUitOpen 0:4912234b4155 25 for (int n=0; n<=ORDER_; n++)
MikamiUitOpen 0:4912234b4155 26 xn[n] = 0;
MikamiUitOpen 0:4912234b4155 27
MikamiUitOpen 0:4912234b4155 28 while (true)
MikamiUitOpen 0:4912234b4155 29 {
MikamiUitOpen 0:4912234b4155 30 xn[0] = adc_.Read(); // Read from A0
MikamiUitOpen 0:4912234b4155 31 //-----------------------------------------------
MikamiUitOpen 0:4912234b4155 32
MikamiUitOpen 0:4912234b4155 33 float yn = hm_[ORDER_/2]*xn[ORDER_/2];
MikamiUitOpen 0:4912234b4155 34 for (int k=0; k<ORDER_/2; k++)
MikamiUitOpen 0:4912234b4155 35 yn = yn + hm_[k]*(xn[k] + xn[ORDER_-k]);
MikamiUitOpen 0:4912234b4155 36
MikamiUitOpen 0:4912234b4155 37 for (int k=ORDER_; k>0; k--)
MikamiUitOpen 0:4912234b4155 38 xn[k] = xn[k-1]; // move input signals
MikamiUitOpen 0:4912234b4155 39
MikamiUitOpen 0:4912234b4155 40 //-----------------------------------------------
MikamiUitOpen 0:4912234b4155 41 myDac_.Write(yn); // Write to DAC
MikamiUitOpen 0:4912234b4155 42 }
MikamiUitOpen 0:4912234b4155 43 }