FIR filter of Direct form for ST Nucleo F401RE.

Dependencies:   UITDSP_ADDA mbed

Committer:
MikamiUitOpen
Date:
Tue Oct 21 08:37:42 2014 +0000
Revision:
0:bbbc6e10e439
Child:
1:124262641129
1

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:bbbc6e10e439 1 //--------------------------------------------------------------
MikamiUitOpen 0:bbbc6e10e439 2 // FIR フィルタ,基本的な構造
MikamiUitOpen 0:bbbc6e10e439 3 // Analog Input : A0
MikamiUitOpen 0:bbbc6e10e439 4 // Analog Output: MCP4922 using SPI
MikamiUitOpen 0:bbbc6e10e439 5 // 2014/10/21, Copyright (c) 2014 MIKAMI, Naoki
MikamiUitOpen 0:bbbc6e10e439 6 //--------------------------------------------------------------
MikamiUitOpen 0:bbbc6e10e439 7
MikamiUitOpen 0:bbbc6e10e439 8 #include "mbed.h"
MikamiUitOpen 0:bbbc6e10e439 9
MikamiUitOpen 0:bbbc6e10e439 10 #include "ADC_Interrupt.hpp" // for ADC using interrupt
MikamiUitOpen 0:bbbc6e10e439 11 #include "DAC_MCP4922.hpp" // for DAC MCP4922
MikamiUitOpen 0:bbbc6e10e439 12 #include "ScfClockTim3.hpp" // for clock supplied to SCF
MikamiUitOpen 0:bbbc6e10e439 13 #include "Coefficients_200_LPF.hpp"
MikamiUitOpen 0:bbbc6e10e439 14
MikamiUitOpen 0:bbbc6e10e439 15 using namespace Mikami;
MikamiUitOpen 0:bbbc6e10e439 16
MikamiUitOpen 0:bbbc6e10e439 17 const int FS_ = 12000; // Sampling frequency: 12 kHz
MikamiUitOpen 0:bbbc6e10e439 18 ADC_Base adc_(A0, FS_); // for AD
MikamiUitOpen 0:bbbc6e10e439 19 DAC_MCP4922 myDac_(DAC_MCP4922::DAC_A); // for DA
MikamiUitOpen 0:bbbc6e10e439 20
MikamiUitOpen 0:bbbc6e10e439 21 int main()
MikamiUitOpen 0:bbbc6e10e439 22 {
MikamiUitOpen 0:bbbc6e10e439 23 ScfClockTim3(500000); // cutoff frequency: 5 kHz
MikamiUitOpen 0:bbbc6e10e439 24
MikamiUitOpen 0:bbbc6e10e439 25 float xn[ORDER_+1];
MikamiUitOpen 0:bbbc6e10e439 26 for (int n=0; n<=ORDER_; n++)
MikamiUitOpen 0:bbbc6e10e439 27 xn[n] = 0;
MikamiUitOpen 0:bbbc6e10e439 28
MikamiUitOpen 0:bbbc6e10e439 29 while (true)
MikamiUitOpen 0:bbbc6e10e439 30 {
MikamiUitOpen 0:bbbc6e10e439 31 xn[0] = adc_.Read(); // Read from A0
MikamiUitOpen 0:bbbc6e10e439 32 //-----------------------------------------------
MikamiUitOpen 0:bbbc6e10e439 33
MikamiUitOpen 0:bbbc6e10e439 34 float yn = 0;
MikamiUitOpen 0:bbbc6e10e439 35 for (int k=0; k<=ORDER_; k++)
MikamiUitOpen 0:bbbc6e10e439 36 yn = yn + hm_[k]*xn[k];
MikamiUitOpen 0:bbbc6e10e439 37
MikamiUitOpen 0:bbbc6e10e439 38 for (int k=ORDER_; k>0; k--)
MikamiUitOpen 0:bbbc6e10e439 39 xn[k] = xn[k-1]; // move input signals
MikamiUitOpen 0:bbbc6e10e439 40
MikamiUitOpen 0:bbbc6e10e439 41 //-----------------------------------------------
MikamiUitOpen 0:bbbc6e10e439 42 myDac_.Write(yn); // Write to DAC
MikamiUitOpen 0:bbbc6e10e439 43 }
MikamiUitOpen 0:bbbc6e10e439 44 }