不韋 呂
/
UIT2_FIR_LPF_Symmetry
FIR filter of symmetric coefficiemts for ST Nucleo F401RE.
main.cpp@5:b81eb5e88546, 2014-11-12 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Wed Nov 12 09:55:15 2014 +0000
- Revision:
- 5:b81eb5e88546
- Parent:
- 3:89bae16a8d2c
6
Who changed what in which revision?
User | Revision | Line number | New 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 | } |