Rob Toulson / Mbed 2 deprecated PE_11-02_LPFFunction

by Rob Toulson and Tim Wilmshurst from textbook "Fast and Effective Embedded Systems Design: Applying the ARM mbed"

Dependencies:   mbed

Embed: (wiki syntax)

« Back to documentation index

Show/hide line numbers main.cpp Source File

main.cpp

00001 /*Program Example 11.2 Low pass filter function 
00002                                               */
00003 float LPF(float LPF_in){
00004     
00005   float a[4]={1,2.6235518066,-2.3146825811,0.6855359773};
00006   float b[4]={0.0006993496,0.0020980489,0.0020980489,0.0006993496};
00007   static float LPF_out;
00008   static float x[4], y[4];  
00009 
00010   x[3] = x[2]; x[2] = x[1]; x[1] = x[0];  //move x values by one sample
00011   y[3] = y[2]; y[2] = y[1]; y[1] = y[0];  //move y values by one sample
00012  
00013   x[0] = LPF_in;                          // new value for x[0] 
00014   y[0] =   (b[0]*x[0]) + (b[1]*x[1]) + (b[2]*x[2]) + (b[3]*x[3])                       
00015             + (a[1]*y[1]) + (a[2]*y[2]) + (a[3]*y[3]);
00016 
00017   LPF_out = y[0]; 
00018   return LPF_out;                         // output filtered value
00019 }
00020
Generated on Tue Aug 2 2022 01:27:52 by  doxygen 1.7.2