main.cpp

00001 //--------------------------------------------------------------
00002 /**
00003  * FFT experiment for LPC1114FN28
00004  *
00005  * programed by Takehisa Oneta(ohneta)
00006  * Aug. 2015
00007  */
00008 //--------------------------------------------------------------
00009 
00010 #include "fftReal.hpp"
00011 #include "mbed.h"
00012 
00013 #define     SAMPLING_NUM    64
00014 //#define     SAMPLING_NUM    32
00015 //--------------------------------------------------------------
00016 
00017 Serial pc(USBTX, USBRX);
00018 AnalogIn  ainR(dp9);
00019 AnalogIn  ainL(dp10);
00020 Ticker soundInterrupt;
00021 
00022 const char *gBarGraf[] = {
00023     "                               ",
00024     "*                              ",
00025     "**                             ",
00026     "***                            ",
00027     "****                           ",
00028     "*****                          ",
00029     "******                         ",
00030     "*******                        ",
00031     "********                       ",
00032     "*********                      ",
00033     "**********                     ",
00034     "***********                    ",
00035     "************                   ",
00036     "*************                  ",
00037     "**************                 ",
00038     "***************                ",
00039     "****************               ",
00040     "*****************              ",
00041     "******************             ",
00042     "*******************            ",
00043     "********************           ",
00044     "*********************          ",
00045     "**********************         ",
00046     "***********************        ",
00047     "************************       ",
00048     "*************************      ",
00049     "**************************     ",
00050     "***************************    ",
00051     "****************************   ",
00052     "*****************************  ",
00053     "****************************** ",
00054     "*******************************",
00055 };
00056 
00057 //--------------------------------------------------------------
00058 
00059 
00060 uint32_t  gSoundIntrFlag = 0;
00061 uint32_t  gSoundIntrCount = 0;
00062 
00063 float  gBufferR[SAMPLING_NUM];
00064 float  gBufferL[SAMPLING_NUM];
00065 
00066 //----------------------------------------------------
00067 /**
00068  * Ticker handler
00069  */
00070 void soundInterruptHandle()
00071 {
00072     if (gSoundIntrFlag == 0) {
00073         gSoundIntrFlag = 1;
00074     }
00075 }
00076 
00077 //----------------------------------------------------
00078 
00079 int main()
00080 {
00081     pc.baud(115200);
00082  
00083     Complex y1[SAMPLING_NUM / 2 + 1];
00084     Complex y2[SAMPLING_NUM / 2 + 1];
00085 
00086     pc.printf("### START \n");
00087 
00088     gSoundIntrFlag = 0;
00089     gSoundIntrCount = 0;
00090     uint32_t intr_us = 25;  //
00091     soundInterrupt.attach_us(&soundInterruptHandle, intr_us);
00092 
00093 float dd = 20.0f;
00094 
00095     FftReal fft(SAMPLING_NUM);
00096     while (1) {
00097         
00098         if (gSoundIntrFlag == 1) {
00099             float r = ainR;
00100             float l = ainL;
00101             
00102             //pc.printf("*** [%02d] = %8.4f : %8.4f \n", gSoundIntrCount, r,  l);
00103 
00104             gBufferR[gSoundIntrCount] = r * dd - 1.0f;
00105             if (gBufferR[gSoundIntrCount] < -1.0f) {
00106                 gBufferR[gSoundIntrCount] = -1.0f;
00107             } else if (gBufferR[gSoundIntrCount] > 1.0f) {
00108                 gBufferR[gSoundIntrCount] = 1.0f;
00109             }
00110             gBufferL[gSoundIntrCount] = l * dd - 1.0f;
00111             if (gBufferL[gSoundIntrCount] < -1.0f) {
00112                 gBufferL[gSoundIntrCount] = -1.0f;
00113             } else if (gBufferL[gSoundIntrCount] > 1.0f) {
00114                 gBufferL[gSoundIntrCount] = 1.0f;
00115             }
00116             //pc.printf("*** [%02d] = %2.4f : %2.4f : %2.4f : %2.4f \n", gSoundIntrCount, r, l, gBufferR[gSoundIntrCount], gBufferL[gSoundIntrCount]);
00117             //pc.printf("\n");
00118  
00119             gSoundIntrCount++;
00120             if (gSoundIntrCount >= SAMPLING_NUM) {
00121                 gSoundIntrCount = 0;
00122 
00123                 fft.Execute(gBufferR, y1);
00124                 fft.Execute(gBufferL, y2);
00125 
00126                 //pc.printf("%c[2J%c[;H", 27, 27);
00127                 pc.printf("%c[%c;%cH", 27, 0, 0);
00128                 //pc.printf("%c[;H", 27);
00129 
00130 
00131                 pc.printf("    [Right]                           [Left]\r\n");
00132                 for (int n = 0; n <= (SAMPLING_NUM / 2); n++) {
00133                     uint32_t dtR = (uint32_t)abs(y1[n]);
00134                     if (dtR >= (SAMPLING_NUM / 2)) {
00135                         dtR = 15;
00136                     }
00137                     
00138                     uint32_t dtL = (uint32_t)abs(y2[n]);
00139                     if (dtL >= (SAMPLING_NUM / 2)) {
00140                         dtL = 15;
00141                     }
00142 
00143                     pc.printf("%2d: %s : %s\r\n", n, gBarGraf[dtR], gBarGraf[dtL]);
00144                 }
00145 
00146            }
00147            gSoundIntrFlag = 0;
00148         }
00149    }
00150 
00151 }
00152 
00153 //----------------------------------------------------