m-Bé
A guitar Tuner project made by: Guarino Yuri Pota Giuseppe Sito Leonardo It is made up of a circuit for signal amplification(using LM386 OP-AMP), and a circuit of many LEDs that display if the guitar is tuned or not. For digital signal processing we used mbed-dsp library.
Diff: main.cpp
- Revision:
- 0:2529b7b37e9a
- Child:
- 1:45d485b8966f
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Sun Dec 09 15:58:55 2018 +0000
@@ -0,0 +1,356 @@
+#include "mbed.h"
+ #include "mbed.h"
+#include "arm_math.h"
+#include "arm_const_structs.h"
+#define SAMP_FREQ 2000
+
+InterruptIn button(PC_13);
+DigitalOut El(D2);
+DigitalOut A(D3);
+DigitalOut D(D4);
+DigitalOut G(D5);
+DigitalOut B(D6);
+DigitalOut Eh(D7);
+DigitalOut Led_Ok(D9);
+DigitalOut Led_Down(D10);
+DigitalOut Led_Up(D8);
+Serial pc (SERIAL_TX,SERIAL_RX);
+AnalogIn analog_value(A0);
+const int FFT_LEN = 1024;
+const int bins = 1000;
+
+float Ing[FFT_LEN];
+
+const static arm_cfft_instance_f32 *S;
+
+float samples[FFT_LEN*2];
+float magnitudes[FFT_LEN];
+float freq_window[bins];
+
+int c =0;
+ void selectNote() {
+ c++;
+ if(c==1)
+ {
+ El=1;
+ A=0;
+ D=0;
+ G=0;
+ B=0;
+ Eh=0;
+ }
+ else if(c==2)
+ {
+ El=0;
+ A=1;
+ D=0;
+ G=0;
+ B=0;
+ Eh=0;
+
+ }
+ else if(c==3)
+ {
+ El=0;
+ A=0;
+ D=1;
+ G=0;
+ B=0;
+ Eh=0;
+
+ }
+
+ else if(c==4)
+ {
+ El=0;
+ A=0;
+ D=0;
+ G=1;
+ B=0;
+ Eh=0;
+
+ }
+
+ else if(c==5)
+ {
+ El=0;
+ A=0;
+ D=0;
+ G=0;
+ B=1;
+ Eh=0;
+
+ }
+
+ else if(c==6)
+ {
+ El=0;
+ A=0;
+ D=0;
+ G=0;
+ B=0;
+ Eh=1;
+
+
+ }
+ else if(c==7)
+ c=0;
+
+ }
+int main() {
+ El=0;
+ A=0;
+ D=0;
+ G=0;
+ B=0;
+ Eh=0;
+
+ El=1;wait(0.1);El=0;
+ A=1;wait(0.1);A=0;
+ D=1;wait(0.1);D=0;
+ G=1;wait(0.1);G=0;
+ B=1;wait(0.1);B=0;
+ Eh=1;wait(0.1);Eh=0;
+ El=1;A=1;D=1;G=1;B=1;Eh=1;wait(0.2);
+ El=0;A=0;D=0;G=0;B=0;Eh=0;
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+
+
+
+ int32_t i = 0;
+ pc.printf("\r\n\r\nFFT test program!\r\n");
+
+
+ // Init arm_ccft_32
+ switch (FFT_LEN)
+ {
+ case 16:
+ S = & arm_cfft_sR_f32_len16;
+ break;
+ case 32:
+ S = & arm_cfft_sR_f32_len32;
+ break;
+ case 64:
+ S = & arm_cfft_sR_f32_len64;
+ break;
+ case 128:
+ S = & arm_cfft_sR_f32_len128;
+ break;
+ case 256:
+ S = & arm_cfft_sR_f32_len256;
+ break;
+ case 512:
+ S = & arm_cfft_sR_f32_len512;
+ break;
+ case 1024:
+ S = & arm_cfft_sR_f32_len1024;
+ break;
+ case 2048:
+ S = & arm_cfft_sR_f32_len2048;
+ break;
+ case 4096:
+ S = & arm_cfft_sR_f32_len4096;
+ break;
+ }
+ while(1) {
+ button.rise(&selectNote);
+ for (int k = 0; k < 1024; k++) {
+ Ing[k] = (short) (analog_value.read_u16() - 0x8000); // read unsigned 16-bit and convert to signed 16-bit (subtract 32768)
+ wait_us(1e6/SAMP_FREQ);
+ }
+ //Riempiamo il vettore per la FFT
+ for(i = 0; i< FFT_LEN*2; i+=2)
+ {
+
+ samples[i] = Ing[i];
+ samples[i+1] = 0;
+ }
+ arm_cfft_f32(S, samples, 0, 1);
+ // Calculate magnitude of complex numbers output by the FFT.
+ arm_cmplx_mag_f32(samples, magnitudes, FFT_LEN);
+
+ if(c==1){
+ int max=3;
+ int j=2;
+ do{
+ if (magnitudes[j]>magnitudes[max]&&(j*1000/1024<100)&&(j*1000/1024>30))//restringo la banda a [30Hz, 100Hz]
+ max=j;
+ j++;
+
+ }while(j<1024/2);
+
+ float maxx=(float)max*1000/1024;
+ //pc.printf("Il massimo in ampiezza è alla frequenza %f Hertz \n",(float)max*1000/1024);
+ if(maxx<82){
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+ }
+ if(maxx>84){
+ Led_Down=0;
+ Led_Up=1;
+ Led_Ok=0;
+ }
+ else if(maxx>82.3 &&maxx<=84){
+ Led_Down=0;
+ Led_Up=0;
+ Led_Ok=1;
+ }
+ }
+ //--------------A STRING------------------
+ if(c==2){
+ int max=3;
+ int j=2;
+ do{
+
+ if (magnitudes[j]>magnitudes[max]&&(j*1000/1024<130)&&(j*1000/1024>90))//restringo la banda a [90Hz, 130Hz]
+ max=j;
+ j++;
+
+ }while(j<1024/2);
+
+ float maxx=(float)max*1000/1024;
+ //pc.printf("Il massimo in ampiezza è alla frequenza %f Hertz \n",(float)max*1000/1024);
+ if(maxx<110){
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+ }
+ if(maxx>112){
+ Led_Down=0;
+ Led_Up=1;
+ Led_Ok=0;
+ }
+ else if(maxx>110 &&maxx<113){
+ Led_Down=0;
+ Led_Up=0;
+ Led_Ok=1;
+ }
+ }
+ //--------------D STRING------------------
+ if(c==3){
+ int max=3;
+ int j=2;
+ do{
+
+ if (magnitudes[j]>magnitudes[max]&&(j*1000/1024<160)&&(j*1000/1024>130))//restringo la banda a [90Hz, 130Hz]
+ max=j;
+ j++;
+
+ }while(j<1024/2);
+
+ float maxx=(float)max*1000/1024;
+ //pc.printf("Il massimo in ampiezza è alla frequenza %f Hertz \n",(float)max*1000/1024);
+ if(maxx<147){
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+ }
+ if(maxx>149){
+ Led_Down=0;
+ Led_Up=1;
+ Led_Ok=0;
+ }
+ else if(maxx>147 &&maxx<149){
+ Led_Down=0;
+ Led_Up=0;
+ Led_Ok=1;
+ }
+ }
+ //--------------G STRING------------------
+ if(c==4){
+ int max=3;
+ int j=2;
+ do{
+
+ if (magnitudes[j]>magnitudes[max]&&(j*1000/1024<210)&&(j*1000/1024>170))//restringo la banda a [90Hz, 130Hz]
+ max=j;
+ j++;
+
+ }while(j<1024/2);
+
+ float maxx=(float)max*1000/1024;
+ //pc.printf("Il massimo in ampiezza è alla frequenza %f Hertz \n",(float)max*1000/1024);
+ if(maxx<196){
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+ }
+ if(maxx>203){
+ Led_Down=0;
+ Led_Up=1;
+ Led_Ok=0;
+ }
+ else if(maxx>=196 &&maxx<=197.5){
+ Led_Down=0;
+ Led_Up=0;
+ Led_Ok=1;
+ }
+ }
+ //--------------B STRING------------------
+ if(c==5){
+ int max=3;
+ int j=2;
+ do{
+
+ if (magnitudes[j]>magnitudes[max]&&(j*1000/1024<260)&&(j*1000/1024>230))//restringo la banda a [90Hz, 130Hz]
+ max=j;
+ j++;
+
+ }while(j<1024/2);
+
+ float maxx=(float)max*1000/1024;
+ //pc.printf("Il massimo in ampiezza è alla frequenza %f Hertz \n",(float)max*1000/1024);
+ if(maxx<244){
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+ }
+ if(maxx>250){
+ Led_Down=0;
+ Led_Up=1;
+ Led_Ok=0;
+ }
+ else if(maxx>246 &&maxx<250){
+ Led_Down=0;
+ Led_Up=0;
+ Led_Ok=1;
+ }
+ }
+ //--------------Eh STRING------------------
+ if(c==6){
+ int max=3;
+ int j=2;
+ do{
+
+ if (magnitudes[j]>magnitudes[max]&&(j*1000/1024<340)&&(j*1000/1024>310))//restringo la banda a [90Hz, 130Hz]
+ max=j;
+ j++;
+
+ }while(j<1024/2);
+
+ float maxx=(float)max*1000/1024;
+ //pc.printf("Il massimo in ampiezza è alla frequenza %f Hertz \n",(float)max*1000/1024);
+ if(maxx<327){
+ Led_Down=1;
+ Led_Up=0;
+ Led_Ok=0;
+ }
+ if(maxx>334){
+ Led_Down=0;
+ Led_Up=1;
+ Led_Ok=0;
+ }
+ else if(maxx>330.3 &&maxx<333.5){
+ Led_Down=0;
+ Led_Up=0;
+ Led_Ok=1;
+ }
+ }
+
+
+ }
+}
+