Bonjour,
Je suis en train de réaliser une télécommande DTMF avec l'Arduino.
J'ai trouvé pour cela une Librairie qui fonctionne à merveille. Décodage sans problème et affichage sur l’ordinateur via serie.
Maintenant j'aimerai que, lors de la réception du code DTMF: 1234, ma Led s'allume.
J'ai essayé plusieurs méthode et fait quelques recherche, mais je n'y arrive pas.
EDIT: J'ai peut être été vite en besogne. Je n'arrive déjà pas à allumer ma Led avec 1 DTMF reçu.
Comment récupérer le chiffre "5" décodé par la librairie. le but étant d'allumer la led a la reception du code DTMF 5 correspondant au clavier de ma radio.
J'ai essayé:
if (thischar){
digitalWrite(led, HIGH);
}
La led s'allume, mais avec tous les caractères. (déjà bien, elle s'allume donc pas de soucis matériel)
et avec:
if (thischar == 5){
digitalWrite(led, HIGH);
}
ça ne fonctionne pas.
Voici la sources de la librairie: http://members.shaw.ca/el.supremo/DTMF.zip
et le code:
// The library toggles digital pin 4 in the sampling loop which allows
// measurement of the actual sampling frequency.
// If you call .sample() continuously like this:
// while(1)dtmf.sample(sensorPin);
// you can put a frequency counter on pin 4 to determine what the
// sampling frequency is on your Arduino. Note that the frequency
// counter will show half the actual rate. My meter showed 4.463kHz
// so the sampling rate is 8926Hz
#include <DTMF.h>
int sensorPin = A0;
int led = 13;
// NOTE that N MUST NOT exceed 160
// This is the number of samples which are taken in a call to
// .sample. The smaller the value of N the wider the bandwidth.
// For example, with N=128 at a sample rate of 8926Hz the tone
// detection bandwidth will be 8926/128 = 70Hz. If you make N
// smaller, the bandwidth increases which makes it harder to detect
// the tones because some of the energy of one tone can cross into
// an adjacent (in frequency) tone. But a larger value of N also means
// that it takes longer to collect the samples.
// A value of 64 works just fine, as does 128.
// NOTE that the value of N does NOT have to be a power of 2.
float n=128.0;
// sampling rate in Hz
float sampling_rate=8926.0;
// Instantiate the dtmf library with the number of samples to be taken
// and the sampling rate.
DTMF dtmf = DTMF(n,sampling_rate);
void setup(){
pinMode(led, OUTPUT);
Serial.begin(115200);
}
int nochar_count = 0;
float d_mags[8];
void loop()
{
char thischar;
// This reads N samples from sensorpin (must be an analog input)
// and stores them in an array within the library. Use while(1)
// to determine the actual sampling frequency as described in the
// comment at the top of this file
/* while(1) */dtmf.sample(sensorPin);
// The first argument is the address of a user-supplied array
// of 8 floats in which the function will return the magnitudes
// of the eight tones.
// The second argument is the value read by the ADC when there
// is no signal present. A voltage divider with precisely equal
// resistors will presumably give a value of 511 or 512.
// My divider gives a value of 506.
// If you aren't sure what to use, set this to 512
dtmf.detect(d_mags,506);
// detect the button
// If it is recognized, returns one of 0123456789ABCD*#
// If unrecognized, returns binary zero
// Pass it the magnitude array used when calling .sample
// and specify a magnitude which is used as the threshold
// for determining whether a tone is present or not
//
// If N=64 magnitude needs to be around 1200
// If N=128 the magnitude can be set to 1800
// but you will need to play with it to get the right value
thischar = dtmf.button(d_mags,1800.);
if(thischar) {
Serial.print(thischar);
nochar_count = 0;
// Print the magnitudes for debugging
//#define DEBUG_PRINT
#ifdef DEBUG_PRINT
for(int i = 0;i < 8;i++) {
Serial.print(" ");
Serial.print(d_mags[i]);
}
Serial.println("");
#endif
} else {
// print a newline
if(++nochar_count == 50)Serial.println("");
// don't let it wrap around
if(nochar_count > 30000)nochar_count = 51;
}
}
Merci
