Senseur ultrasonique sr04 avec panneau leds 16x32

Bonjour

jessaie sans succès d’intégrer un panneau led 16x32 de Freetronics (DMD display panel) sur un duemilanove.

Actuellement mon code marche a leception que je nai pas de donnees affichees sur le panneau.

je connais tres mal les fonctions strings et les informations du panneau led (librairies DMD) drawtext, finalstring et createtext…

voici mon code : il marche tres bien pour sortir en port serie sur un terminal windows.
jai po et cm daffiches sur le panneau sur 2 lignes differentes, mais aucunes donnees saffiche sur le panneau.
connaisser vous quelque tutos en francais ?

merci

#include <SPI.h>
#include <DMD.h>
#include <TimerOne.h>
#include “SystemFont5x7.h”
#include “Arial_black_16.h”

const int triggerPin = 2;
const int echoPin = 3;

#define DISPLAYS_ACROSS 2 // 16x64 pixels
#define DISPLAYS_DOWN 1
DMD dmd(DISPLAYS_ACROSS, DISPLAYS_DOWN);

void ScanDMD()
{
dmd.scanDisplayBySPI();
}

long microsecondsToInches(long microseconds)
{
// *** THIS NEEDS TO BE CHECKED FOR THE HC-SR04 ***
return microseconds / 74 / 2;
}

long microsecondsToCentimeters(long microseconds)
{
// *** THIS NEEDS TO BE CHECKED FOR THE HC-SR04 ***
return microseconds / 29 / 2;
}

void setup()
{
// communications pour le terminal windows.
Serial.begin(9600);

Timer1.initialize( 5000 );
Timer1.attachInterrupt( ScanDMD );
dmd.clearScreen( true );
}

void loop()
{
// establish variables for duration of the ping,
// and the distance result in inches and centimeters:
long duration, inches, cm;

// The device is triggered by a HIGH pulse of 2 or more microseconds.
// Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
pinMode(triggerPin, OUTPUT);
digitalWrite(triggerPin, LOW);
delayMicroseconds(2);
digitalWrite(triggerPin, HIGH);
delayMicroseconds(5);
digitalWrite(triggerPin, LOW);

// The echo pin is used to read the signal from the device: a HIGH
// pulse whose duration is the time (in microseconds) from the sending
// of the ping to the reception of its echo off of an object.
pinMode(echoPin, INPUT);
duration = pulseIn(echoPin, HIGH);

// convert the time into a distance
inches = microsecondsToInches(duration);
cm = microsecondsToCentimeters(duration);

Serial.print(inches);
Serial.print(" po, “);
Serial.print(cm);
Serial.print(” cm");
Serial.println();

delay(1000);

dmd.clearScreen( true );

dmd.selectFont(System5x7);
dmd.drawString( 1,0, “po”, 2, GRAPHICS_NORMAL );
dmd.drawString( 1,8, “cm”, 2, GRAPHICS_NORMAL );

delay(1000);
}