Merci infobarquee de ton intention 
J'ai trouvé ce programme où l'on modifie le nombre de MAX utilisé à ce point là -> int maxInUse = 2
mais qu'on le modifie ça ne change rien 
/*
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Texte défilant
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*/
#include <MaxMatrix.h>
#define PROG_TYPE_COMPAT
#include <avr/pgmspace.h>
PROGMEM const unsigned char CH[] = {
3, 8, B00000000, B00000000, B00000000, B00000000, B00000000, // space
1, 8, B01011111, B00000000, B00000000, B00000000, B00000000, // !
3, 8, B00000011, B00000000, B00000011, B00000000, B00000000, // "
5, 8, B00010100, B00111110, B00010100, B00111110, B00010100, // #
4, 8, B00100100, B01101010, B00101011, B00010010, B00000000, // $
5, 8, B01100011, B00010011, B00001000, B01100100, B01100011, // %
5, 8, B00110110, B01001001, B01010110, B00100000, B01010000, // &
1, 8, B00000011, B00000000, B00000000, B00000000, B00000000, // '
3, 8, B00011100, B00100010, B01000001, B00000000, B00000000, // (
3, 8, B01000001, B00100010, B00011100, B00000000, B00000000, // )
5, 8, B00101000, B00011000, B00001110, B00011000, B00101000, // *
5, 8, B00001000, B00001000, B00111110, B00001000, B00001000, // +
2, 8, B10110000, B01110000, B00000000, B00000000, B00000000, // ,
4, 8, B00001000, B00001000, B00001000, B00001000, B00000000, // -
2, 8, B01100000, B01100000, B00000000, B00000000, B00000000, // .
4, 8, B01100000, B00011000, B00000110, B00000001, B00000000, // /
4, 8, B00111110, B01000001, B01000001, B00111110, B00000000, // 0
3, 8, B01000010, B01111111, B01000000, B00000000, B00000000, // 1
4, 8, B01100010, B01010001, B01001001, B01000110, B00000000, // 2
4, 8, B00100010, B01000001, B01001001, B00110110, B00000000, // 3
4, 8, B00011000, B00010100, B00010010, B01111111, B00000000, // 4
4, 8, B00100111, B01000101, B01000101, B00111001, B00000000, // 5
4, 8, B00111110, B01001001, B01001001, B00110000, B00000000, // 6
4, 8, B01100001, B00010001, B00001001, B00000111, B00000000, // 7
4, 8, B00110110, B01001001, B01001001, B00110110, B00000000, // 8
4, 8, B00000110, B01001001, B01001001, B00111110, B00000000, // 9
2, 8, B01010000, B00000000, B00000000, B00000000, B00000000, // :
2, 8, B10000000, B01010000, B00000000, B00000000, B00000000, // ;
3, 8, B00010000, B00101000, B01000100, B00000000, B00000000, // <
3, 8, B00010100, B00010100, B00010100, B00000000, B00000000, // =
3, 8, B01000100, B00101000, B00010000, B00000000, B00000000, // >
4, 8, B00000010, B01011001, B00001001, B00000110, B00000000, // ?
5, 8, B00111110, B01001001, B01010101, B01011101, B00001110, // @
4, 8, B01111110, B00010001, B00010001, B01111110, B00000000, // A
4, 8, B01111111, B01001001, B01001001, B00110110, B00000000, // B
4, 8, B00111110, B01000001, B01000001, B00100010, B00000000, // C
4, 8, B01111111, B01000001, B01000001, B00111110, B00000000, // D
4, 8, B01111111, B01001001, B01001001, B01000001, B00000000, // E
4, 8, B01111111, B00001001, B00001001, B00000001, B00000000, // F
4, 8, B00111110, B01000001, B01001001, B01111010, B00000000, // G
4, 8, B01111111, B00001000, B00001000, B01111111, B00000000, // H
3, 8, B01000001, B01111111, B01000001, B00000000, B00000000, // I
4, 8, B00110000, B01000000, B01000001, B00111111, B00000000, // J
4, 8, B01111111, B00001000, B00010100, B01100011, B00000000, // K
4, 8, B01111111, B01000000, B01000000, B01000000, B00000000, // L
5, 8, B01111111, B00000010, B00001100, B00000010, B01111111, // M
5, 8, B01111111, B00000100, B00001000, B00010000, B01111111, // N
4, 8, B00111110, B01000001, B01000001, B00111110, B00000000, // O
4, 8, B01111111, B00001001, B00001001, B00000110, B00000000, // P
4, 8, B00111110, B01000001, B01000001, B10111110, B00000000, // Q
4, 8, B01111111, B00001001, B00001001, B01110110, B00000000, // R
4, 8, B01000110, B01001001, B01001001, B00110010, B00000000, // S
5, 8, B00000001, B00000001, B01111111, B00000001, B00000001, // T
4, 8, B00111111, B01000000, B01000000, B00111111, B00000000, // U
5, 8, B00001111, B00110000, B01000000, B00110000, B00001111, // V
5, 8, B00111111, B01000000, B00111000, B01000000, B00111111, // W
5, 8, B01100011, B00010100, B00001000, B00010100, B01100011, // X
5, 8, B00000111, B00001000, B01110000, B00001000, B00000111, // Y
4, 8, B01100001, B01010001, B01001001, B01000111, B00000000, // Z
2, 8, B01111111, B01000001, B00000000, B00000000, B00000000, // [
4, 8, B00000001, B00000110, B00011000, B01100000, B00000000, // \ backslash
2, 8, B01000001, B01111111, B00000000, B00000000, B00000000, // ]
3, 8, B00000010, B00000001, B00000010, B00000000, B00000000, // AT
4, 8, B01000000, B01000000, B01000000, B01000000, B00000000, // _
2, 8, B00000001, B00000010, B00000000, B00000000, B00000000, // `
4, 8, B00100000, B01010100, B01010100, B01111000, B00000000, // a
4, 8, B01111111, B01000100, B01000100, B00111000, B00000000, // b
4, 8, B00111000, B01000100, B01000100, B00101000, B00000000, // c
4, 8, B00111000, B01000100, B01000100, B01111111, B00000000, // d
4, 8, B00111000, B01010100, B01010100, B00011000, B00000000, // e
3, 8, B00000100, B01111110, B00000101, B00000000, B00000000, // f
4, 8, B10011000, B10100100, B10100100, B01111000, B00000000, // g
4, 8, B01111111, B00000100, B00000100, B01111000, B00000000, // h
3, 8, B01000100, B01111101, B01000000, B00000000, B00000000, // i
4, 8, B01000000, B10000000, B10000100, B01111101, B00000000, // j
4, 8, B01111111, B00010000, B00101000, B01000100, B00000000, // k
3, 8, B01000001, B01111111, B01000000, B00000000, B00000000, // l
5, 8, B01111100, B00000100, B01111100, B00000100, B01111000, // m
4, 8, B01111100, B00000100, B00000100, B01111000, B00000000, // n
4, 8, B00111000, B01000100, B01000100, B00111000, B00000000, // o
4, 8, B11111100, B00100100, B00100100, B00011000, B00000000, // p
4, 8, B00011000, B00100100, B00100100, B11111100, B00000000, // q
4, 8, B01111100, B00001000, B00000100, B00000100, B00000000, // r
4, 8, B01001000, B01010100, B01010100, B00100100, B00000000, // s
3, 8, B00000100, B00111111, B01000100, B00000000, B00000000, // t
4, 8, B00111100, B01000000, B01000000, B01111100, B00000000, // u
5, 8, B00011100, B00100000, B01000000, B00100000, B00011100, // v
5, 8, B00111100, B01000000, B00111100, B01000000, B00111100, // w
5, 8, B01000100, B00101000, B00010000, B00101000, B01000100, // x
4, 8, B10011100, B10100000, B10100000, B01111100, B00000000, // y
3, 8, B01100100, B01010100, B01001100, B00000000, B00000000, // z
3, 8, B00001000, B00110110, B01000001, B00000000, B00000000, // {
1, 8, B01111111, B00000000, B00000000, B00000000, B00000000, // |
3, 8, B01000001, B00110110, B00001000, B00000000, B00000000, // }
4, 8, B00001000, B00000100, B00001000, B00000100, B00000000, // ~
};
int data = 12;
int load = 10;
int clock = 11;
int maxInUse = 2; //A modifier pour changer le nombre d'afficheur, ici on en a deux
MaxMatrix m(data, load, clock, maxInUse);
byte buffer[10];
// Les lignes de texte vous pouvez en rajoutez mais attention a la limite de la mémoire
char string1[] = " Jojo Bricolo ... ";
char string2[] = " Vous souhaite la bienvenue ";
char string3[] = " sur arduino-creations-blogspot.fr ";
void setup(){
m.init(); // initialisation du MAX7219
m.setIntensity(10); // Règlage de l'intensité lumineuse de 0 a 15
Serial.begin(9600); // initialisation du prot série
}
void loop(){
printStringWithShift(string1, 100); // 100 = vitesse de défilement soit 100ms
printStringWithShift(string2, 100);
printStringWithShift(string3, 100);
}
void printCharWithShift(char c, int shift_speed){
if (c < 32) return;
c -= 32;
memcpy_P(buffer, CH + 7*c, 7);
m.writeSprite(32, 0, buffer);
m.setColumn(32 + buffer[0], 0);
for (int i=0; i<buffer[0]+1; i++)
{
delay(shift_speed);
m.shiftLeft(false, false);
}
}
void printStringWithShift(char* s, int shift_speed){
while (*s != 0){
printCharWithShift(*s, shift_speed);
s++;
}
}
void printString(char* s)
{
int col = 0;
while (*s != 0)
{
if (*s < 32) continue;
char c = s - 32;
memcpy_P(buffer, CH + 7c, 7);
m.writeSprite(col, 0, buffer);
m.setColumn(col + buffer[0], 0);
col += buffer[0] + 1;
s++;
}
}