How to make a quick Arduino to Cadaces adapter.

Some people asked me for a simpler way to interface the Cadaces modules to an Arduino, so here it is!

All you need to do this is a five pin header and four jumper wires.  Insert the five pin header into D1 through D5.  Then plug the cable from the display into those five pins so the other five pins hang off to the right.  Add the four jumper wires according to the schematic.

 Here is a picture of the quick adapter in operation.  The green wire if 5 volts going to power the sign.

Here are the pin number changes to the code to make it work;

// Pins for the row drivers

int row1Pin = 2;            //R1

int row2Pin = 7;            //R2

int row3Pin = 1;            //R3

int rowEnable = 8;        //REN

int rclockPin = 6;          //RCK

int clockPin = 3;           //SCK

int dataPin = 5;             //RSD

int gdataPin = 4;           //GSD

Here is the total code for 8 x 40 array:

//**********************************

//  Name    : Cadaces Driver                         

//  Author  : Bob Davis                                  

//  Date    : 23 February, 2013                                 

//  Version : 1.0                                             

//**********************************

// Pins for the row drivers

int row1Pin = 2;         //R1

int row2Pin = 7;         //R2

int row3Pin = 1;         //R3

int rowEnable = 8;     //REN

int rclockPin = 6;        //RCK

int clockPin = 3;         //SCK

int dataPin = 5;          //RSD

int gdataPin = 4;        //GSD

// Set the pins to output to the sign

void setup() {

  pinMode(row1Pin, OUTPUT);

  pinMode(row2Pin, OUTPUT);

  pinMode(row3Pin, OUTPUT);

  pinMode(rowEnable, OUTPUT);

  pinMode(rclockPin, OUTPUT);

  pinMode(clockPin, OUTPUT);

  pinMode(dataPin, OUTPUT);

  pinMode(gdataPin, OUTPUT);

}

byte bitmap[][8] = {  //red characters

  {0, 0,0,0,0,0,0,0},

  {0,  4, 10, 17, 17, 31, 17, 17}, //A

  {0, 30, 17, 17, 30, 20, 18, 17}, //R

  {0, 28, 18, 17, 17, 17, 18, 28}, //D

  {0, 0,0,0,0,0,0,0},

  {0, 14, 04, 04, 04, 04, 04, 14}, //I

  {0, 17, 25, 25, 21, 19, 19, 17}, //N

  {0, 14, 17, 17, 17, 17, 17, 14}, //O

  {0, 0,0,0,0,0,0,0},

};

byte gbitmap[][8] = {  //green characters

  {0, 0,0,0,0,0,0,0},

  {0,  4, 10, 17, 17, 31, 17, 17}, //A

  {0, 30, 17, 17, 30, 20, 18, 17}, //R

  {0, 0,0,0,0,0,0,0},

  {0, 17, 17, 17, 17, 17, 17, 14}, //U

  {0, 14, 04, 04, 04, 04, 04, 14}, //I

  {0, 0,0,0,0,0,0,0},

  {0, 14, 17, 17, 17, 17, 17, 14}, //O

  {0, 0,0,0,0,0,0,0},

};

void RunSign(){

  for (int row = 7; row > 0; row--) {

    // turn off display

    digitalWrite(rowEnable, HIGH);

    digitalWrite(rclockPin, LOW);

    // send serial data to display 8 = number of characters

    for (int character = 0; character < 8; character++){

     for (int shiftbit = 5; shiftbit > -1; shiftbit--){

      digitalWrite(gdataPin, LOW);

      digitalWrite(dataPin, LOW);

      if bitRead(gbitmap[character][row],shiftbit) digitalWrite(gdataPin, HIGH);

      if bitRead(bitmap[character][row],shiftbit) digitalWrite(dataPin, HIGH);

      digitalWrite(clockPin, HIGH); digitalWrite(clockPin, LOW);

    } }

    //latch the data

    digitalWrite(rclockPin, HIGH);

    // set up 74138 row selection and turn display back on

    digitalWrite(row1Pin, LOW);

    digitalWrite(row2Pin, LOW);

    digitalWrite(row3Pin, LOW);

    if bitRead(row,0) digitalWrite (row1Pin, HIGH);

    if bitRead(row,1) digitalWrite (row2Pin, HIGH);

    if bitRead(row,2) digitalWrite (row3Pin, HIGH);

    digitalWrite(rowEnable, LOW);

    // Wait to see what we sent to the display ;

    delayMicroseconds(500);

  }

} 

//=== L O O P ===

void loop() {

  RunSign();

}