soccer player substitution board

I am new to arduino can anyone help me. I want to build a soccer player substitution board that has a keypad when i press the key the 7 segment display must show the number


I need help with the software. It contain 2 red led digit and 2 green led digit. I have plane to use two arduino, one for red part and one for green part and it use two separate keypad respectively. I use 4X3 matrix keypad.

key pad looks like this

1 2 3

4 5 6

7 8 9

  • 0 #

I want a software that can print 1 digit and 2 digit numbers in the display and i want the # button use as a clear. It mean when i press the # button the display will be clear nothing will show in the display.

I am using Max 72XX to drive leds. 1 Max72xx for each digit. Do i have to connect Dout of one Max72xx to next Max72xx dIn to achive this?

thanx for the help

I am going to use MAX7219


Can you help me with how to combine the keypad part and display part in software meaner.

thanx for the kind help.

riufaan, You have three things here: 1) Keypad Search this site for post concerning keypads, the information is there I'm sure. I found the library for a similar keypad sometime ago via a search.

2) Arduino I would recommend using the ShiftOut tutorial: . With this method you can drive in excess of 16 LED Clusters by just using three arduino pins.

3) Led Clusters You have a bunch of options here but what I would recommend is using either a 7 or 13 segment cluster per digit. For example each segment can be composed of 4 LEDs that are switched on with a transistor or mosfet by the 595.

So in the end you will press 32 on the keypad and the 595 will turn on the clusters you want to form a 3 and 2 on your display. There might be a couple of holes in my logic above but this should give you some direction. Good luck and keep us informed of your progress!

I have finished the display part and its working fine when i use the example codes from the page.

//We always have to include the library
#include “LedControl.h”

Now we need a LedControl to work with.
***** These pin numbers will probably not work with your hardware *****
pin 12 is connected to the DataIn
pin 11 is connected to the CLK
pin 10 is connected to LOAD
We have only a single MAX72XX.
LedControl lc=LedControl(12,11,10,1);

/* we always wait a bit between updates of the display */
unsigned long delaytime=250;

void setup() {
The MAX72XX is in power-saving mode on startup,
we have to do a wakeup call
Set the brightness to a medium values /
and clear the display */

This method will display the characters for the
word “Arduino” one after the other on digit 0.
void writeArduinoOn7Segment() {

This method will scroll all the hexa-decimal
numbers and letters on the display. You will need at least
four 7-Segment digits. otherwise it won’t really look that good.
void scrollDigits() {
for(int i=0;i<13;i++) {

void loop() {

and keypad also working i use the code

#include <Keypad.h>

const byte ROWS = 4; //four rows
const byte COLS = 3; //four columns
char keys[ROWS][COLS] = {
byte rowPins[ROWS] = {5, 4, 3, 2}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {8, 7, 6}; //connect to the column pinouts of the keypad

Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

void setup(){

void loop(){
char key = keypad.getKey();

if (key != NO_KEY){

for the keypad.

i am not that good for coding. i want to combine this two such a way that when i press the key from key pad it will show in display. I am using 2digit 7 segment display