By Karltjuh92
#6681
Hey all,

I am new these embedded systems. I really like it. I only got one problem, some days ago I recieved my Matrix keybad FIT0129 ([url=http://www.dfrobot.com/index.php?route=product/product&filter_name=FIT0129&product_id=450]http://www.dfrobot.com/index.php?route=product/product&filter_name=FIT0129&product_id=450[/url])

I dont know how to use it really so I made this: ( written in c with the arduino IDE)

char cycle(){
  delay(50);
digitalWrite(8,HIGH);
  if(digitalRead(7)==HIGH){
    return '0';
  } else if (digitalRead(6)==HIGH){
      return '#';
  }else if (digitalRead(5)==HIGH){
      return '*';
  }else if (digitalRead(4)==HIGH){
      return 'D';
  }
  digitalWrite(8,LOW);
 
  delay(50);
  digitalWrite(9,HIGH);
 
  if(digitalRead(7)==HIGH){
            return '8';
  } else if (digitalRead(6)==HIGH){
          return '9';
  }else if (digitalRead(5)==HIGH){
        return '7';
  }else if (digitalRead(4)==HIGH){
        return 'C';
  }
  digitalWrite(9,LOW);
 
  delay(50);
  digitalWrite(10,HIGH);
 
  if(digitalRead(7)==HIGH){
        return '5';
  } else if (digitalRead(6)==HIGH){
          return '6';
  }else if (digitalRead(5)==HIGH){
          return '4';
  }else if (digitalRead(4)==HIGH){
          return 'B';
  }
  digitalWrite(10,LOW);
 
  delay(50);
    digitalWrite(11,HIGH);

  if(digitalRead(7)==HIGH){       
    return '2';
  } else if (digitalRead(6)==HIGH){
          return '3';
}else if (digitalRead(5)==HIGH){
          return '1';
  }else if (digitalRead(4)==HIGH){
          return 'A';
  }
  digitalWrite(11,LOW);
}

In this part of the code i want to return the input char. (that works well i guess)

in this part I want to change a case with it but it doesnt work well
        if(cycle()=='1'){
        inputCase = 1;
     

Does someone know what is the problem?

Greets
Karl
By Hector
#6682
Hi Karl,


I found this sample code on the net. You might need to change the pins either in the program or physically to match each other.


[code]
/*  Keypadtest.pde
*
*  Demonstrate the simplest use of the  keypad library.
*
*  The first step is to connect your keypad to the
*  Arduino  using the pin numbers listed below in
*  rowPins[] and colPins[]. If you want to use different
*  pins then  you  can  change  the  numbers below to
*  match your setup.
*
*/
#include <Keypad.h>

const byte ROWS = 4; // Four rows
const byte COLS = 3; // Three columns
// Define the Keymap
char keys[ROWS][COLS] = {
  {'1','2','3'},
  {'4','5','6'},
  {'7','8','9'},
  {'#','0','*'}
};
// Connect keypad ROW0, ROW1, ROW2 and ROW3 to these Arduino pins.
byte rowPins[ROWS] = { 9, 8, 7, 6 };
// Connect keypad COL0, COL1 and COL2 to these Arduino pins.
byte colPins[COLS] = { 12, 11, 10 };

// Create the Keypad
Keypad kpd = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

#define ledpin 13

void setup()
{
  digitalWrite(ledpin, HIGH);
  Serial.begin(9600);
}

void loop()
{
  char key = kpd.getKey();
  if(key)  // Check for a valid key.
  {
    switch (key)
    {
      case '*':
        digitalWrite(ledpin, LOW);
        break;
      case '#':
        digitalWrite(ledpin, HIGH);
        break;
      default:
        Serial.println(key);
    }
  }
}
[/code]
By Hector
#6683
I also found this post which teaches you how to use only 3 wires. I think its pretty cool and worth a try


[url=http://www.instructables.com/id/Arduino-3-wire-Matrix-Keypad/]http://www.instructables.com/id/Arduino-3-wire-Matrix-Keypad/[/url]

By Karltjuh92
#6685
Oh Thanks for the unlock, I can reply finally. Thank you for your help! I'm still new at the forum it worked good! Thanks!