Keypad - Multiple Value Read [resolved]

Projects Networking, Protocols, and Devices
1

Good Morning, I'm trying to using keypad and then read a multiple value ... in the specific cases I'd like to press '*' blink 2 times the led and then read the second one value for example one ... and then put everything inside a variable and print it on serial ... due the fact Im not able to say to the keypad for the second charachter after blink 2 times ... wait at max un second if the user I press key read the keypad read a key otherwise go on ... below the code ... is there someone that can help me ? thanks Andrea

#include <Keypad.h>

const byte ROWS = 4; //four rows
const byte COLS = 3; //three columns
char keys[ROWS][COLS] = {
  {'1','2','3'},
  {'4','5','6'},
  {'7','8','9'},
  {'*','0','#'}
};
byte rowPins[ROWS] = {8, 7, 6, 5}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {4, 3, 2}; //connect to the column pinouts of the keypad

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

void setup(){
  Serial.begin(9600);
  pinMode(13, OUTPUT);
  digitalWrite(13,LOW);
}
  
void loop(){
  char customKey = customKeypad.getKey();
  char customKey2;
  char testo[1];
  if (customKey != NO_KEY)
    {
    if (customKey = '*') 
      {
       int a = 1;
       int cont = 3;
       asled(a,cont);
       customKey2 = customKeypad.getKey();
       a = 1;
       cont = 4;
       asled(a,cont);
       testo[0] = customKey;
       testo[1] = customKey2;
      }  
    Serial.println(testo);
    
    }
}

void asled(int a,int cont)
{
  for (a = 1; a < cont; a++)
    {
     digitalWrite(13, HIGH);
     delay(150);
     digitalWrite(13, LOW);
     delay(150);
    }
  
}
2

to read multiple keys can imply that you need a keybuffer.
Add a timer (millis based) that checks the duration between keypresses and if too long wipe the buffer.

char testo[1]; is an array of length 1 so only index 0 is valid and you use index 1 too , will overwrite something in memory.

some code idea how to do the wiping and buffering

char buffer[10];
int index = 0;
unsigned long lastKey = 0;

void loop()
{
  // read a key
  char key = customKeypad.getKey();
  if (key != NO_KEY)
  {
    buffer[index++] = key;
    buffer[index] = '\0'; // keep string correctly terminated ;
    lastKey = millis();
  }

  // test wipe time
  if ((millis() - 2000 > lastKey) || index == 9) // after 2 seconds or buffer full
  {
    clearBuffer();
  }


  if (buffer[0] == '*' && strlen(buffer)>1)
  {
    switch(buffer[1])
    {
    case '0' : 
      asled(10); 
      break;
    case '1' : 
      asled(20); 
      break;
    default : 
      asled(5); 
      break;
    }
  }

  if (buffer[0] == '#' && strlen(buffer)>1)
  {
    switch(buffer[1])
    {
    case '0' : Serial.println("Hello ");
      break;
    case '1' : Serial.println("Goodbye ");
      break;
    default : 
      asled(5); 
      break;
    }
  }

  Serial.println(buffer);
}

void clearBuffer()
{
    index = 0; 
    buffer[index] = '\0'; 
}

void asled(int cont)
{
  for (int a = 0; a < cont; a++)
    {
     digitalWrite(13, HIGH);
     delay(150);
     digitalWrite(13, LOW);
     delay(150);
    }
}
3

Ciao, it's a very good idea :slight_smile: I will try and then I'll let you know :slight_smile: ,

Perfect, it's work

I've added also end command :slight_smile: thanks

warms regards,
Andrea