KEYPAD Library

Driver for using keypad in AVR - ARM Cortex M

Version : 0.0.0

• Type : Embedded Software.

• Support : AVR/ARM STM32 series.

• Program Language : C

• Properties :

Initialization and de-initialization functions:

Operation functions:

uint8_t Keypad_GetKey(void); /* Function for get pushed key */
void Keypad_Read(CommandFunction_T your_function); /* Function for read keypad and run user command */

Macros:

#define _KEYPAD_PORT 
#define _KEYPAD_PIN  
#define _KEYPAD_FIRST_ROW  
#define _KEYPAD_SCAN_SPEED  

How to use this library

The Keypad library can be used as follows:

1. Add .h and source file in project.

2. Config 4 GPIO as output for rows and 4 GPIO as input for column in your project.

• In AVR:

  DDRB = 0xF0; // 1111 0000

3. Config Keypad in 'KEYPAD_CONFIG.h' header, for example:

• Options in AVR:

  /* Set your connected port */
  
  #define _KEYPAD_PORT          &PORTB
  #define _KEYPAD_PIN           &PINB
  #define _KEYPAD_FIRST_ROW     0
  #define _KEYPAD_SCAN_SPEED    1
  

• Options in STM32:

  /* Set your connected port */
  
  #define _KEYPAD_PORT          GPIOB
  #define _KEYPAD_PIN           GPIOB
  #define _KEYPAD_FIRST_ROW     14
  #define _KEYPAD_SCAN_SPEED    1
  

4. Create your function and use operation methods, for example:

Example 1:

void MyFunction(int8_t x)
{
    /* ---- x is the pushed key ---- */
    if(x == 6)
    {
      LED_ON();
    }
    else
    { 
      LED_OFF();
    }
  
}
 
int main(void)
{
	
    while (1) 
    {
  
      Keypad_Read(MyFunction);
    
    }
}
   

Example 2:

void MyFunction(int8_t x)
{
    /* ---- x is the pushed key ---- */
    sprintf(str, "%u", x); /* cast pushed key number to string */
    Lcd_PutString(str); /* show pushed key in the LCD */
}
 
int main(void)
{
	
    while (1) 
    {
  
      Keypad_Read(MyFunction);
    
    }
}
   

Example 3:

uint8_t key_character[16] = {'1' , '2' , '3' , 'A' , '4' , '5' , '6', 'B' , '7' , '8' , '9' , 'C' , '*' , '0' , '#' , 'D'};

void ShowKey(int8_t x)
{
    /* ---- x is the pushed key ---- */
    Lcd_PutChar(key_character[ch]); /* Show character */
}
 
int main(void)
{
	
    while (1) 
    {
  
      Keypad_Read(ShowKey);
    
    }
}
   

Tests performed:

• Run on AVR
• Run on STM32 Fx cores

Developer: Majid Derhambakhsh