Datasheet

Keypad 4x4
MikroElektronika
program Keypad_Test;
var kp, cnt, oldstate : byte;
txt : array[6] of byte;
// Keypad module connections
var keypadPort : byte at PORTD;
// End Keypad module connections
// Lcd module connections
var LCD_RS : sbit at RB4_bit;
LCD_EN : sbit at RB5_bit;
LCD_D4 : sbit at RB0_bit;
LCD_D5 : sbit at RB1_bit;
LCD_D6 : sbit at RB2_bit;
LCD_D7 : sbit at RB3_bit;
var LCD_RS_Direction : sbit at TRISB4_bit;
LCD_EN_Direction : sbit at TRISB5_bit;
LCD_D4_Direction : sbit at TRISB0_bit;
LCD_D5_Direction : sbit at TRISB1_bit;
LCD_D6_Direction : sbit at TRISB2_bit;
LCD_D7_Direction : sbit at TRISB3_bit;
// End Lcd module connections
begin
oldstate := 0;
cnt := 0; // Reset counter
Keypad_Init(); // Initialize Keypad
ANSEL := 0; // Congure AN pins as digital I/O
ANSELH := 0;
Lcd_Init(); // Initialize Lcd
Lcd_Cmd(_LCD_CLEAR); // Clear display
Lcd_Cmd(_LCD_CURSOR_OFF); // Cursor off
Lcd_Out(1, 1, ‘Key :’); // Write message text on Lcd
Lcd_Out(2, 1, ‘Times:’);
while TRUE do
begin
kp := 0; // Reset key code variable
// Wait for key to be pressed and released
while ( kp = 0 ) do
kp := Keypad_Key_Click(); // Store key code in kp variable
// Prepare value for output, transform key to it’s ASCII value
case kp of
//case 10: kp = 42; // ‘*’ // Uncomment this block for keypad4x3
//case 11: kp = 48; // ‘0’
//case 12: kp = 35; // ‘#’
//default: kp += 48;
1: kp := 49; // 1 // Uncomment this block for keypad4x4
2: kp := 50; // 2
3: kp := 51; // 3
4: kp := 65; // A
5: kp := 52; // 4
6: kp := 53; // 5
7: kp := 54; // 6
8: kp := 66; // B
9: kp := 55; // 7
10: kp := 56; // 8
11: kp := 57; // 9
12: kp := 67; // C
13: kp := 42; // *
14: kp := 48; // 0
15: kp := 35; // #
16: kp := 68; // D
end;
if (kp <> oldstate) then // Pressed key differs from previous
begin
cnt := 1;
oldstate := kp;
end
else // Pressed key is same as previous
Inc(cnt);
Lcd_Chr(1, 10, kp); // Print key ASCII value on Lcd
if (cnt = 255) then // If counter varialble overow
begin
cnt := 0;
Lcd_Out(2, 10, ‘ ‘);
end;
WordToStr(cnt, txt); // Transform counter value to string
Lcd_Out(2, 10, txt); // Display counter value on Lcd
end;
end.
Example 3: Program written in mikroPascal PRO for PIC