Mikroelektronika MIKROE-350 Datenbogen

This is a simple example of using the Keypad Library. It supports keypads with 1..4
rows and 1..4 columns. The code being returned by Keypad_Key_Click() function is
in range from 1..16. In this example, the code returned is transformed into ASCII
codes [0..9,A..F] and displayed on Lcd. In addition, a small single-byte counter dis-
plays in the second Lcd row number of key presses.

program Keypad_Test
dim kp, cnt, oldstate as byte

txt 

as byte[7]

' Keypad module connections
dim keypadPort as byte at PORTB
dim keypadPort_Direction as byte at DDRB
' End Keypad module connections

' Lcd pinout definition
dim LCD_RS as sbit at PORTD.2

LCD_EN 

as sbit at PORTD.3

LCD_D4 

as sbit at PORTD.4

LCD_D5 

as sbit at PORTD.5

LCD_D6 

as sbit at PORTD.6

LCD_D7 

as sbit at PORTD.7

dim LCD_RS_Direction as sbit at DDRD.2

LCD_EN_Direction 

as sbit at DDRD.3

LCD_D4_Direction 

as sbit at DDRD.4

LCD_D5_Direction 

as sbit at DDRD.5

LCD_D6_Direction 

as sbit at DDRD.6

LCD_D7_Direction 

as sbit at DDRD.7

' end Lcd pinout definitions

main:

oldstate = 0

cnt = 0                                ' Reset counter

Keypad_Init()                           ' Initialize Keypad
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

kp = 0                             ' Reset key code variable

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CHAPTER 6