mikroC

mikroC - C Compiler for Microchip PIC microcontrollers

making it simple...

Util Library

Util library contains miscellaneous routines useful for project development.

Button

Prototype

char Button(char *port, char pin, char time, char active_state);

 

 

Returns

Returns 0 or 255.

 

 

Description

Function eliminates the influence of contact flickering upon pressing a button (debounc-

 

ing).

 

Parameters port and pin specify location of the button; parameter time specifies the

 

minimum time pin has to be in active state in order to return TRUE; parameter

 

active_state can be either 0 or 1, and it determines if button is active upon logical

 

zero or logical one.

 

 

Example

Example reads RB0, to which the button is connected; on transition from 1 to 0 (release

 

of button), PORTD is inverted:

 

do {

 

if (Button(&PORTB, 0, 1, 1)) oldstate = 1;

 

if (oldstate && Button(&PORTB, 0, 1, 0)) {

 

PORTD = ~PORTD;

 

oldstate = 0;

 

}

 

} while(1);

 

 

page

 

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