Page 122 - ARM Based Microcontroller Projects Using MBED

108 7. USING THE Mbed WITH SIMPLE PROJECTS

BEGIN
Configure and group LEDs as outputs
Configure button as input
Cnt = 0
Turn OFF all LEDs at the beginning
DO FOREVER
IF button is pressed THEN
Increment CNT
Display CNT on LEDs in binary
ENDIF
ENDDO
END
FIG. 7.45 PDL of the program.

/*****************************************************************************
BINARY EVENT COUNTER WITH LEDS
==============================
In this program 8 LEDs are connected to lower byte of PORT C. The program
simulates an ebent counter such that when the User button is pressed a
count is incremented by one and is then displayed on the LEDs.

Author: Dogan Ibrahim
Date : August 2018
File : Events
***************************************************************************/
#include "mbed.h"
BusOut LEDS(PC_0,PC_1,PC_2,PC_3,PC_4,PC_5,PC_6,PC_7);
DigitalIn button(BUTTON1);

int main()
{
int Cnt = 0; // Cnt = 0 to start with
LEDS = 0; // All LEDs OFF at beginning

while(1) // DO Forever
{
if(button == 0) // If button is pressed
{
Cnt++; // Increment Cnt
LEDS = Cnt; // Display Cnt
while(button == 0); // Wait until button released
}
}
}

FIG. 7.46 Program listing.