jim hamblen / Mbed 2 deprecated Pushbutton_BadBounce_Interrupt

Pushbutton demo using interrupts with switch contact bounce

Dependencies:   mbed

main.cpp@1:6582c095e8d1, 2011-10-06 (annotated)

Committer:
4180_1
Date:
Thu Oct 06 00:55:26 2011 +0000
Revision:
1:6582c095e8d1
Parent:
0:7db73d1dc65f 

        

        
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#include "mbed.h"





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DigitalOut myled(LED1);





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DigitalOut myled2(LED2);





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DigitalOut myled3(LED3);





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DigitalOut myled4(LED4);





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InterruptIn pb(p8);





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// SPST Pushbutton count demo using interrupts





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// no external PullUp resistor needed





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// Pushbutton from P8 to GND.





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// A pb hit generates an interrupt and activates the interrupt routine





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// Global count variable





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int volatile count=0;





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// pb Interrupt routine - is interrupt activated by a falling edge of pb input





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void pb_hit_interrupt (void) {





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    count++;





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    myled4 = count & 0x01;





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    myled3 = (count & 0x02)>>1;





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    myled2 = (count & 0x04)>>2;





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}





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int main() {





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    // Use internal pullup for pushbutton





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    pb.mode(PullUp);





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    // Delay for initial pullup to take effect





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    wait(.01);





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    // Attach the address of the interrupt handler routine for pushbutton





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    pb.fall(&pb_hit_interrupt);





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    // Blink myled in main routine forever while responding to pb changes





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    // via interrupts that activate pb_hit_interrupt routine





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    while (1) {





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        myled = !myled;





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        wait(.5);





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    }





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}