C8051F340 Proje Geliştirme Kartı

// Source code under CC0 1.0

#include <stdbool.h>

__sfr __at(0xa0) P2;

__sfr __at(0xa6) P2MDOUT;

__sfr __at(0xe2) XBR1;

__sfr __at(0xd9) PCA0MD;

__sfr __at(0x88) TCON;

__sfr __at(0x89) TMOD;

__sfr __at(0x8a) TL0;

__sfr __at(0x8c) TH0;

__sfr __at(0xa8) IE;

volatile unsigned long int clocktime;

volatile _Bool clockupdate;

void clockinc(void) __interrupt(1)

{

        TH0 = (65536 - 125) / 256;

        TL0 = (65536 - 125) % 256;

        clocktime++;

        clockupdate = true;

}

unsigned long int clock(void)

{

        unsigned long int ctmp;

        do

        {

               clockupdate = false;

               ctmp = clocktime;

        } while (clockupdate);

        return(ctmp);

}

unsigned char _sdcc_external_startup(void)

{

    PCA0MD = 0; // Disable watchdog timer

    return 0;  // perform normal initialization

}

void main(void)

{

        // Enable port output

        XBR1 = 0x40;

        P2MDOUT = 0x0c;

        // Configure timer for 1.5 Mhz default SYSCLK

        // 1000 ticks per second

        TH0 = (65536 - 125) / 256;

        TL0 = (65536 - 125) % 256;

        TMOD = 0x01;

        IE |= 0x82;

        TCON |= 0x10; // Start timer

        for(;;)

               P2 = ((clock() / 1000) & 0x03) << 2;

}