Intel 8XC196NT, Руководство пользователя

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8XC196NT USER’S MANUAL
10-34
void poll_epa0()
{
if(checkbit(int_pend, EPA0_INT_BIT))
{
/* User code for event channel 0 would go here. */
/* Since this event is absolute and re-enabled, no polling is neccessary.*/
clrbit(int_pend, EPA0_INT_BIT);
}
}
void main(void)
{
/* Initialize the timers before using the epa */
init_timer1();
init_epa0();
/* EPA events can be serviced by polling int_pend
or epa_pend. */
while(1)
{
poll_epa0();
}
}
10.9.2 EPA Capture Event Program
This example C program demonstrates an EPA capture event. It sets up EPA channel 0 to capture
edges (rising and falling) on the EPA0 pin. The program also shows how to set up the EPA inter-
rupts. You can add your own code for the interrupt service routine.
#pragma model()
#include <80c196kr.h>
#define COUNT_ENABLE 0x80
#define COUNT_UP 0x40
#define CLOCK_INTERNAL 0x00
#define DIVIDE_BY_1 0x00
#define CAPTURE 0x00
#define BOTH_EDGE 0x30
#define USE_TIMER1 0x00
#define EPA0_INT_BIT 4
void init_epa0()
{
epa0_con = CAPTURE |
BOTH_EDGE |
USE_TIMER1;
setbit(p1_reg, 0); /* int reg */
setbit(p1_dir, 0); /* make input pin */
setbit(p1_mode, 0); /* select EPA mode */
setbit(int_mask, EPA0_INT_BIT); /* unmask EPA interrupts */
}
#pragma interrupt(epa0_interrupt=EPA0_INT_BIT)
void epa0_interrupt()
{
unsigned int time_value;