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#include <rtl.h>
#include <rtl_fifo.h>
#include <time.h>
#include <rtl_sched.h>
#include <rtl_sync.h>
#include <pthread.h>
#include <posix/unistd.h>
pthread_t T;
void *my_code(void *);
int fd;
int stop = 0;
static void copy_device_data(unsigned int *);
#define DELAY_NS 500000 // 500 microseconds
int init_module(void){
if ( (fd = open("/dev/rtf0",O_WRONLY | O_NONBLOCK )) < 0)
{
rtl_printf("Example cannot open fifo\n");
rtl_printf("Error number is %d\n",errno);
return -1;
}
if( pthread_create(&T,NULL,my_code,NULL))
{
close(fd);
rtl_printf("Cannot create thread\n");
return -1;
}
return 0;
}
void cleanup_module(void){
stop = 1;
pthread_join(T,NULL);
close(fd);
}
void *my_code(void *arg){
struct timespec t;
struct {int i; unsigned int d; }D = {0,0};
clock_gettime(CLOCK_REALTIME,&t);
while(!stop){
copy_device_data(&D.d);
D.i++;
/* ignore write fails, we just drop the data */
write(fd,&D,sizeof(D));
timespec_add_ns(&t,DELAY_NS);
clock_nanosleep(CLOCK_REALTIME, TIMER_ABSTIME, &t, NULL);
}
return (void *)stop;
}
static void copy_device_data(unsigned int *x)
{
static int last=0;
int d;
rdtscl(d);
*x= (d - last);
last = d;
}
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