#include <pthread.h>
#include "encryption_chip.h"
#define GPIO_NUM PAD_GPIO20
#define GPIO_DEV "/dev/gpioctl"
#define SERIAL_DEV "/dev/ttyS4"
int efd;
volatile int flag = 0;//些处要用volatile限定,以防被优化
void *thr(void *arg)
{
int i = 0;
char c;
while(1) {
if (flag == 1) { //被优化后,些处永远执行不到,一直为假
read(efd, &c, 1);
printf("receive data[%d]: 0x%x\n", i++, c);
}
}
}
int main(void)
{
//char data[] = {0x80, 0x08, 0x00, 0x00, 0x05, 0x01, 0x11, 0x22, 0x33, 0x44};
int gpio_num = GPIO_NUM;
pthread_t tid_rx;
if( 0 != pthread_create(&tid_rx, NULL, thr, NULL))
printf("can't create receive thread");
efd = encryption_chip_open(SERIAL_DEV, GPIO_DEV, gpio_num);
flag = 1;
pthread_join(tid_rx, NULL);
encryption_chip_close(efd);
return 0;
}
volatile的问题
最新推荐文章于 2024-09-05 23:07:17 发布