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我想使用民意調查()函數得到基於GPIO的中斷在BeagleBone GPIO上工作。下面是我的代碼,但總之:使用民意調查BeagleBone黑色GPIO中斷()
雖然我有針連接到地面,沒有任何反應(如預期)。
當我將引腳連接到高電平時,會產生中斷。然而,它永遠不會清除或以極快的速度再生。我實施了一個計數器,當它升高時,計數器會增加,在幾秒鐘內,計數器就超過10,000。我在設置中丟失了什麼?這個問題可能在我的main()函數中,但我已經包含了其他函數的完整性。
感謝您的任何援助,
查爾斯
#define SYSFS_GPIO_DIR "/sys/class/gpio"
#define MAX_BUF 64
int gpio_export(unsigned int gpio)
{
int fd, len;
char buf[MAX_BUF];
fd = open(SYSFS_GPIO_DIR "/export", O_WRONLY);
if (fd < 0) {
perror("gpio/export");
return fd;
}
len = snprintf(buf, sizeof(buf), "%d", gpio);
write(fd, buf, len);
close(fd);
return 0;
}
int gpio_set_dir(unsigned int gpio, unsigned int direction)
{
int fd, len;
char buf[MAX_BUF];
len = snprintf(buf, sizeof(buf), SYSFS_GPIO_DIR "/gpio%d/direction", gpio);
fd = open(buf, O_WRONLY);
if (fd < 0) {
perror("gpio/direction");
return fd;
}
if (direction)
write(fd, "out", 4);
else
write(fd, "in", 3);
close(fd);
return 0;
}
int gpio_set_edge(unsigned int gpio, char *edge)
{
int fd, len;
char buf[MAX_BUF];
len = snprintf(buf, sizeof(buf), SYSFS_GPIO_DIR "/gpio%d/edge", gpio);
fd = open(buf, O_WRONLY);
if (fd < 0) {
perror("gpio/set-edge");
return fd;
}
write(fd, edge, strlen(edge) + 1);
close(fd);
return 0;
}
int gpio_fd_open(unsigned int gpio)
{
int fd, len;
char buf[MAX_BUF];
len = snprintf(buf, sizeof(buf), SYSFS_GPIO_DIR "/gpio%d/value", gpio);
fd = open(buf, O_RDONLY | O_NONBLOCK);
if (fd < 0) {
perror("gpio/fd_open");
}
return fd;
}
int gpio_fd_close(int fd)
{
return close(fd);
}
int main()
{
struct pollfd fdset;
int nfds = 1;
int gpio_fd, timeout, rc;
char *buf[MAX_BUF];
unsigned int gpio;
int len;
char* c;
gpio = 26;
gpio_export(gpio);
gpio_set_dir(gpio, 0);
gpio_set_edge(gpio, "rising");
gpio_fd = gpio_fd_open(gpio);
timeout = 1;
while (1) {
memset((void*)&fdset, 0, sizeof(fdset));
fdset.fd = gpio_fd;
fdset.events = POLLPRI | POLLERR;
len = read(fdset.fd, c, 1);
rc = poll(&fdset, nfds, timeout);
//printf("POLLPRI is %02x, POLLERR is %02x\r\n", POLLPRI, POLLERR);
if (rc < 0) {
printf("\npoll() failed!\n");
return -1;
}
if (rc == 0) {
printf(".");
}
if (fdset.revents & POLLPRI) {
if (len==-1)
{
printf("Hex of revents is %02x, return code is %02x\r\n", fdset.revents, rc);
}
len = read(fdset.fd, buf, MAX_BUF);
}
if (fdset.revents & POLLERR)
{
printf("errno: %d", errno);
}
}
gpio_fd_close(gpio_fd);
return 0;
}
我沒有讀過你的代碼,但是如果你通過機械開關或類似的(開路線)「連接」,你必須反彈(只搜索術語)。 – Olaf