RT-Thread-为啥释放不出来信号量？帮忙看看程序RT-Thread问答社区

为啥释放不出来信号量？帮忙看看程序

发布于 2013-03-05 11:57:12 浏览：3596 订阅该版

```extern void rt_hw_key_init(void);
static struct rt_semaphore static_sem;
ALIGN(RT_ALIGN_SIZE)
static rt_uint8_t led_stack[ 1024 ];
static struct rt_thread led_thread;
static void led_thread_entry(void* parameter)
{
    unsigned int count=0;
    rt_err_t result;
    rt_tick_t tick;
    rt_hw_led_init();
    while (1)
    {
        // rt_sem_release(&static_sem); //:shock: ①处
        result = rt_sem_take(&static_sem, RT_WAITING_FOREVER);
        if (result != RT_EOK)
        {
            rt_kprintf("take a static semaphore, failed.
");
            rt_sem_detach(&static_sem);
            return;
        }

rt_kprintf("take a staic semaphore, done.
");

rt_sem_detach(&static_sem);
        /* led1 on */
#ifndef RT_USING_FINSH
        rt_kprintf("led on, count : %d
",count);
#endif
        count++;
        rt_hw_led_on(0);
        rt_thread_delay( RT_TICK_PER_SECOND/2 ); /* sleep 0.5 second and switch to other thread */

/* led1 off */
#ifndef RT_USING_FINSH
        rt_kprintf("led off
");
#endif
        rt_hw_led_off(0);
        rt_thread_delay( RT_TICK_PER_SECOND/2 );
    }
}

static void key_thread_entry(void *parameter)
{
    rt_time_t next_delay;
    struct rtgui_event_kbd kbd_event;

/* init keyboard event */
    RTGUI_EVENT_KBD_INIT(&kbd_event);
    kbd_event.mod  = RTGUI_KMOD_NONE;
    kbd_event.unicode = 0;

while (1)
    {
        next_delay = 50;
        kbd_event.key = RTGUIK_UNKNOWN;
        kbd_event.type = RTGUI_KEYDOWN;

if ( key_down_GETVALUE()  == 0 )
        {
            rt_kprintf("key_down
");
            kbd_event.key  = RTGUIK_DOWN;
            rt_sem_release(&static_sem); // :shock: ②处
        }

if ( key_up_GETVALUE()    == 0 )
        {
            rt_kprintf("key_up
");
            kbd_event.key  = RTGUIK_UP;
        }

if ( key_right_GETVALUE() == 0 )
        {
            rt_kprintf("key_right
");
            kbd_event.key  = RTGUIK_RIGHT;
        }

if ( key_left_GETVALUE()  == 0 )
        {
            rt_kprintf("key_left
");
            kbd_event.key  = RTGUIK_LEFT;
        }

if (kbd_event.key != RTGUIK_UNKNOWN)
        {
            /* post down event */
            //     rtgui_server_post_event(&(kbd_event.parent), sizeof(kbd_event));

//  next_delay = 10;
            //   /* delay to post up event */
            //   rt_thread_delay(next_delay);

/* post up event */
            //   kbd_event.type = RTGUI_KEYUP;
            //   rtgui_server_post_event(&(kbd_event.parent), sizeof(kbd_event));
        }

GPIOB->ODR ^= GPIO_Pin_5;
        /* wait next key press */
        rt_thread_delay(next_delay);
    }
}

static char key_stack[1024];
static rt_thread_t key_tid;
struct rt_thread key;
void rt_hw_key_init(void)
{
    rt_err_t result;
    GPIO_Configuration();
    /*    key_tid = rt_thread_init("key",
                           &key_thread_entry, RT_NULL,
                           1024, 11, 30);
    */
    rt_thread_init(&key,
                   "key", //consumer
                   key_thread_entry,
                   RT_NULL,
                   (rt_uint8_t*)&key_stack[0],
                   sizeof(key_stack),11,24);
    if (result == RT_EOK)
    {
        rt_thread_startup(&key);
    }
}

int rt_application_init()
{
    rt_thread_t init_thread;
    rt_err_t result;

result = rt_sem_init(&static_sem, "ssem", 0, RT_IPC_FLAG_FIFO);
    if (result != RT_EOK)
    {
        rt_kprintf("init dynamic semaphore failed.
");
        return -1;
    }

rt_hw_key_init();
    /* init led thread */
    result = rt_thread_init(&led_thread,
                            "led",
                            led_thread_entry, RT_NULL,
                            (rt_uint8_t*)&led_stack[0], sizeof(led_stack), 11, 30);

if (result == RT_EOK)
    {
        rt_thread_startup(&led_thread);
    }

init_thread = rt_thread_create("init",
                                   rt_init_thread_entry, RT_NULL, 2048, 8, 20);

if (init_thread != RT_NULL)
        rt_thread_startup(init_thread);

return 0;
}
```
我本意是通过按键释放信号量，指示灯收到后动作。结果奇怪了！按键线程已经工作，并且按key_down键能够串口输出key_down 
但运行过②处的rt_sem_release(&static_sem);  后static_sem的value并没有+1；所以LED不动作。但是在LED线程中①处的rt_sem_release(&static_sem); 使能后，LED线程能够正常运行，不能满足我的要求。KEY的现场动态  静态添加都试过  均失败！ 点解？