z-stack中的voidHalLedBlink (uint8 leds, uint8 numBlinks, uint8 percent, uint16 period)函數的深度解析 :
參數:
Leds: 哪個led;
numBlinks: 閃爍次數
percent: 閃爍的佔空比(就是高電平持續的時間)
period: 一個閃爍的週期多少
///////////////////////////////////////////////////////////////////////////////
HalLedBlink函數原型------
第一段代碼:
void HalLedBlink (uint8 leds, uint8numBlinks, uint8 percent, uint16 period)
{
#if (defined (BLINK_LEDS)) &&(HAL_LED == TRUE)
uint8 led;
HalLedControl_t *sts;
if(leds && percent && period)
{
if (percent < 100)
{
led = HAL_LED_1;
leds &= HAL_LED_ALL;
sts = HalLedStatusControl.HalLedControlTable;
while (leds) //循環通過led <<= 1 找出需要閃爍的燈;sts++相對應的狀態
{
if (leds & led) //找出我們設置閃爍的燈後滿足條件進入設置對應的參數,這裏涉及兩個結構體
//HalLedControl_t和HalLedStatus_t,裏面分別定義了相應的屬性(請看其定義這裏不列出);
// HalLedControlTable這個是HalLedControl_t結構體變量,用來存放控制燈模式的表,
//這個在HalLedStatus_t結構體裏面定義,其實就相當一個結構體數組,
{
/* Store the current state of the led before going to blinking if notalready blinking */
if(sts->mode < HAL_LED_MODE_BLINK )
preBlinkState |= (led &HalLedState);
sts->mode =HAL_LED_MODE_OFF; /*Stop previous blink */
sts->time = period; /* Time for oneon/off cycle */
sts->onPct = percent; /* % of cycle LED ison */
sts->todo = numBlinks; /* Number of blinkcycles */
if (!numBlinks) sts->mode |= HAL_LED_MODE_FLASH; /* Continuous */
sts->next = osal_GetSystemClock(); /* Start now */
sts->mode |= HAL_LED_MODE_BLINK; /* Enable blinking */
leds ^= led;
}
led <<= 1;
sts++;
}
// Cancel any overlapping timer for blink events
osal_stop_timerEx(Hal_TaskID, HAL_LED_BLINK_EVENT);
osal_set_event (Hal_TaskID, HAL_LED_BLINK_EVENT); //設置led閃爍事件,通過這個事件對燈進行控制,跳到第二段程序執行
}
else
{
HalLedSet (leds, HAL_LED_MODE_ON); /* >= 100%, turn on */
}
}
else
{
HalLedSet (leds, HAL_LED_MODE_OFF); /* No on time, turn off */
}
#elif (HAL_LED == TRUE)
percent = (leds & HalLedState) ? HAL_LED_MODE_OFF : HAL_LED_MODE_ON;
HalLedOnOff (leds, percent); /* Toggle */
#else
//HAL LED is disabled, suppress unused argument warnings
(void) leds;
(void) numBlinks;
(void) percent;
(void) period;
#endif /* BLINK_LEDS && HAL_LED */
}
////////////////////////////////////////////////////////
第二段代碼:
if ( events & HAL_LED_BLINK_EVENT )
{
#if (defined (BLINK_LEDS)) &&(HAL_LED == TRUE)
HalLedUpdate(); //如果定義了BLINK_LEDS和HAL_LED == TRUE就執行此句,下面繼續看第三段代碼
#endif /* BLINK_LEDS && HAL_LED */
return events ^ HAL_LED_BLINK_EVENT;
}
/////////////////////////////////////////////////////////
第三段代碼:
void HalLedUpdate (void)
{
……
……
while (leds)
{
if (leds & led)
{
if (sts->mode & HAL_LED_MODE_BLINK)
{
time = osal_GetSystemClock();
if (time >= sts->next)
{
if (sts->mode & HAL_LED_MODE_ON)
{
pct = 100 - sts->onPct; /* Percentage of cycle for off */
sts->mode &=~HAL_LED_MODE_ON; /* Say it's not on */
HalLedOnOff (led,HAL_LED_MODE_OFF); /* Turn it off */ //重點來了,這個就是操作led電平函數,繼續看第四段代碼
//由於這個函數太多沒有完全列出來,也沒分析完我們就看重點
if (!(sts->mode &HAL_LED_MODE_FLASH))
{
sts->todo--; /* Not continuous,reduce count */
}
}
else if ( (!sts->todo) && !(sts->mode &HAL_LED_MODE_FLASH) )
{
sts->mode ^=HAL_LED_MODE_BLINK; /* No moreblinks */
}
else
{
pct = sts->onPct; /* Percentage of cycle foron */
sts->mode |= HAL_LED_MODE_ON; /* Say it's on */
HalLedOnOff (led,HAL_LED_MODE_ON); /* Turn it on */
}
……
……
///////////////////////////////////
第四段代碼
void HalLedOnOff (uint8 leds, uint8 mode)
{
if(leds & HAL_LED_1)
{
if (mode == HAL_LED_MODE_ON)
{
HAL_TURN_ON_LED1(); //繼續追蹤下去,就找到對應的管腳,這裏就不多說了,先介紹到這自己搞定後面的
}
else
{
HAL_TURN_OFF_LED1();
}
}
……
……
}
本人,剛寫博客,這是我學習心得,有過之處望指出