各位高手,小弟正在基于MSP432單片機(jī)及UC/OS-III開發(fā)應(yīng)用。實(shí)現(xiàn)的功能是使用信號量控制串口發(fā)送數(shù)據(jù)。創(chuàng)建了信號量,初始化為0,串口任務(wù)中等待信號量。單步調(diào)試執(zhí)行到OSSemPend的時(shí)候,發(fā)現(xiàn)任務(wù)并沒有掛起等待,而是繼續(xù)執(zhí)行后面的語句。請教各位高手其中的原因。謝謝!串口發(fā)送任務(wù)代碼如下: staticvoid App_TaskUART(void *p_arg) { OS_ERR os_err; CPU_BOOLEAN SemFlag; (void)p_arg; while (1) { SemFlag = BSP_OS_SemWait(&SEM_UARTTX , 0); if(SemFlag == DEF_OK) { MAP_UART_transmitData(EUSCI_A2_BASE , UARTTXData); } OSTimeDlyHMSM(0u , 0u , 1u , 0u , OS_OPT_TIME_HMSM_STRICT , &os_err); } } CPU_BOOLEAN BSP_OS_SemWait (BSP_OS_SEM *p_sem , CPU_INT32U dly_ms) { OS_ERR err; CPU_INT32U dly_ticks; dly_ticks = ((dly_ms *DEF_TIME_NBR_mS_PER_SEC) / OSCfg_TickRate_Hz);/*將毫秒級延時(shí)轉(zhuǎn)換為滴答數(shù)*/ /*等待接收信號量*/ OSSemPend((OS_SEM *)p_sem, (OS_TICK )dly_ticks, (OS_OPT )OS_OPT_PEND_BLOCKING, (CPU_TS )0, (OS_ERR *)&err); if(err != OS_ERR_NONE) { return (DEF_FAIL); } return (DEF_OK); }
|