此文档是对UC/OS-II中的任务同步和通信进行的说明，包括信号量，邮箱，消息队列，信号量集进行了详细的介绍。-This document is a descr iption of the UC/OS-II task synchronization and communications, including semaphores, mailboxes, message queues, semaphore sets were introduced in detail.