檢視帧定界的原始碼

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|<center>'''帧定界'''<br><img
src=" https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fp9.qhimg.com%2Fdr%2F200_200_%2Ft010805d1c51e33a96c.jpg&refer=http%3A%2F%2Fp9.qhimg.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=auto?sec=1656756380&t=1639d0580d8fc06d6ce021c45da3e297" width="280"></center><small>  圖片來自百度</small> 
|}
'''帧定界'''就是标识帧的开始与结束，目的是让接收方能从接收到的[[二进制]]比特流中区分出帧的起始与终止。
异步通信中以帧作为发送单位，接收端必须随时做好接收帧的准备。这时，[[帧]]的首部必须设有一些特殊的比特组合，使得接收端能够找出一帧的开始，这种方式称为帧定界，也称为“[[帧同步]]”。协议不同，帧的长短和结构也有差别,但无论如何必须对帧进行定界。

*中文名:[[帧定界]]

*特    点:字节计数法

*类    型:以帧作为发送单位