
USB协议定了多种类型的包,有令牌包、数据包和握手包,特殊包。
根据PID可将USB2.0的包分为四种包类型。

SOP + SYNC +PACKET +EOP
The format of the IN, OUT, and SETUP Token packets is shown in Figure 1
令牌包格式:in ,out,setup

The format of the SOF packet is shown in Figure 2. ---------sof packet 格式

high speed sof的eop是5B=40bit,高速sof 总的字节数是12B=96bit
The format of the Data packets is shown in Figure 3. ---------------数据包格式

Lastly, the format of the Handshake packets is shown in Figure 4.-----------握手包格式
