USB Type-C协议规范，分享给需要的童鞋，USB Type-C Specification Release 1.3

ISO14443 TYPE B协议的RFID读卡器设计

This standard describes the use of the DisplayPort protocol between devices that support the USB Type-C connector using USB Type-C to USB Type-C Cable Assemblies. It describes cable assemblies that adapt the USB Type-C connector to Legacy DisplayPort connectors. It describes cable assemblies and adapters to adapt DisplayPort on USB Type-C to other video protocols. It describes the simultaneous use of USB Enhanced SuperSpeed and the DisplayPort protocol on the USB Type-C connector for docking applications. This standard describes the USB Type-C connector pin assignments and DisplayPort signaling rates to be used in various scenarios when using the above cable assemblies and adapters. It describes how the USB-PD Alternate Mode Discovery and Entry Processes are applied to DisplayPort on the USB Type-C connector.

usb-if官网的type-c 协议手册，里面包括 PD 、BC1.2、USB3、Emarker等补充资料。

本文设计了一款支持 PD3.0 的 E-Mark 芯片中的发送端（Transmitter, TX） 部分，它的主要作用是传输 Biphase Mark Coding（BMC）信号，协议中对输出 的信号的斜率及输出的高低电平的范围有严格的要求，并且对 TX 部分电路在奈 奎斯特频率下的输出阻抗的范围作了限制。