4 16, 2019
2019年4月3日，USB-IF协会发布了USB PD3.0的更新，其中一个ECN是“USB PD R3.0 V1.2 ECN Cable Plug Get_Manufacturer_Info Clarification”，苹果MacBook 2018笔记本电脑不能点亮PD3.0显示器的事件作了澄清和说明。
The change is intended to explicitly define the response from a cable plug when the Get_Manufacturer_Info request is not supported. As a reminder, Get_Manufactuerer_Info is an extended message, and support for it is Optional. Refer to Table 6-67 Applicability of Extended Messages.
Current Spec simply states that support for Get_Manufacturer_Info is “Recommended” but it does not explicitly define how a cable plug should respond when this feature is not supported. “Ignore” behavior is implied and current Power Delivery compliance tests are consistent with this line of reasoning. The improvement in this case is to clarify any ambiguity by explicitly defining the response.
The Get_Manufacturer_Info (Get Manufacturer Info) Message is sent by a Port to request manufacturer specific information relating to its Port Partner or Cable Plug or of a Battery behind a Port. The Port Shall respond by returning a Manufacturer_Info Message (Section 6.5.7) containing a Manufacturer Info Data Block (MIDB). Support for this feature by the Cable Plug is Optional Normative.