Страница 1 мировой engineering стандарты общая спецификация

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GM WORLDWIDE ENGINEERING STANDARDS
GMW3110
Note: 
Services $10, $27, and $3B are optional and may not be present based on the type of ECU.
Note: 
The pseudo code flag Service_28_MsgReceived is used by the Boot_Process_Recv_Msg( ) function,
the Boot _28_Msg_Recvd( ) function, and the Boot_Exit_Diagnostic_Services( ) function to illustrate enabling
of the special case diagnostic CAN Identifiers used by SPS_TYPE_C ECUs.
9.3.2.5 Security Requirements. 
All programmable ECUs that have emission, safety, or theft related features
shall employ a seed and key security feature, accessible via the SecurityAccess ($27) service, to protect the
programmed ECU from inadvertent erasure and unauthorized programming from the GMLAN interface. All
field service replacement ECUs that meet the above criteria, shall be shipped to the field with the security
feature activated (i.e., a programming tool cannot gain access to the ECU without first gaining access through
the SecurityAccess service).
All ECUs that support security for SPS shall implement the seed and key relationship supplied by GM Service
and Parts Operations. Once a security algorithm is assigned, a change to the algorithm shall result in a change
to the ECU Base Model Part Number. See DID $CC in Appendix C of this specification.
Note: 
A change to the security algorithm shall also result in a change to the utility file needed to program the
ECU.
All development ECUs shall use the ones-complement of the seed as the valid key.
9.3.2.6 The Vulnerability Flag And Manufacturers Enable Counter (MEC). 
The Manufacturers Enable
Counter (MEC) and Vulnerability Flag are variables which are used to bypass a nodes security system during
development or during portions of the node and vehicle manufacturing process. The variables
manufacturers_enable_counter and vulnerability_flag are used in the pseudo code of the applicable diagnostic
services described within this specification to represent the MEC and Vulnerability Flag respectively.
Reference the SecurityAccess ($27) service within this specification for more information on accessing node
security.