General Specification Electrical Function gmw3110 General Motors Local Area Network Enhanced Diagnostic Test Mode Specification

8.4.6 Node Interface Function. 
8.4.6.1 Node Interface Data Dictionary (Table 74). 
Table 74: Node Interface Data Dictionary of InitiateDiagnosticOperation Service Pseudo Code 
Variable/Meaning 
Values 
message_data_length 
Security_Access_Unlocked 
Security_Access_Allowed
Reference Common/Global 
Pseudo Code Data 
Dictionary For Definition Of 
These Flags/Variables 
8.4.6.2 Node Interface Pseudo Code. 
Powerup States: 
None 
The following logic is executed when a request message with ServiceId $1A is received by the ECU: 
BEGIN FUNCTION Serv_1A_Msg_Recvd() 
IF (message_data_length != 2) THEN 
send Negative Response ($7F $1A $12) /*Invalid Format */ 
ELSE 
IF (($dataIdentifier is NOT supported) OR ($dataIdentifier requires security access AND 
Security_Access_Unlocked = FALSE) OR ($dataIdentifier requires security code AND 
Security_Access_Allowed = FALSE)) THEN 
send Negative Response ($7F $1A $31) /* Request Out Of Range */ 
ELSE IF (ECU long term conditions prevent retrieval of the data) THEN 
send Negative Response ($7F $1A $22) /* ConditionsNotCorrect */ 
ELSE 
--``,,``````,``,,``,,,`,`,`,,-`-`,,`,,`,`,,`---
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GMW3110 
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IF (device cannot respond with block contents within P2
C
ms) THEN 
send Negative Response ($7F $1A $78) /* RequestCorrectlyReceived-ResponsePending */ 
ENDIF 
/*Get data values from memory address associated with the $dataIdentifier*/ 
send ($5A $dataIdentifier $Data) /* send response message with DID data */ 
ENDIF 
ENDIF 
ENDFUNCTION