[Dcm] Vehicle Diagnostic Communication Part 62 [Simulation 1]

[Dcm] Vehicle Diagnostic Communication Part 62 [Simulation 1]車両診断通信
[Dcm] Vehicle Diagnostic Communication Part 62 [Simulation 1]

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In this article, I will explain the AUTOSAR-Dcm for the simulation of AUTOSAR-Dcm.


AUTOSAR-Dcm simulation configuration

Now that I have explained the necessary services, let’s review the AUTOSAR-Dcm simulation configuration again.

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See below for a detailed explanation.

The structure is supposed to be a combination of r3.x and r4.x systems, like an illegal building, but there should be no need to be so vigilant.
(Is it too much to ask you not to be alarmed?)


Items to check in an AUTOSAR-Dcm simulation

By the way, do you remember the services to be performed in an AUTOSAR-Dcm simulation?
I think I showed you the following table before.

DiagnosticSessionControl$10Diagnostic session control
SecurityAccess$27Security unlocking
TesterPresent$3ENotification of the presence of an off-board tester. (Used for session keeping, etc.)
ReadDataByIdentifier$22Reading of the current value of the record identified by dataIdentifier
WriteDataByIdentifier$2EWriting of the record identified by dataIdentifier

The relevant article is below.

A brief summary is as follows.

  • TesterPresent(Service$3E)
    • also check for presence of suppressPosRspMsgIndicationBit
  • ReadDataByIdentifier(Service$22)
    • also checks for multi-DID
  • WriteDataByIdentifier(Service$2E)
    • SessionControl(Service$10)/SecurityAccess(Service$27) also checked
    • Also check S3 time
  • Check ResponsePending
    • Also check responsePendingCount

Now you may be thinking, “What is responsePendingCount?”.
To be sure, I will not explain this.

It is not specified in ISO14229-1, but in practice, the number of possible replies to NRC$78 (ResponsePending) is often specified.
This specification is also in AUTOSAR-Dcm, so it’s a good time to check this as well.

It’s not a complicated matter.
Just change one parameter and see how it behaves.



  • AUTOSAR-Dcm simulation configuration review.
  • Review of services used in AUTOSAR-Dcm simulation.
    • Listed specific items to be checked.
    • Will also include confirmation of responsePendingCount, the number of times NRC$78 replies are received.

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