Extensions.DiagCom.GetComChannel

Classification

Name	GetComChannel
Short Description	Represents a connection to the control unit at runtime
Class	Term
Extension	OTX DiagCom extension
Group	ComChannel related terms
Exceptions	UnknownTargetException LossOfComException
Checker Rules	DiagCom_Chk100 DiagCom_Chk101
Standard Compliant	Yes

OTL Syntax

ComChannelTerm = DiagCom.GetComChannel(StringTerm, StringTerm, BooleanTerm);

Description

GetComChannel is a term to create a new communication channel to an ECU. The communication channel represents a connection to only one control unit (Logical Link).

To create a connection to the ECU, the following rules are applied:

• The ComChannel is created at the time this term is executed.
• If the ComChannel already exists, no additional action is carried out by the execution of this term.
• The ComChannel is created when it is first needed for actual diagnostic communication.

No matter which approach is chosen, the term GetComChannel shall always return a handle to the same ComChannel for a given ECU. It is possible to manually control the lifecycle of a ComChannel object by closing a ComChannel handle using the CloseComChannel action. The OTX runtime environment will clean up all opened ComChannel handlesat the end of a diagnostic session.

Important: Long-time running procedures should note that the OTX runtime will close open ComChannels (see GetComChannel) solely via the CloseComChannel activity! This has an impact on the long-time stability of the runtime environment. To avoid memory leaks, ComChannels should not be opened implicitly, like ExecuteDiagService(CreateDiagServiceByName(GetComChannel("LL_AirbaUDS","",false), "DiagnServi_ReadDataByIdentECUIdent"), ...); because the resources cannot be released until the completion of runtime execution. Better use: ComChannel comChannel = GetComChannel("LL_AirbaUDS","",false); DiagService diagService = CreateDiagServiceByName(comChannel, "DiagnServi_ReadDataByIdentECUIdent")); ExecuteDiagService(diagService, ...); ... CloseComChannel(comChannel); For the short-dated execution of procedures, this is of minor importance!

An ECU variant selection can be performed, see below.

Return Value

The Term returns the value, see table below.

In OTX, Terms are categorized according to its return data type!

Data Type	Description
ComChannel	Returns a handle to the ComChannel for a given ECU

Properties

Name	Data Type	Class	Default	Cardinality	Description
Identifier	String	Term	-	[1]	This element represents a string identifying the communication channel which shall be created. In case a MVCI/ODX system is used the identifier specifies the SHORT-NAME of the MCDLogicalLink to be used for communication.
EcuVariantName	String	Term	""	[0..1]	This optional element allows an OTX sequence to explicitly specify a particular ECU variant that the ComChannel shall be associated with. In case a MVCI/ODX system is used the <ecuVariantName> element specifies the SHORT-NAME of the MCDDbEcuVariant to be associated with the logical link.
PerformVariantSelection	Boolean	Term	false	[0..1]	This optional element can be used by the OTX author for controlling whether an implicit variant selection shall be done.

ECU variant selection

An ECU variant selection can be performed after opening the channel and returns a handle to the selected ECU-Variant. The variant identification functionality also exists as a separate action called IdentifyAndSelectVariant.

EcuVariantName	PerformVariantSelection
Empty	False	No ECU variant selection is performed
Empty	True	An ECU variant selection is performed for the BaseVariant descriped in Identifier
NotEmpty	True	An ECU variant selection is performed. The channel is created to point at the desired ECUVariant and variant selection is performed on the link afterwards.

OTL Examples

DiagCom.ComChannel ComChannel1;

/// Flow

ComChannel1 = DiagCom.GetComChannel("LL_GatewUDS", "EV_GatewLear_006", false);

See also

GetComChannelIdentifierFromResponse
GetComChannelEcuVariantName
IsVariant
ExecuteDiagService