DataSourceState (ENUM) ¶ TYPE DataSourceState : InOut: Name Comment DS_New In this state only Initialize may be called DS_Initialized In this state only StartConnect may be called DS_Connecting While the driver is in this state, Connecting will be called. DS_Ready In this state, the driver is able to execute requests to its datasource. DS_Busy In this state, the driver currently is not able to execute requests to its datasource DS_ShuttingDown In this state only ShuttingDown will be called DS_Shutdown In this state the driver is shutdown and all allocated resources have been released DS_Error In this state the driver encountered an error that it cannot fix itself.

DataSourceTransactionResult (ENUM) ¶ TYPE DataSourceTransactionResult : InOut: Name TR_Ok TR_Pending TR_UnknownTransaction TR_Error

DriverInitConstants (GVL) ¶ InOut: Scope Name Type Initial Constant CustomerMask DWORD 16#FFFF0000 DriverMask DWORD 16#FFFF Customer_Standard WORD 16#0 Driver_Unknown WORD 16#0 Driver_Monitoring_Standard WORD 16#1 Driver_OPC_Standard WORD 16#2 Driver_SymbolicMonitoring_Standard WORD 16#3

DriverInitInfo (STRUCT) ¶ TYPE DriverInitInfo : STRUCT InOut: Name Type Comment dwDataTag DWORD identifies the kind of given initialization data dwDataVersion DWORD for extensibility of the init data dwDataSize DWORD size of the given data, correlated to dwDataVersion

ICallback (ITF) ¶ INTERFACE ICallback EXTENDS IGeneric -> IGeneric Methods: Callback GetInterface , inherited from IGeneric Structure: Callback (Method)

ICallback.Callback (METH) ¶ METHOD Callback InOut: Scope Name Type Comment Input pParam POINTER TO BYTE A generic parameter, depending on the specific callback

ICredentialsProvider (ITF) ¶ INTERFACE ICredentialsProvider EXTENDS IGeneric -> IGeneric Methods: GetCredentials IsGetCredentialsFinished LoginFailed StartGetCredentials GetInterface , inherited from IGeneric Structure: GetCredentials (Method) IsGetCredentialsFinished (Method) LoginFailed (Method) StartGetCredentials (Method)

ICredentialsProvider.GetCredentials (METH) ¶ METHOD GetCredentials : UDINT Must return ERR_OK if called after a successfull <see cref=”IsGetCredentialsFinished”> InOut: Scope Name Type Return GetCredentials UDINT Input udiRequestId UDINT Output stUserName STRING stPassword STRING

ICredentialsProvider.IsGetCredentialsFinished (METH) ¶ METHOD IsGetCredentialsFinished : UDINT Will return ERR_OK if the request is finished, ERR_PENDING if it is not yet finished, ERR_DS_RETRYLOGIN if the login should be tried again, another error code in case of an error InOut: Scope Name Type Return IsGetCredentialsFinished UDINT Input udiRequestId UDINT

ICredentialsProvider.LoginFailed (METH) ¶ METHOD LoginFailed : UDINT Will be called when a login failed due to wrong credentials The behaviour of the datasource afterwards depends on the return value. In case of ERR_PENDING, the logincycle will be started again with a call to GetCredentials. In all other cases the driver will go to it’s error state. InOut: Scope Name Type Comment Return LoginFailed UDINT Input udiRequestId UDINT Output udiRetryWaitTime UDINT The time that is waited until the next try to login is started