Subscription

You can use the Subscription method to request OCA objects, generate notifications for value changes, or set up sending of notifications. If the method was executed successfully, the result is output in the property stSubscribed.

	Cyclic method call Since several PLC cycles may pass between sending and the response from the device, this method should be executed cyclically.

Syntax

VAR_INPUT
   pLink           :  POINTER TO ST_Link; 
   bExecute        :  BOOL; 
   eMode           :  E_SubscriptionMode;
   nSubscribtionNo :  UDINT;
   eCmdMode        :  E_OcaMessageTypeCmd;
END_VAR

Inputs

Name	Type	Description
pLink	POINTER TO ST_Link	Pointer for establishing a connection between OCA objects and the OCA device
bExecute	BOOL	The method is executed with a positive edge at the bExecute input.
eMode	E_SubscriptionMode	Depending on whether a notification request is to be created or deleted, the input of the method can be set to E_SubscriptionMode.ADD_Subscription or E_SubscriptionMode.DELETE_Subscription.
nSubscribtionNo	UDINT	Unique number for localizing the respective subscription
eCmdMode	E_OcaMessageTypeCmd	Depending on whether confirmation is required or not, this input variable is set to E_OcaMessageTypeCmd.OcaCmdRrq or E_OcaMessageTypeCmd.OcaCmd.