ST_IotMqtt5Connect

Connection settings for the MQTTv5 client, which can be set at the function block FB_IotMqtt5Client. Through these settings, the client can transmit information to the message broker about potential restrictions, for example, a maximum packet size that the client can receive.

Syntax

Definition:

TYPE ST_IotMqtt5Connect :
STRUCT
    nSessionExpire     : UDINT;
    nMaxPacketSize     : UDINT;
    nReceiveMax        : UINT;
    nTopicAliasMax     : UINT;
    bReqResponseInfo   : BOOL;
    bIgnoreProblemInfo : BOOL;
END_STRUCT
END_TYPE

Parameter

Name	Type	Description
nSessionExpire	UDINT	Specifies the time in seconds after which a message broker deletes a client session if the client is not connected.
nMaxPacketSize	UDINT	With this setting the client tells the message broker up to which size in bytes it wants to or can receive messages. When a larger message is received, the client terminates the connection.
nReceiveMax	UINT	This setting determines how many QoS 1 or QoS 2 messages may be communicated to the client simultaneously. Simultaneous in the case means that the handshake (two- or four-step) happens at the same time.
nTopicAliasMax	UINT	Specifies the highest value a Topic Alias may have to limit the number of Topic Aliases existing at the same time. If the value is 0, it means that the client does not accept Topic Aliases.
bReqResponseInfo	BOOL	If the value is TRUE, then the message broker may send information in the CONNACK response. If the value is FALSE, the message broker does not send any response information.
bIgnoreProblemInfo	BOOL	If the value is TRUE, then the message broker may send a Reason String or User Properties with each packet. If the value is FALSE, the message broker may