ReadUserDataBuffer

This function is for reading data contained in the User Data field of the currently enabled factory communication protocol. The referenced Buffer data structure, which is created by a FormatInputBuffer function, defines how the received data is interpreted.

Parameter Description
Event

Specifies the update event on which to read data.

This parameter needs to be a reference to any event with a timestamp , for example an AcquireImage function.
Buffer Specifies a reference to a Buffer data structure created by a FormatInputBuffer function, which defines how the received data is interpreted.
Protocol

Specifies which protocol the user data needs to be read from.

1 = EtherNet/IP Specifies that EtherNet/IP is the enabled factory communication protocol.
2 = PROFINET Specifies that PROFINET is the enabled factory communication protocol.
3 = SLMP Protocol Scanner Specifies that SLMP is the enabled factory communication protocol.
4 = Modbus TCP Server Specifies that Modbus TCP is the enabled factory communication protocol.
100 = Default Specifies that the currently enabled factory communication protocol is used. If more than one protocol is enabled, the first enabled protocol is used.
Validate Connection Specifies whether the function attempts to validate the connection. If enabled, the function returns #ERR if the selected protocol does not have an active cyclic connection.
Byte/Word Order

Specifies the bit order for words and bytes read by the function.

0 = Big endian Specifies that the most significant byte is stored first and subsequent bytes are stored in descending order.
1 = Little endian Specifies that the least significant byte is stored first and subsequent bytes are stored in ascending order.
2 = Big endian with 16-bit word swapping Big endian byte style is applied and double word types have their word pair order switched. (16-bit words)
3 = Little endian with 16-bit word swapping Little endian byte style is applied and double word types have their word pair order switched. (16-bit words)
100 = Default The default setting is used.
Returns

A UserData data structure containing the data sent by a client; or #ERR:

  • If any input parameters are invalid
  • If a connection from a client has not been established

  • If the data buffer has not been written to since establishing the connection
Results Data in the UserData data structure is accessed using the GetBufferData function. For more information, see the Input/Output topic.