Function Description

The READ_ASYN function is used to read 1 Kbyte of data via the asynchronous messaging channel of TSX ETY modules in TCP/IP mode.

The following data can be read-accessed:

  • internal bits,

  • internal words.

Asynchronous reading can only take place between two stations on the same Ethernet TCP/IP network segment.

The READ_ASYN function is sent at the end of the MAST task only if this is configured in periodic mode. It is possible to activate 8 functions simultaneously.

The operating principle is identical to that of the WRITE_ASYN function.

The size of the send and receive buffers is expressed in words. It is 512 words, or 1024 bytes.

NOTE: The asynchronous server function supports UNI-TE V1 or V2.0 protocols. The READ_ASYN function uses the UNI-TE V2.0 protocol.

The additional parameters EN and ENO can be configured.

FBD representation

Representation:

LD representation

Representation:

IL representation

Representation:

LD Address
READ_ASYN Object_Type, First_Object, Object_Number, Management_Param, Receiving_Array

ST representation

Representation:

READ_ASYN(Address, Object_Type, First_Object, Object_Number, Management_Param, Receiving_Array);

Parameter Description

The following table describes the input parameters:

Parameter

Type

Comment

Address

ARRAY [0.. 5] OF INT

Address of the destination entity of the exchange. Addresses are of the type: ADDR(’{Network.Station}SYS.

Object_Type

STRING

Type of objects to read:

  • ’%M’: internal bits,

  • ’%MW’: internal words,

  • ’%S’: system bits,

  • ’%SW’: system words.

First_Object

DINT

Index of the first object to read.

Object_Number

INT

Number of objects to read.

The following table describes the input/output parameters:

Parameter

Type

Comment

Management_Param

ARRAY [0.. 3] OF INT

Exchange management table

The following table describes the output parameters:

Parameter

Type

Comment

Receiving_Array

ARRAY [n... m] OF INT

Word table containing the value of the objects read.