FB_WriteAdsSymByName

The function block FB_WriteAdsSymByName enables writing of any value to another controller using the symbol name.

On a positive edge at the input bWrite the function block writes the value to which the pointer nSrcAddr points into the variable sVarName of the selected ADS device (e.g. PLC). The ADS device is indicated by the AMS-NetId (sNetId) and the AMS Port number (nPort).

The internal mode of operation of the function block can be changed with the aid of the eComMode input:

eComMode := eAdsComModeSecureCom: After each write process, the handle of the PLC variable is released again. This mode should be used when values are exchanged very slowly.
eComMode := eAdsComModeFastCom: As long as the inputs sVarName, sNetID and nPort do not change, the handle of the PLC variable is not released after each write operation. This mode should be used when values are exchanged very frequently.

Inputs

VAR_INPUT
    bRead            :  BOOL;
    sNetId           :  T_AmsNetId;
    nPort            :  T_AmsPort := 851;
    sVarName         :  STRING(255);
    nSrcAddr         :  PVOID;
    nLen             :  UDINT;
    tTimeout         :  TIME := DEFAULT_ADS_TIMEOUT;
    eComMode         :  E_AdsComMode := eAdsComModeSecureCom;
END_VAR

Name	Type	Description
bWrite	BOOL	This function block writes the contents of the variable to which pointer nSrcAddr points into the variable sVarName of the selected ADS device.
sNetId	T_AmsNetID	AMS NetID of the ADS device to which the value is to be transmitted.
nPort	T_AmsNetID	AMS port number of the ADS device to which the value is to be transmitted.
sVarName	STRING(255)	Symbol name of the variable to be written on the selected ADS device (max. 255 characters).
nSrcAddr	PVOID	Address of the variable in which the value to written is located.
nLen	UDINT	Length in bytes of the variable to be written.
tTimeout	TIME	Time until processing is aborted.
eComMode	E_AdsComMode	Enum used to specify whether the handle of the PLC variable is released again after each write process.

Outputs

VAR_OUTPUT
    bBusy     :  BOOL;
    bError    :  BOOL;
    nErrorId  :  UDINT;
END_VAR

Name	Type	Description
bBusy	BOOL	The transmission is active.
bError	BOOL	An error occurred during the transmission.
nErrorId	UDINT	ADS error number if an error has occurred.

Requirements

Development environment	required TC3 PLC library
TwinCAT v3.1.0	Tc2_DataExchange