FB_WriteAdsSymByName
The function block enables writing of any value to another controller using the symbol name.
On a positive edge at the bWrite input 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: Following each write procedure 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 sVarName, sNetID and nPort inputs do not change, the handle of the PLC variable will not be released after each write procedure. This mode should be used when values are exchanged very frequently.
VAR_INPUT
VAR_INPUT
bWrite : 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
bWrite: This function block writes the contents of the variable to which pointer nSrcAddr points into the variable sVarName of the selected ADS device.
sNetId: AMS NetID of the ADS device to which the value is to be transmitted. (Type T_AmsNetId)
nPort: AMS port number of the ADS device to which the value is to be transmitted. (Type T_AmsPort)
sVarName: Symbol name of the variable to be written on the selected ADS device (max 255 characters).
nSrcAddr: Address of the variable in which the value to written is located.
nLen: Length in bytes of the variable to be written.
tTimeout: Time until processing is aborted.
eComMode: Enum used to specify whether the handle of the PLC variable is released again after each write procedure.
VAR_OUTPUT
VAR_OUTPUT
bBusy : BOOL;
bError : BOOL;
nErrorId : UDINT;
END_VAR
bBusy: The transmission is active.
bError: An error occurred during the transmission.
nErrorId: ADS error number if an error has occurred.
Requirements
Development environment | required TC3 PLC library |
|---|---|
TwinCAT v3.1.0 | Tc2_DataExchange |