Blacklisting and whitelisting

With version 1.12, it is possible to use black or whitelisting for PLC symbols. With black or whitelisting, PLC symbols can be explicitly hidden or shown for use in the HMI. For this, you can tag the corresponding variables in the PLC with an attribute pragma. In the default case, blacklisting is active, which means that you have access to all variables of the PLC that are not explicitly hidden for the HMI. On the configuration page of the ADS extension, you can switch between black and whitelisting (Use whitelisting).

Blacklisting and whitelisting 1:

The following attribute pragmas are available for black or whitelisting in the TwinCAT HMI:

{ attribute 'TcHmiSymbol.Show' }
{ attribute 'TcHmiSymbol.ShowRecursively' }
{ attribute 'TcHmiSymbol.Hide' }
{ attribute 'TcHmiSymbol.ReadOnly' }
{ attribute 'TcHmiSymbol.BLOB' }

Use:

Blacklisting and whitelisting 2:

Blacklisting overrides whitelisting.

With blacklisting, all variables are visible in the HMI, except variables with the attribute TcHmi-Symbol.Hide.

With whitelisting, no variables are visible in the HMI except variables with the attributes TcHmiSymbol.Show and TcHmiSymbol.ShowRecursively.

Blacklisting and whitelisting 3:

Available from version 1.12.