Libraries
There are a number of libraries for the Bus Terminal Controllers (Bus Couplers with PLC functionality, named BCxxxx) (see the TwinCAT InfoSys).
TwinCAT PLC Library: System BC
The library contains function blocks for access to the Bus Terminal Controller's (BCxxxx) system functions.
TwinCAT PLC Library: Utilities BC
The library contains useful function blocks for the Bus Terminal Controller (BCxxxx). In addition to the RTC blocks, the library contains a function block for decoding the DCF-77 time signal, along with a number of conversion functions. Internally, the Bus Terminal controller's system functions are called.
TwinCAT PLC Library: Helper BC
The PlcHelper.lb6 library contains a number of functions which provide direct access to memory areas in the Bus Terminal Controller's (BCxxxx) PLC runtime system.
TwinCAT PLC Library: ADS BC
The library contains function blocks for acyclic client-server communication between a BC9xxx Bus Terminal Controller and other ADS devices in the network. The way in which these function blocks operate is not significantly different from that for the PLC runtime system on the PC.
TwinCAT PLC Library: Event driven BC transmission blocks
The present function blocks simplify event-driven data exchange between the Bus Terminal Controllers and/or other ADS devices (TwinCAT NC, Bus Terminal Controllers, ...).
The FB_WriteXXXOnDelta() function blocks implement a write procedure when the input signal rises above or falls below a specified limit value. The frequency with which the input signal is examined can be set. Event-driven data writing minimizes the loading on the fieldbus. If an error occurs during transmission, the process is repeated until the connection is established once more. All data types supported in the TwinCAT PLC are permitted as source and target variables. Symbol names are also supported.
Watchdog function blocks are available to monitor individual communication partners. The device that is to be monitored cyclically transmits an incrementing counter. A check is made at the receiver to see that the counter state changes within a specific time.
TwinCAT PLC Library: ModbusTCP BC
The library contains function blocks that permit the exchange of data between the Bus Terminal Controller (BC9xxx) and a remote partner on the MODBUS/TCP port.
TwinCAT PLC Library: SMTP BC
The library contains useful function blocks for the Bus Terminal Controller (BC9xxx) for use of the SMTP protocol (Simple Mail Transfer Protocol).