Link Layer Clause Samples
The Link Layer clause defines the responsibilities and protocols governing the transmission of data between directly connected network devices. It typically outlines how devices establish and maintain communication links, manage data framing, and handle error detection at the physical connection level. By specifying these operational details, the clause ensures reliable and orderly data exchange across the network's foundational layer, thereby minimizing transmission errors and supporting overall network stability.
Link Layer. Physical layer Coder params:
Link Layer. The <I> operator interface communications port is configured as a slave station with programmable station ID. The customer’s DCS computer is assumed to be the master station requesting data from or sending data to the turbine control. Since multiple slave stations are allowed on the link, the turbine control port will send data upon request only. No periodic transmission of data is possible. A maximum of eight units may be connected over one MODBUS link when multi–unit <I> functionality is implemented; one or two units for this protocol is recommended. The MODBUS protocol consists of a set of messages initiated by the master station. Each message contains an address indicating which slave station is to respond (broadcast messages are possible), a message code, the data and a CRC checksum. The transmission mode is RTU (Remote Terminal Unit), and the ASCII mode is not supported.