C1220-000 | PC interface card

The Beckhoff Lightbus is coupled to the host System via a DPRAM, thus guaranteeing fast and convenient communication.

Bus couplers for Beckhoff Bus terminals and diverse I/O modules are

available for processing the process image. Modules and bus couplers are linked to one another in a ring structure. Thanks to the use of fibre-optic conductor, interference sensitivity is low and the data transfer rate of 2.5 Mbaud is high. Errors occurring in the fibre-optic ring are detected by the central module and are reported to the host system. Implemented ring diagnostics functions enable swift error detection and remedying.

A communication protocol optimized for speed and simplicity has been defined for data transfer between the central module and I/O modules.

Below, this communication protocol is also referred to as a telegram.

Communication on the fibre-optic ring is controlled by the central module. It sends telegrams which pass through the individual modules and terminal rows in the fibre-optic ring, and which are ultimately received again andchecked.

A telegram consists of the telegram frame and contents.

Technical Data

Interface processor: Siemens SAB 80C166-S

Data connection: Beckhoff Lightbus

Data transfer rate: 2,5 MBaud, 32 Bits of user information in 25µsec

Supply voltage: 5 V

Current consumption: 800 mA

Dimensions: 161mm x 107mm