BECKHOFF C1300 - Manual (Page 6)

C1300 VME to II/O Interface Unit Beckhoff II/O-System
Page 6 of 44 Version : 2.01 Date : 18.12.95
The connection of the II/O system to the host system is established by a DPRAM. This is
providing fast and comfortable communications.
The processing of the diverse signal states is supported by several II/O peripheral modules,
which are linked in a ring structure.The use of fiber optics minimizes the sensitivity for
interferences and allows a high transmission rate of 2.5 MBd. Errors, occuring in the FO--
ring, will be detected and reported to the host system by the central module. Functions
implemented for ring diagnosis, enable quick detection and correction of errors.
There is a speed and simplicity optimized communications protocol which, in the further
course of this documentation, will be called a telegram.
Communications on the FO-ring are controlled by the central module. This module will send
telgrams, that pass each of the modules in the FO-ring and are eventually received and
checked.