BECKHOFF BK3000 - Manual (Page 34)

PROFIBUS coupler BK3xx0 in the PROFIBUS DP
34 BK3xxx/LC3100
All the inserted terminals have to be configured. Unused inputs and outputs
can be omitted from the address assignment in order to save address
space in the PLC.
“Double-clicking” on a field in the “Order number” column will cause a
menu to appear for the selection of the desired identification for the
corresponding inserted terminal.
The analogue channels provide an opportunity of inserting another byte in
addition to the 16 bits of user data. This byte is a control/status byte that
controls access to a 64-byte register set. This register can for example be
used to switch a thermocouple from type K to type S. The data word
containing the user data always takes the form of an IN/OUT word if the
control/status byte is used. Allocation of input and output addresses is
necessary to enable access to the registers.
The possible identifications are precisely described in the appendix and in
the descriptions of the particular terminals.
Ensuring data consistency The consistency of the data related to a station is secured by the Profibus
transmission protocol. Consistency over the whole process image is
achieved by activating the “SYNC” and “FREEZE” operating modes in the
masters.