Specifications

113
Technical Description Section 13-2
13.1 General Information
The operating terminals allow for a simple connection to the Klöckner Moeller PLCs
PS 4-201.
The operating terminal is connected to the PU interface of the PLC. The data traffic
on the interface is handled by the SUCOM1 protocol.
The software components of the system are fully adapted to the parameters and
marginal conditions of the SUCOM1 protocol.
This offers the user the following advantages:
- Random read and write access to all flags within the PLC. Data of existing PLC
programs can be displayed and modified directly in the operating terminal. It is
not necessary to adapt the PLC program to the operating terminal in any respect
because it is not required that communications data are stored in a specified
address area or data type area.
- The operating terminal automatically polls the freely definable data areas for
cyclic data.
- No additional configuration effort required within the PLC.
- Minimal increase of the cycle time of the PLC.
- The protocol provides error control. Transmission errors are detected and, if
possible, eliminated by repeating the transmission.
- The parameters of the interface SER1 are stored in the application description.
Modifying of these parameters is possible in the setup mask or each other I/O
mask of the terminal at any time.
- The programming system provides a maximum of support to the user in pro-
gramming the operating terminal. The definitions (abbreviations) used here are
identical with the definitions used within the PLC program.
13.2 Technical Description
The connection of the operating terminal to the Klöckner Moeller PLC is effected by
means of the SUCOM1 programming protocol.
The SUCOM1 protocol allows random read and write access to all flags of the PLC.
All data types can also be accessed in bit-mode. The size of the address area
depends on the respective PLC.
A read access to the addressed word must occur, before individual bits can be
accessed for a write operation. During these accesses, care must be taken to en-
sure that neither the terminal nor the PLC modify individual bits of the same word.