Micromod Micro-DCI: 53MC5000 PLC AND PRINTER INTERFACES - Manual (Page 85)

7.0 SIEMENS S5 MODE
7.1 PURPOSE
The Siemens interface application permits data transfers between the Process Control Station
(PCS) and a Siemens Programmable Logic Controller (PLC) via the 3964 protocol. The PCS sup-
ports the following commands for both read and write operations:
1. D - Data Block
2. A - Absolute Address
The PCS supports the following commands for read-only operations:
3. Z - Counter Locations
4. E - Input Bytes
5. A - Output Bytes
6. M - Flag Bytes
The Data Block and Absolute Address commands handle data in 16 bit words and can be used for
L- and/or C-type data. L-data quantities must be even numbers (odd numbers will be decremented
by one). The Counter Locations command reads data in 16 bit words. The upper 6 bits are
masked out and the resulting 10 bit words are handled as C-type data. The remaining three com-
mands handled data in bytes and can only be used with L-type data.
The maximum data transfer in either direction is 128 bytes, which corresponds to 64 PCS L-bytes
and 32 PCS C-words.
7.2 INSTALLATION CONFIGURATION
As shown in Figure 7-1, communication between the PCS and Siemens PLC is point-to-point.
Figure 7-1. Point-to-Point Installation Configuration
53MC5000
PCS
RS-232/485
ITB SIEMENS
PLC
COMPLEX
Section 7. Siemens S5 Mode
SIEMENS
7-1