Communication with LOGO! modules by Siemens

Logical modules LOGO! are suitable for both industrial usage and BMS systems. Examples of usage:
- Simple monitoring and control
- Building automation
- Remote monitoring and control of smaller machines
- Basic energi monitoring
- Location monitoring for logistics applications
- and many others

Communication with LOGO! 8 logical modules

The LOGO! 8 module (OBA8) supports Ethernet commnication by the S7 protocol.

For this communication in the PROMOTIC system can be used: PmS7 - Driver for communication by S7-TCP/IP protocol

For easy integration of this driver into the application it is handy to use:
Remarks concerning definition of variable address (definition of ItemId):
- The addresses in LOGO! modules start from 1, but in the S7 protocol addresses start from 0.
- Values in data areas (e.g. in I, Q, M areas, etc.) are of the Bit type, but in the S7 protocol these are of the Byte type (i.e. 8 LOGO! values can "fit into" a single S7 value). Therefore it is necessary to recount the LOGO! addresses when entering into S7 addresses. Example:
M1 -> M0.0
M8 -> M0.7
M9 -> M1.0
- LOGO! has the VM data area thet is also available in S7 in the DB1 datablock. Other areas can be mapped into this area:
Data area VM address - from VM address - to Range S7 address
I 1024 1031 8 Bytes I1 = DB1,X1024.0 = I0.0
AI 1032 1063 32 Bytes AI1 = DB1,W1032
Q 1064 1071 8 Bytes Q1 = DB1,X1064.0 = Q0.0
AQ 1072 1103 32 Bytes AQ1 = DB1,W1072
M 1104 1117 14 Bytes M1 = DB1,X1104.0 = M0.0
AM 1118 1245 128 Bytes AM1 = DB1,W1118
NetI 1246 1261 16 Bytes NetI1 = DB1,X1246.0
NetAI 1262 1389 128 Bytes NetAI1 = DB1,W1262
NetQ 1390 1405 16 Bytes NetQ1 = DB1,X1390.0
NetAQ 1406 1469 64 Bytes NetAQ1 = DB1,W1406
- Date and time can also be mapped into the VM area:
VM address Value Range S7 address
984 Diagnostic Bits Array 1 Byte DB1,B984
985 year 1 Byte DB1,B985
986 month 1 Byte DB1,B986
987 day 1 Byte DB1,B987
988 hour 1 Byte DB1,B988
989 minute 1 Byte DB1,B989
990 second 1 Byte DB1,B990

Communication with older logical modules than LOGO! 8

Older module types (LOGO! OBA6, LOGO! OBA7) do not support Ethernet communication by the S7 protocol.

For this communication in the PROMOTIC system can be used: OPC server.

OPC Server by Siemens:
- Name: S7-200 PC-Access V1.0.
- Follow these recommendations for the OPC server:
- install driver "PC Adapter USB A2 Driverdisk V1.0" - see
- run the OPC server as Administrator
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