Structure Of The Im 153-2 Messages - Siemens SIMATIC ET 200M Operating Instructions Manual

8.2.4.7

Structure of the IM 153-2 messages

The IM 153-2 makes available 15 data records for saving stamped input signals (signal
messages) and special messages (DS 100 to DS 114). A maximum of 20 signal and special
messages each consisting of 12 bytes can be saved in a data record.
Structure of the message frame header
Each message frame with a data record has 4 bytes of header data:
Table 8- 5
Byte
0
1
2
3
Structure of the signal message
A signal message can come from modules on the slots 4 to 11. It is structured as follows:
Table 8- 6 Structure of the signal message
Meaning
Slot number of the DI
module
Channel number of the DI
module
Signal status
Reserved
Time of the signal change 8 (2 DW)
ET 200M
Operating Instructions, 04/2022, EWA-4NEB7806006-09
Header data of the IM 153-2 message frame (example)
Contents Meaning
5Eh Read data record
00h IM 153-2 slot
64h Number of the data record (e.g. 100 dec.)
0Ch Number of the following bytes (e.g. 12 dec.)
Number of Remarks
bytes
1 Together with the channel number for addressing the digital signal
Range of values:
0 ... 3
4 ... 11
12 ... 255
1 Together with the slot number for addressing the digital signal
Range of values:
0 ... 15
16 ... 255
1 Bit 7
Bit 6 ... Bit 0
1 Unassigned
Time stamp in ISP-format
(refer to table below for structure)
8.2 Time stamping the input signals with IM 153-2
Unassigned
Slot number of the DI module
Unassigned
Channel number of the DI module
Unassigned
1: Signal incoming
0: Signal outgoing
Unassigned
Functions
153