Siemens SIMATIC ET 200M Operating Instructions Manual page 145

• Then the IM 153-2 triggers a process interrupt.
• The master reacts with a diagnosis requirement to the slave.
• The IM 153-2 responds to this with a diagnostic frame. This diagnostic frame includes,
among other things, the number of the data record that includes the time-stamped
messages.
• Because of this diagnostic frame the associated run level "process interrupt" is launched in
the user program. Within this run level, the user must be able to tell which data record is
to be read with messages from the IM 153-2. Depending on the application case, the user
must also ensure multiple calls on this run level.
In your CPU´s manual, look up DPV1-blocks, e.g. "RALRM".
• The user program monitors entries in the run level "process interrupt". As soon as an entry
is detected, the data record is read from the IM 153-2. A block in accordance with DPV1
also serves to do this.
Refer to DPV1-blocks, e.g. "RDREC" in your CPU´s manual.
• In accordance with the requirements of your application, the data record is saved or
further processed. Every single signal message comprises 12 bytes, a data record can
include up to 20 messages.
Order of events
Figure 8-13
ET 200M
Operating Instructions, 04/2022, EWA-4NEB7806006-09
Processing time-stamped signals
8.2 Time stamping the input signals with IM 153-2
Functions
145