Mode Of The Cpu - Effect On The Cm - Siemens CM 1542-5 Operating Instructions Manual

Note
PROFIBUS interface
The CM provides no 24 VDC power supply on the PROFIBUS interface. I/O devices (for
example, PC adapter 6ES7972-0CB20-0XA0) are therefore not operational on the interface).
3.4

Mode of the CPU - effect on the CM

You can change the mode of the CPU between RUN and STOP using STEP 7 or the switch.
Depending on the operating status of the CPU, the CM behaves as described below.
Changing the CPU from STOP to RUN
● Programmed connections are established.
● In DP master mode:
– Change from CLEAR to the OPERATE mode
● In DP slave mode:
– Going diagnostics interrupt to the master
– Current input data is transferred.
Changing the CPU from RUN to STOP
The reaction is as follows in STOP:
● Programmed connections are terminated.
● In DP master mode:
Change to the CLEAR mode
● In DP slave mode:
– Input data is sent to the DP master with the value "0" and a DP diagnostics alarm is
● Regardless of the mode, the following functions remain enabled:
– The configuration and diagnostics of the CM
– Data record routing
– S7 routing function
– Time-of-day synchronization
– Configured connections remain established.
CM 1542-5
Operating Instructions, 11/2018, C79000-G8976-C290-04
sent.
Relevant system connections for configuration, diagnostics and PG channel routing
still exist.
Installation, connecting up, commissioning, operation
3.4 Mode of the CPU - effect on the CM
25