Siemens SIMATIC C7-621 Manual page 45

04/99
With this control program and the configuration that you loaded, you can initiate the messages on the
SIMATIC C7 device.
Control program
L MW20
T DB46.DBW4
The above figure shows the connection between the PLC and the OP when a message appears. The
process is described in detail below.
The information that, for example, the system was switched on must be evaluated in the user program.
This can be achieved, for example, by transferring the memory word MW20 containing the evaluated
information of the AS-i input data to the data block.
A bit area displays the current status of the messages. Each bit that is set indicates that there is a
message.
The area pointer which you have set at the beginning of the configuration "looks" cyclically in the bit
area, detects whether a bit is set there, and displays the associated message on the C7 display.
After transfer of the configuration to the C7-OP (as described earlier), press the ENTER key. The start
screen is displayed.
Switch the system on with the start switch on the control unit (make sure it is set to the initial position).
This triggers an individual message. The message level is displayed and the message appears.
Getting Started with C7-621-AS-i
:
:
:
:
:
:
Area pointer
DBX 4.7 .... 4.0 DBX 5.7 .... 5.0
16 8 7 6 5 4 3
Assigned message number
Bit area for messages
Plant ON
F1 F2 F3 F4
SF DC5V RUN
FRCE STOP
1 2 3 4
6 7 8 9
Configuring Event Messages
2 1
SIMATIC C7-621
F5
5
ESC
+/-
0
S H IF T
ENTER
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