Siemens simatic c7-621, Руководство пользователя

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04/99 Programming Preparations
Getting Started with C7-621-AS-i 17
Setting up a bit memory address area for clock memories
Clock memories are bit memories which periodically modify their binary value (pulse-pause ratio: 1:1).
You need these memories in the following programming example.
To enable you to set up the clock memory, you must make the following settings.
In the Hardware Configuration window open the dialog window Properties - C7-CPU621 by double-
clicking on the C7-CPU-621 icon.
In the dialog window displayed, click on the tab sheet Cycle / Clock Memory to select it.
Þ
Activate the
Clock Memory
checkbox and enter 10 for the number of the memory byte.
Each bit of the clock memory byte is assigned a period time/frequency:
Bit 7 6 5 4 3 2 1 0
Period time (s) 2 1,6 1 0,8 0,5 0,4 0,2 0,1
Frequency (Hz) 0,5 0,625 1 1,25 2 2,5 5 10
Confirm your entries with OK. To save the configuration, select
Station
→
Save and Compile
from the
menu bar.
To close the Hardware Configuration window select Station
→
Exit from the menu bar.
In the SIMATIC_Manager the folder C7 CPU621 containing the S7 program is created automatically. This
S7 Program folder in turn contains the folder Blocks with an empty organization block OB1.
Open each folder with a double click.