Siemens SIMATIC S7-300 FM 350-1, Руководство пользователя

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Operating Modes, parameters and commands
7.3 Count modes
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
107
Stopping the count using the gate stop function
You can also stop the count by setting the gate stop function, regardless of the status or
signals set at the SW gate. This is done by setting input parameter GATE_STP at
FC_CNT_CTL1.
When you reset this parameter, you can only retrigger the gate by setting a positive edge at
digital input DI-Start (HW gate), or you once again set input parameter SW_GATE.
Gate control in isochronous mode
SW gate control: To control the SW gate, you set and reset the SW_GATE control bit in the
user program. After the control bit has changed, the count starts and ends at time T
o
in the
next PROFIBUS DP cycle:
7
'3
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6:B*$7(
7
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7
'3
7
'3
7
'3
7
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7
L
7
L
7
L
3URYLVLRQRIDFWXDOFRXQWYDOXH
3URYLVLRQRIWKHFRXQWYDOXHWKDWZDVYDOLGDWWKHHQGRIWKHFRXQW
'3F\FOH '3F\FOH '3F\FOH '3F\FOH '3F\FOH
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Figure 7-15 Starting and stopping the count using the SW gate (SW_GATE)