Siemens SIMATIC S5 IP 281 Equipment Manual page 119

6.4.5 Starting Counter2 When the Interrupt Value of Counter 1 Is Reached (SC2A)
Method of Counter 2 is started when both of the conditions below are met.
operation
– Counter 1 reaches the interrupt value.
– The gate of counter 2 (gate 2) is open.
When counter 1 reaches the interrupt value, the gate function appropriate
to the autonomous operating mode set takes effect for counter 2.
Closing of gate 2 (also EMERGENCY OFF gate stop) stops counter 2 and
blocks gate function 2. The gate function does not take effect again for
counter 2 until interrupt value 1 is reached again.
Counter 1 reaches in-
Example
terrupt value.
Herdwere gate 2 or
software gate 2
Internal gate 2
Counter 2
Gate control Counter 1:
Counter 2:
Load counter Counter 1:
Counter 2:
Read counter All read capabilities are permitted (+ section 6.5.3).
Digital output All methods of operation are permitted (+ section 6.7).
All interrupt settings are permitted (+ section 4.4).
Interrupt
The interrupt value of counter 1 is provided with a hysteresis of~l
Special
notes
The interrupt at the gate start is also triggered when the interrupt value of
counter 1 is not yet reached (i.e., the interrupt is exclusively dependent on
the hardware or software gate).
AG 1992, Order No: 6ES5 998-0KP21
Operating Modes and Functions
– Gate functions specified by the autonomous
operating mode set
– All gate functions described in section 6.6
– Same as counter 1 except that the gate function
must be enabled by reaching the interrupt value
of counter 1
All load capabilities described in section 6.5.1 are
permitted.
Only practical via LOS bit in control register 2
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