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

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Operating Modes, parameters and commands
7.5 Triggering of a Hardware Interrupt
FM 350-1 Counter module
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Manual, 05/2011, A5E03648639-01
7.5 Triggering of a Hardware Interrupt
Introduction
With the FM 350-1, you can set which events are to initiate a hardware interrupt. For this
purpose, parameterize the FM 350-1 interrupts in the parameterization screens.
What is a Hardware Interrupt?
If you want to program a response to a specific event independently of the CPU cycle, each
counter of the FM 350-1 can initiate a hardware interrupt. The CPU interrupts the cyclic
program on receiving the interrupts and executes the hardware interrupt OB.
Which Events Can Initiate a Hardware Interrupt?
Various events can initiate a hardware interrupt during operation of the FM 350-1:
Counter modes
●
Opening of the gate (in the operating modes with hardware or software gate)
● Closing of the gate (in the operating modes with hardware or software gate)
● Overflow
● Underflow
● Zero pass
● Reaching Comparison value 1 or 2 in the up direction
● Reaching Comparison value 1 or 2 in the down direction
● Setting the counter with an external signal
● Latch
Measure Modes
●
Opening of the gate (in the operating modes with hardware or software gate)
● Closing of the gate (in the operating modes with hardware or software gate)
● Measured value outside limits
● End of measurement
You can select any number of events for hardware interrupt initiation. For hardware
interrupts on reaching the comparison value, you must observe the marginal conditions for
the behavior of digital outputs (see the section Behavior of the Digital Outputs (Page 109)).