6. Function blocks
6.2 Interrupt function blocks
 Device inputs
 I01 I02 I03 I04 I05 I06 I07 I08
IT01…IT08
Automatically assigns the user interrupts 1 to 8 that are still available (only for
instances of I01 – I08 that are not in use by other function blocks)
The time between the moment the triggering signal is detected and the moment there
is a response at an output is < 1 ms. If multiple interrupts are executed sim-
ultaneously, the times add up.
Measuring the interrupt load
The runtime for each interrupt source is measured in µs. All measured times are
added over a period of 100 ms. After each 100 ms, the total of all times is evaluated
and the time measurement is cleared. If the interrupts used up more than 50% of the
computing time, the application will be stopped.
The <System_CPU_overload> diagnostic message will be generated and ID19 will be
set to 1.
For more information on how diagnostic messages can be called and processed,
please refer to
Available fixes for high interrupt loads
If the interrupt load becomes too heavy, the following steps can be taken to reduce it:
l
Reduce the number of function blocks
l
Keep the interrupt routine as short as possible
l
Reduce frequencies when using counters
Example of a pulse counter with external direction control in easySoft 8
Device input I1: Counter input C_
Device input I5: Counting direction D_
If the setpoint of <1750> is reached at device input I1, the system will jump to the
interrupt program. Inside the interrupt program, QP04 will be used to set device out-
put Q4 to 1 directly. Q01 will be used to set function block output Q1 to 1. The system
will then jump back to the main program.
Fig. 257: easySoft 8 Main program Pulse counter with external direction
easyE402/24 MN050009ENEaton.com
569
To Next Page
Loading...
Need help?
General