6. Function blocks6.2 Interrupt function blocksIf there are multiple interrupt requests present sim-ultaneously, the first detected interrupt program will beexecuted, after which the remaining ones will be executedbased on the corresponding order.While the interrupt program is being processed, any otherincoming interrupts at the function block inputs of the sameinstance will not be detected.6.2.1.2 Operating principleA reference value is set at function block input SV. Depending on the operating mode,the function block will be assigned one or two of device inputs I1 through I8 in the cor-responding parameters (at least one of them will be set as a counter input in the para-meters). If the counter input reaches the reference value, the interrupt will be triggered.The system will switch from the main program to the interrupt program and the latterwill be processed.Interaction between main program and interrupt programThe states of function block inputs IC_I1 through IC_04 are passed to the interrupt pro-gram, where they can be processed further as I01 through I04.Function block outputs IC_Q1 through IC_Q4 can be set from the interrupt program. Thecorresponding interrupt program outputs are Q01 through Q04.Main program Interrupt programFigure 187: Input and output states being passed between the main program and interrupt program406 easyE4 11/18 MN050009 EN www.eaton.com
