interrupt read data in int32Driver example

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Dear community,

I would like to learn about the usage of epics interrupt. I found an example routine called `int32Driver` (asyn/iocBoot/ioctestEpics/st.cmd and asyn/testEpicsApp/src). In the `st.cmd` script, there is a record instance that I want to use to run an interrupt because it has `SCAN=I/O Intr`. Here is the example record instance:

record(ai,"asyndevAiInt32A0") {
    field(SCAN,"I/O Intr")
    field(DTYP,"asynInt32")
    field(INP,"@asyn( int32 , 0 , 1.0) ")
    field(LINR,"LINEAR")
    field(EGUF,"100.0")
    field(EGUL,"-100.0")
    field(PREC,"3")
}

After running `epics` using the above command, I tried to read the data generated by the interrupt using `caget asyndevAiInt32A0`. However, the return value of `caget` did not change. How can I make `asyndevAiInt32A0` generate a read data interrupt to software simulate a hardware interrupt that produces new data?