Get a time difference in EPICS database

[洪春霞 <hongchunxia@sinap.ac.cn>]

Title: Get a time difference in EPICS database

Hi,
I want to get a time difference in EPICS database, the record of h:Systemtime1 is run when ioc is start, that is, it is the realtime time.
The record of h:Systemtime2 is get when A=3 in the record(calcout,"h:monitor_time"), and it should be executed once, but now I can not get the time of h:Systemtime2.
When I input “camonitor h:Systemtime2” in another Terminal, I always get “h:Systemtime2 <underfined> UDF INVALID”,and I input “camonitor h:time_plus” in another Terminal, I get the time is the value of C.
That is to say, the record of h:Systemtime2 is not executed.

Can you give me some advice? Thank you very much.
Best Wishes.

The database which I use is as follows:

record(ai, "h:status")
{
}
record(stringin,"h:Systemtime1")
{
        field(DESC,"Systemtime1")
        field(DTYP,"Soft Timestamp")
        field(SCAN,"1 second")
        field(PINI,"YES")
        field(INP,"@%s")
}
record(stringin,"h:Systemtime2")
{
        field(DESC,"Systemtime2")
        field(DTYP,"Soft Timestamp")
        field(INP,"@%s")
        field(DISV,"0")#If DISV=DISA, then the record will be disabled
        field(SDIS,"h:monitor_time PP MS")#
}
#This is the value that is compared with DISV to determine if the record is
#disabled. Its value is obtained via SDIS if SDIS is a database or channel access
#link.
record(calcout,"h:time_difference")
{
        field(CALC,"A=B?(C-D):0")
        field(INPA,"h:status PP NMS")
        field(INPB,"3")
        field(INPC,"h:Systemtime1 PP NMS")
        field(INPD,"h:Systemtime2 NPP NMS")
        field(OUT,"h:time_plus PP NMS")
        field(OOPT,"Transition To Non-zero")
}
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hongchunxia