Selectable Timed Interrupt (STI)

[Fred Lee 0]

I use RSLogix MicroStarter Lite to communicate with RSLogix Emulate 500 via RS Linx Classic.  The processor selected is MicroLogix 1000.  I test STI(see attached file).  It seems the STI subroutine is not running( O:0.0/15 is not ON even the Input is ON).

STI Enable bit is toggling(cannot captured using Printscreen because it is toggling too fast) but STI executing is permanent 0.

Anybody knows why?

[Ken Roach 194]

Many of the hardware-related features like discrete interrupts don't work in the Emulator;  the Knowledgebase goes into some depth:

https://rockwellautomation.custhelp.com/app/answers/detail/a_id/55723

But the STI is supposed to work with the Emulator.

I don't understand why you are enabling and disabling the STI in the same File 2.   It's a timed function, and is going to be disabled except between the last rung and the start of the next program scan.   When did you expect it to execute ?

[Fred Lee 0]

Hi Ken Roach! Thanks for your reply. I use STE/STD because I do not want the STI to execute subroutine when the controller is scanning certain rung.  Anyway I have simplified the logics at Main program by removing STD(see attached).  Now the STI is permanently Enabled.  However the result is the same.  And I realized now the bit toggle at STI subroutine file is not working.  Now I use Force On at input at STI subroutine file.  However the Bit Toggle is still working at Main file.

Any idea what is wrong?

[Ken Roach 194]

I cannot understand what you are trying to do;  you're forcing Inputs and Outputs off as well as fussing with the STI, and you're doing it all in the Emulator instead of using real I/O.

 

What is your purpose with this logic ?