plc5 slc interrupt model

I'm trying to understand the STI
interrupt model for a verification
project. When an STI interrupt
is triggered, are inputs scanned and
outputs updated by default or only
explicitly through immediate instructions ?

Greetings Geoffrey,

no ... the STI will NOT normally cause an I/O update when it runs ... if you need that functionality, then you'll need to add an "immediate update" type instruction to the STI ...

and welcome to the forum ...