Tag: initialization

The perils of FB_init and others

July 24, 2022 · 3 min read
FB_init and the Call After Init pragma may seem like the perfect place to put code that only needs to be run once, but be sure to check the fine print. The information may not be available outside the cyclic PLC context. Here are functions that might not work as expected.

Triggers, falling vs rising and PLC startup yields different behavior

March 4, 2021 · 3 min read
The trigger output behavior of the R_TRIG vs F_TRIG is different on the first PLC cycle. During normal operation they are inversely identical.