Factorio Forums

When input signals are changing fastly, output from decider combinator GUI can mismatch its input.

How to reproduce: In attached picture, two selector combinators select one random signal from one constant combinator with A=1 B=-1, their ouputs are wired into a decider combinator that only ouputs its inputs when every input is negative. Then pause the game multiple times you will see sometimes the signals mismatch.

This is how combinator works, if you use the /editor to pause the game, you can more precisely control time flow, the game update circuit values at most 60 times per second, every tick, and it takes 1 tick for the value in the input of a combinator to pass through the output. The mismatch you see is most likely that 1 tick delay.

Thanks, it makes sense. I understand how combinator works, didn't realized that input/output signals in GUI reflect current tick state.