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I did a search and had a good read, but couldn't see anyone else having reported this issue - so not sure if it's just me. If so, apologies in advance!

The simplest form of the issue is this: an isolated network of items (piercing rounds, in this case) has a decider combinator connected with both input and output. When I hover over the connected power pole I can see that the count of piercing rounds is present (lets say 200). I set the decider to the condition "piercing rounds > 10", and the output as a signal A set to "Input count". My assumption is that this should output A at a count of 200 (matching the input) - is this correct? I have the output connected back to the same network, but I see no A signals of any kind.

Then, I change the output from "Input count" to 1, and I now see "A=1" appear on the network - woohoo! When I change this back to "Input count", it stays latched at 1 (instead of changing to A=200 as I would expect). Then, I switch the A signal to B, and the A signal disappears but B does not appear. If I switch output to 1 then I see B=1; if I switch back to "Input count" I see B=1 still (latched, like before); if I change the signal, they disappear again.

My findings are this: either (1) I'm a muppet and have something weird set up, but I'm finding this at other places in the network too; or (2) there is a bug in the decider combinator that causes the "Input count" setting not to work, by either latching the previous value when the output type is changed, or by clearing everything when the signal is changed.

Hopefully this all makes sense! Screenshot enclosed of the decider combinators settings, and showing how it is latched to the output of 1, not outputting the input count as it is set.

Post the save please.

Decider combinators act as filters and can't map signals.
Set to input count they pass the output signal from input.
Set to =1 they generate the output signal regardless if it exists on input.

If you want to map signals you have to use an arithmetic combinator.

Hey Optera,

Thanks for the response - yes I understand what you are saying, I had misunderstood how the deciders work vs the arithmetic combinators.

For anyone else finding and reading this who appears to be having the same problem, it goes like this:

Arithmetic Combinators will taken an input of some kind, apply a transformation calculation, and output that number on whatever other signal you want (including the same one, if you desire). So you can use this to map one input signal (say, A=10) to a different output signal (e.g. B=10) by multiplying it by 1 (which does nothing), and changing the output signal.

Decider Combinators will evaluate a decision of some kind (e.g. A>5) and then output a signal of your choosing as a 1, or using the Input Count. This is where I misunderstood: if you set the output to use the Input Count setting, then it will output the input count of that exact signal, NOT the one you were evaluating the decision on.

Let's say I had the output of the first Arithmetic Combinator (B=10) hooked up to the input of the Decider Combinator, with the condition of "B > 5", and an output of "C = Input Count". I was expecting that because B=10 (and is therefore greater than 5), that C would be output with the count of B - but this is wrong. What actually happens is, C gets output with the input count of C, which in this case is 0, thus nothing happens. If I was to switch the output to "A = Input Count", then I would be getting A=10 on the decider output, provided the input was connected to the same input source as the arithmetic combinator.

Hopefully that clarifies things for anyone. Thanks to you guys for helping me out!

Thank you so much for this last comment - very useful to discover even in 2022, haha!
I needed an arithmetic combinator to convert a Copper Plate stack count into a Signal count
This worked well!