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I am trying to make a setup, where I send a recipe to an array of assemblers and as soon as an assembler has accepted a recipe, it should no longer listen for new recipes. I thought I could simply use a decider by reading the set recipe from the assembler, but it does not look like an assembler sends out, what it is producing. then I thought I could simply send the recipe(s) and let a selector send 1 recipe and put a decider in between the selector and the assembler, making the decider into a memory module (looping its signal) and have another selector send the recipe, if the memory decider if it did not already have a recipe. but this also failed because its not possible to send/receive zero signals.
Anyone have a suggestion on how to solve this - once a recipe is set, dont listen for new recipes.

You could configure the assembler to read the ingredients and use that as input for your decider. Might require you to use the other wire to prevent signal contamination and is mutually exclusive with reading the contents. And it obviously won't work with recipes taking no ingredients.

Jmich888 wrote: Mon Apr 27, 2026 1:36 am Anyone have a suggestion on how to solve this - once a recipe is set, dont listen for new recipes.

Why actually do you have this request? What problem are you trying to solve?

In the past I encountered 4 situations that might lead to this request.

Situation 1: multiple machines are being sent the same recipe and at least one of them is also set to "read content" or "read ingredients". This will send the content or ingredient list to every machine, and the machines will interpret this as recipe and switch to unwanted items.

Situation 2: As soon as ingredients are being delivered to the assembling machine(s), there are not enough of them any more in regular stock, so the sender of the recipe decides to not send the recipe any more. The items are being given back, the recipe is eligible for production again, and it's set in the machine again, and the cycle starts again with no item being crafted at all.

Situation 3: while crafting, some item with higher priority is detected to have demand so the sender of the recipe changes to the higher priority recipe prematurely

Situation 4: you want exact amounts in the output, so after one craft the machine must stop and must never start with the next item immediately.


How to resolve:

1: isolate the machines. Select one machine to read content or ingredients. Send the recipe to this machine with one wire, and send the recipe to the other machines with a different wire. If your recipe is the output from some decider, send it to the 1st machine with green wire, and to the other machines with red wire from the decider. Set the 1st machine to read ingredients and connect a red wire to that machine, different from the red wire the other machines are connected. On the red wire from the 1st machine, there are the ingredients and nothing else. You can also read content this way. However, if you want to read content from every machine, you need to isolate every machine from each other.

2 and 3: use a latch to fix the recipe for a given amount of time/ticks

4: read the "working" condition of each machine. If the number equals to the number of machines, you know every machine is actually crafting. Stop sending the recipe signal now. The machines will continue crafting but stop after they finished, since there is no recipe any more.

Thank you for your answer

In the mean time, I found a solution, that does not require to read what the machine is doing. Let me explain...

I want to manage manufacturing remotely, so I can sit in orbit and tell the machines on the planet, what to produce.
1. in orbit I have a constant combinator where I enter all the things I want the machines to produce and how many machines should produce each thing - e.g. I want 3 machines to produce copper cable, so I set a slot in the constant combinator to Copper cables [3].
2. On the planet I have ensured all the Resources available and getting other resources from other planets.
3. I have placed all the machines needed for manufacturing, on the planet and ticked "Get Recipe",
4. each machine is then has a number of circuit units that reads manufacturing requests and here was the reason for my question. I need to check if a machine already have a recipe or not - if it has, then just keep producing that. I fugured out that I could just make a memory module, using a decider combinator to remember if a recipe was already sent to the machine and which recipe. This setup is also sending a signal back saying what it is producing, so I can subtract it from the number of machines wanted for this recipe - e.g. want 3 machines to produce copper cables and this machine has received the recipe, I only want 2 more.

Next I will set up a bunch of Display Plates and Nixie Tubes, in orbit, so I know whats going on down there on the planet.
Later I will set up a number of cargo rockets the same way, using the same method.