Flow Control

Flow Control is a wiring-based mechanic that lets machines selectively allow, block, or route the flow of items or fluids based on electrical signals. Devices that use Flow Control respond to the state and type of the Wire signal to determine whether to pass throughput, block it, or redirect it. Flow Control appears in pipe and belt devices such as Pipe Gate and Belt Filter, and is commonly used together with sensors like Belt Reader to make decisions based on the contents of a stream.

The Pipe Gate limits fluid throughput depending on the Wire input signal. The gate blocks fluids when the signal is Null, Conflict, an integer equal to 0, or a Shape signal. The gate allows fluid throughput when the signal is an integer not equal to 0. When the signal is a Color signal the gate allows fluid throughput only if the fluid matches the input color signal.

The Belt Filter routes the flow of shapes and has two outputs: straight-through (✔) and side output (✘). Which output receives shapes depends on the Wire input signal. The filter blocks the belt (shapes do not move) when the signal is Null or Conflict. When the signal is an integer equal to 0 the filter sends all shapes to the side output (✘). When the signal is an integer not equal to 0 the filter sends all shapes straight through (✔). When the signal is a Shape signal the filter sends matching shapes straight through (✔) and non-matching shapes to the side output (✘). When the signal is a Color signal the filter sends all shapes to the side output (✘).

The Belt Reader is used to inspect flowing shapes and to feed Flow Control logic. The Belt Reader displays the rate of shapes per minute moving through it and outputs the Shape Signal of the shapes on its Wire output. That Shape Signal can be fed into Belt Filters or other wired logic to implement selective routing based on the item shape.

• Use integer signals to implement simple allow/block behavior: 0 to block or divert, any nonzero integer to allow straight throughput.
• Use Shape signals from Belt Reader when you need to route or split specific shapes; pair Belt Reader with Belt Filter to direct matching shapes one way and others a different way.
• Use Color signals with Pipe Gate to allow only fluids of a matching color; Color signals behave differently on belt filters (they cause all shapes to go to the side output).
• Null or Conflict signals are treated as blocking on both pipe and belt Flow Control devices; design circuits to avoid unintended Null/Conflict states.
• Combine multiple Flow Control devices and wiring logic to build conditional sorting, selective fluid routing, and throughput control based on production state.