The GUI has two main modes. Depending on which mode the assembler is in, the block will behave in different ways.
The assembler will cycle through the elements in the top slots and deploy the right element at the right time. The assembler can be used in tree farms to cycle through different types of saplings.
In this mode, the Assembler must be wired up with a bundled cable. Each slot corresponds to a different redstone color current, enabling it to choose which object to use by simply toggling the redstone color.
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