Minecraft Wiki:Sandbox/Luotiansha

Transmission components
Transmission components propagate signals and pulses from power components to mechanism components. Complex effects can also be produced by allowing a signal to affect itself or its circuit.

Redstone dust
Redstone dust transmits power.


 * Placement


 * Redstone dust is placed by right-clicking with redstone (redstone is the item, redstone dust is the block). Redstone dust can be attached to the top of any opaque block, or to the top of glowstone, an upside-down slab or upside-down stairs. If the attachment block is removed, the redstone dust drops as an item.


 * When placed, redstone dust configures itself to point toward adjacent redstone dust (at the same level or one level up or down), correctly-facing redstone repeaters and redstone comparators, and power components. If there is only one such neighbor, redstone dust forms a line pointing toward and away from that one neighbor (which can cause it to point toward blocks it wouldn't normally point toward). If there are multiple such neighbors, redstone dust forms either a line, an "L", a "T", or a "+". If there are no such neighbors, redstone dust forms a large directionless dot. Redstone dust does not automatically configure itself to point toward adjacent mechanism components, it must be arranged to do so.


 * When two redstone dust trails are placed vertically diagonally (one block over and one up, or one over and one down), the lower dust trail appears to crawl up the side of the higher block to join the other dust. This linking can be cut by an opaque block above the lower trail, which prevents the two trails from connecting. If the higher trail is on an upside-down slab or upside-down stairs, the higher trail configures itself to point toward the lower trail (and other adjacent dust), but the lower trail (although visually) does not configure itself to point toward the higher trail (including not appearing to crawl up the side of the slab or stairs).


 * The directions in which redstone dust configures itself can affect whether it powers adjacent opaque blocks and mechanisms.


 * Activation


 * Redstone dust can be turned ON by any adjacent power component, redstone repeater pointing at it, or strongly-powered opaque block. Redstone dust can also be turned ON by other adjacent powered redstone dust, but the power decreases with distance from a strongly-powered block. Redstone dust transmits power up to 15 blocks away.


 * Redstone dust can transmit power diagonally upward to dust on an upside-down slab or upside-down stairs, but not diagonally downward from an upside-down slab or upside-down stairs.


 * Effect


 * Powered redstone dust turns ON any mechanism component it is configured to point at. It powers, weakly, an opaque block that it lies on or points to.

Redstone repeater
A redstone repeater is used to transmit power, strengthen redstone dust signals weakened by distance, delay a signal, and redirect a signal.


 * Placement


 * A redstone repeater can be attached to the top of any opaque block, or to the top of an upside-down slab or upside-down stairs. If the attachment block is removed, the redstone repeater drops as an item.


 * A redstone repeater is marked with an arrow pointing toward its front. The repeater reacts only to signals from the block behind it and propagates signals only to the block in front of it (in the direction of the arrow). It also has an adjustable delay that can be set from 1 to 4 ticks by right-clicking it.


 * Activation


 * A redstone repeater is turned ON by any powered component at its back and is unaffected by the powered state of any block beside, above, below, or in front of it (but see below about locking a repeater).


 * Effect


 * A powered redstone repeater turns ON redstone dust or a mechanism component in front of it, or strongly powers an opaque block in front of it. It has no effect on the blocks under, above, beside, or behind it.


 * A redstone repeater not only strengthens it for further transmission, it also delays it by 1 to 4 ticks. A redstone repeater also increases the duration of any pulse shorter than its delay to match the duration of its delay.


 * A redstone repeater can be locked by powering it from the side with another redstone repeater or with a redstone comparator. A locked repeater does not change its output state until unlocked, even if its input changes. A locked repeater displays its locked status with a bedrock bar.

Redstone comparator
A is used to compare or subtract two signals, or to measure how full a container is.


 * Placement


 * A redstone comparator can be attached to the top of any opaque block, or to the top of an upside-down slab or upside-down stairs. If the attachment block is removed, the redstone comparator drops as an item.


 * A redstone comparator is marked with an arrow that point toward its front. The comparator takes a signal from its back as its input, and outputs a signal to the block in front of it, but can also be affected by signals from its sides (see below).


 * A redstone comparator has two modes. Right-clicking it toggles between comparison mode (front torch down/off) and subtraction mode (front torch up/on).


 * Activation


 * A redstone comparator is turned ON by a power source at its input or a power source separated by one opaque block from its input. Power sources include any powered component, a non-empty container, a container minecart on a detector rail, a command block that has run its last command successfully, a cauldron containing water, an end portal frame with an eye of ender, or a jukebox with a record. ) either at its back or separated from its back by an opaque block. It is not affected by blocks beneath it or above it, but its signal strength can be modified by signals from its sides (see below).


 * Effect


 * A powered redstone comparator turns ON redstone dust, a properly-facing redstone comparator or redstone repeater, or a mechanism component in front of it; or strongly powers an opaque block in front of it – all at the same power level as its input signal (unless modified by a side signal, see below). It has no effect on blocks in other adjacent positions (including the block beneath it).


 * The output of a redstone comparator can be affected by a signal provided from its side by a transmission component (redstone dust, redstone repeater, or another redstone comparator only):
 * In comparison mode, a redstone comparator propagates its input signal only if the input signal is greater than the side signal, and outputs no signal if not.
 * In subtraction mode, a redstone comparator outputs a power level equal to the difference of the power level of the input signal minus the power level of the side signal.


 * A redstone comparator that is activated by a container outputs a power level in proportion to how full the container is (rounded up, so a single item in a container produces a power level of at least 1). A container's fullness is measured by stacks: for example, a single shovel (a non-stackable item), 16 signs, or 64 sticks are all considered to be equivalent, full stacks.


 * The Comparator Output Table (right) shows the minimum stacks ("s") plus items ("i") required to produce a specific power level from a container. For example, to get power level 5 from a hopper, put 1 stack plus 28 items in the hopper. Divide items by 4 and round up for items with a stack maximum of 16. The values for the chest, dispenser, furnace and hopper apply to minecarts with those components as well (when on a detector rail).


 * Some blocks (such as crafting tables, enchantment tables, etc.) can hold items temporarily while the player uses the block's interface – the items are returned to the player if the player exits the interface with items still inside. Other blocks (such as beacons) only consume items. Putting items in these blocks never activates a redstone comparator.