Minecraft Wiki:Sandbox/Luotiansha

Power components
Power components create redstone signals, either permanently or in response to player, mob, and environmental activity.

Block of redstone
A provides constant power. It can be moved by pistons.


 * Activation


 * A block of redstone is always ON.


 * Effect


 * A block of redstone powers adjacent mechanism components (including those above or below) and adjacent redstone dust. It also powers adjacent redstone comparators or redstone repeaters facing away from it.


 * A block of redstone does not power adjacent opaque blocks.

Button
A is used to generate a pulse. A button may be of two types: wooden or stone.


 * Placement


 * A button can be attached to any part of most opaque blocks. If the attachment block is removed, the button drops into the item form.


 * Activation


 * A player can activate a button by right-clicking it. A stone button stays ON for 10 ticks (1 second), while a wooden button stays ON for 15 ticks (1.5 seconds). A wooden button can also be turned ON by an arrow that has been shot at it. In such a case, the button remains ON until the arrow despawns (after one minute) or is taken.


 * Effect


 * While activated, a button and its attachment block both power adjacent redstone dust (including beneath the button, and beneath and on top of the block), and all adjacent redstone comparators or redstone repeaters facing away from it. They also activate all adjacent mechanism components (including those above or below).

Daylight sensor/detector
A can be used to detect the time of the Minecraft day.


 * Activation


 * A daylight sensor, if exposed to the sky ("sl" greater than 0), remains activated while the sun is in in the sky. A daylight sensor blocked from the sky ("sl" equals 0) remains activated while the moon is in the sky.


 * Effect


 * While activated, a daylight sensor powers adjacent redstone dust (including beneath it), and all adjacent redstone comparators or redstone repeaters facing away from it, at a power level proportionate to the height of the sun or moon in the sky. It also activates all adjacent mechanism components (including those above or below).


 * A daylight sensor does not power adjacent opaque blocks.

Detector rail
A is used to detect the passage of a minecart.


 * Placement


 * A detector rail 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 detector rail drops as an item.


 * When placed, a detector rail lines up with adjacent rails, powered rails, and other detector rails, as well as adjacent rails one block above it. If there are two adjacent rails not on opposite sides, or three or more adjacent rails, the detector rail lines up in the east-west direction. If there are no adjacent rails, the detector rail lines up in the north-south direction. If there is an adjacent rail one block above, the detector rail slants to match it (when there is more than one adjacent rail to slant toward, the order of preference is: west, east, south, and north). Other configurations can be created by placing and removing various rail.


 * Activation


 * A detector rail turns ON when a minecart passes over it, and turns OFF when it leaves.


 * Effect


 * While activated, a detector rail and its attachment block (unless attached to a slab or stairs) both power adjacent redstone dust (including beneath the block), and all adjacent redstone comparators or redstone repeaters facing away. They also activate all adjacent mechanism components (including those above or below).

Jukebox (Bedrock Edition)
A with a music disc playing emits a redstone signal of strength 15.

Lectern
A is a block that can hold written books so they can be read.


 * Placement


 * Lecterns can face north, south, east or west, facing toward the player when placed. This has a redstone effect judging on the book page.


 * Activation


 * When the book is turned, the lectern emits a redstone pulse that is one game tick long (0.5 redstone ticks).

Lever
A is used to switch circuits on or off, or to permanently power a block.


 * Placement


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


 * Activation


 * A player can turn a lever ON or OFF by right-clicking it.


 * Effect


 * While activated, a lever and its attachment block (unless attached to a slab or stairs) both power adjacent redstone dust (including beneath the lever, or beneath or on top of the block), and all adjacent mechanism components (including those above or below it). They also activate all adjacent redstone comparators or redstone repeaters facing away.

Lightning rod
A emits a redstone signal strength of 15 when struck by lightning.

Observer
An can be used to detect block changes.


 * Placement


 * An observer can be placed anywhere and can face in any direction, including up or down. When placed, the observer's side that detects block changes (its face) faces away from the player and the side that produces a pulse faces the player.


 * Activation


 * An observer turns ON when the block in front of its face changes state (for example, a block being placed or mined, water changing to ice, a repeater having its delay changed by a player, etc.). The observer stays ON for 2 redstone ticks (4 game ticks, or 0.2 seconds barring lag) and then turns OFF automatically.


 * An observer also turns ON for 1 game ticks after it is moved by a piston.


 * Effect


 * When activated, an observer produces a 1tick pulse from the side opposite its face.

Pressure plate
A pressure plate can be used to detect mobs, items, and other entities. A pressure plate may be of two types: wooden or stone.


 * Placement


 * A pressure plate can be attached to the top of any opaque block, or to the top of a fence, nether brick fence, an upside-down slab or upside-down stairs. If the attachment block is removed, the pressure plate drops as an item.


 * Activation


 * A pressure plate turns ON when an entity (mob, item, etc.) crosses or falls on it, and turns OFF when the entity leaves or is removed. A wooden pressure plate may be turned ON also by falling items and arrow shots. A wooden pressure plate that is activated in this way turns OFF when the object is picked up or despawns (after one minute for a shot arrow, or up to five minutes for an item).


 * Effect


 * While activated, a pressure plate and its attachment block (unless attached to a fence, nether brick fence, slab, or stairs) both power adjacent redstone dust (including beneath the block), and all adjacent mechanism components (including those above or below). They also activate all adjacent redstone comparators or redstone repeaters facing away.


 * Considerations


 * A pressure plate is not solid (it cannot be used as a wall or platform). Usually a block under a pressure plate provides solid ground (for mobs to walk across, items to fall on, etc.), but when a pressure plate is placed on a block with a small collision mask, like a fence or nether brick fence, it is possible for entities to move through the pressure plate and still activate it. Thus, a pressure plate on a fence can be used to detect entities without stopping them (more compactly than a tripwire circuit).

Redstone torch
A powers circuits (horizontally and vertically), and can invert signals.


 * Placement


 * A redstone torch can be attached to any surface (except the bottom) of any opaque block, or to the top of: a cobblestone wall, a fence, glass, nether brick fence, an upside-down slab or upside-down stairs. If the attachment block is removed, the redstone torch drops as an item.


 * Activation


 * A redstone torch turns OFF when its attachment block receives power from another source and turns back on when the block loses power.


 * Effect


 * While activated, a redstone torch and any opaque block above it both power adjacent redstone dust (including beneath the redstone torch, or on top of the block), and all adjacent mechanism components (including those above or below it). They also activate all adjacent redstone comparators or redstone repeaters facing away from it.


 * A redstone torch does not affect the block it is attached to (even if it is a mechanism component).


 * Considerations


 * A redstone torch can burn out (stop turning on) when it is forced to flicker on and off too quickly (by powering and de-powering its attachment block). After burning out, a redstone torch re-lights when it receives a redstone update, or randomly after a short time.


 * One way to cause a burnout is with a short-circuit – using a torch to turn itself off, which then allows the torch to turn back on, etc. For example, placing redstone dust on top of a block with a redstone torch on its side, then putting another block above the torch, causes the torch to power the top block, which activates the dust, which powers the first block, turning the torch off – this feedback loop causes the redstone torch to flicker and burn out. When putting a torch underneath a block, make sure that the block isn't adjacent to redstone dust or the torch can burn out.

Sculk sensor
A sculk sensor emits a redstone signal when it detects a vibration

Target
A emits a redstone signal when hit by a projectile (including arrows, tridents, eggs, snowballs, splash potions, fire charges fired from dispensers, and lingering potions, but excluding ender pearls and eyes of ender).


 * Activation


 * Arrows and Tridents emit a pulse of 10 redstone ticks, while other projectiles emit a pulse of 4 redstone ticks. The closer the projectile is to the center of the block, the stronger the signal it produces is, from 1 (at the edge) to 15 (in the center).


 * Effect

...

Trapped chest
A trapped chest can be used to detect when a player tries to take from it.


 * Activation


 * A trapped chest is turned ON when a player accesses its contents.


 * Effect


 * While activated, a trapped chest and any opaque block beneath it both power adjacent redstone dust (including beneath the block), and all adjacent mechanism components (including those above or below it). They also activate all adjacent redstone comparators or redstone repeaters facing away from it, at a power level equal to the number of players simultaneously accessing its contents (maximum 15).

Tripwire hook
A tripwire hook is used to detect mobs, items, and other entities over a large area.


 * Placement


 * A tripwire hook can be attached to the side of most opaque blocks. If the attachment block is removed, the tripwire hook drops as an item.


 * In order to function correctly, a tripwire hook must be part of a tripwire circuit: two opaque blocks attached to tripwire hooks, at the ends of a tripwire line (one or more blocks of tripwire).


 * To place tripwire, right-click on an adjacent block with a string. Tripwire can be placed on the ground or in the air, and forms a valid tripwire line only if all the tripwire is of the same type. Tripwire is considered on the ground if placed on any opaque block, or on a block of redstone, a hopper, an upside-down slab, or an upside-down stairs. Tripwire is considered in the air if placed on or above any other block. Tripwire on the ground has a short hitbox (1/8 block tall), while tripwire in the air has a taller hitbox (1/2 block tall).


 * If the attachment block under ground tripwire is removed, the tripwire drops as string.


 * A tripwire circuit is properly placed when the tripwire hooks are fully extended and the tripwire line runs continuously between the tripwire hooks. Tripwire lines from separate tripwire circuits can be placed next to each other (in parallel), above each other, and can even intersect each other.


 * Activation


 * A tripwire hook turns ON when an entity (mob, item, etc.) crosses or falls on the hook's tripwire line (but not the tripwire hook), and turns OFF when all entities leave or are removed from the tripwire line. A tripwire hook also turns ON for 5 ticks (1/2 second) when any of its tripwires are destroyed, except when using shears to cut the tripwire. Breaking the tripwire hook, or its attachment block, does not generate a pulse.


 * Effect


 * While activated, a tripwire hook and its attachment block both power any adjacent redstone dust (including below the tripwire hook, or beneath or above the block), and all adjacent mechanism components (including those above or below it). They also activate all adjacent redstone comparators or redstone repeaters facing away from it.
 * Tripwire itself provides no power.

Weighted pressure plate
A weighted pressure plate can be used to detect the number of entities on top of it. A weighted pressure plate may be of two types: light (gold) or heavy (iron).


 * Placement


 * A weighted pressure plate can be attached to the top of any opaque block, or the top of a fence, nether brick fence, an upside-down slab or upside-down stairs. If the attachment block is removed, the weighted pressure plate drops as an item.


 * Activation


 * A weighted pressure plate remains ON as long as there is at least one entity on top of it.


 * Effect


 * While activated, a weighted pressure plate and its attachment block (unless attached to a fence, nether brick fence, slab, or stairs) both power adjacent redstone dust (including beneath the block), and all adjacent mechanism components (including those above or below it). They also activate all adjacent redstone comparators or redstone repeaters facing away from it, at a power level proportional to the number of entities on the weighted pressure plate.