Redstone is a way of creating circuitry inside Minecraft that can be used to make many different contraptions and creations.
To get started, you’ll want to get some redstone dust. This is a key element in creating circuits and crafting other redstone components. Ways of obtaining it include:
Mining for redstone ore with an iron pickaxe or better
Finding redstone in structures (i.e. Jungle Temples, Ancient Cities, Woodland Mansions etc.)
Mob drops from witches
Trading cleric villagers
Villager gifts for the Hero of the Village status effect
Redstone has many different components that can be used individually or together to create circuits.
Redstone dust: Redstone dust can be used like a wire and by default a signal can travel through redstone dust up to 15 blocks with a full power source.
Redstone torch: Redstone torches are a power source that can give redstone a signal strength of 15. They can also be turned off with other power sources.
Block of Redstone: Gives off a signal in the direction of all faces of the block. It cannot power the block next to it.
Redstone Repeater: Can be used to extend a signal with a delay. It can also power a block. The default delay is 1 tick but can be extended for up to 4 ticks by right-clicking the repeater.
Note on ticks: Ticks are the way Minecraft keeps time. In a perfect situation, there are 20 ticks in a second.
Redstone Comparator: Comparators have a few different functions.
They can extend a signal. Unlike repeaters, the signal strength that goes into the comparator is the same strength that is output by default.
They can also be used as a type of switch by inputting two signals into the comparator.
Comparators also have subtract mode. To enter this mode, right-click the comparator. In subtract mode, the output signal is the signal being input into the back of the comparator minus the signal input on the side of the comparator.
Comparators can also check how full a container is. If placed next to a container (i.e. chest, hopper, shulkerbox, etc.) the signal strength outputted is determined by how full that container is in comparison to how much it can hold.
Pistons and Sticky Pistons: Pistons are used to move other blocks. The normal piston will push blocks in front of it and then once it retracts it leaves the block(s) where they were pushed with the exception of slime blocks and honey blocks. A sticky piston when retracted will pull the closest block back except for slime and honey blocks which allow groups of blocks to be pulled by the sticky piston and regular piston. Both kinds of pistons have a push limit of 12 meaning they can move up to 12 blocks that are placed in front of it. Any more than that, the piston won’t move. *Note, not all blocks are movable by pistons.
Observers: Observers trigger when the block in front of it changes state. When that happens it puts out a redstone signal pulse of 1 tick. This signal is output on the back of the block. Some block state changes include but are not limited to, breaking/placing blocks, a block moved by a piston in front of the observer, crop growth, etc.
Hoppers: Hoppers are used to move items. They can be locked by powering the hopper with redstone. A locked hopper will accept items, but will not allow those items to leave.
Droppers: Drops one item out of its storage randomly when given a redstone signal pulse.
Dispensers: Dispensers are similar to droppers however, certain items that are usable will be used instead of dropped. (I.e. water buckets will dispense a water block and flow, Arrows will shoot out of the dispenser rather than being dropped, fire charges get fired out of the dispenser rather than dropped etc.)
Lecterns: Lecterns while usable without redstone do output a redstone signal pulse of one tick when the page is turned. It can also be used with a comparator to send a signal with a strength of 1-15 depending on which page you are on.
Target Blocks: Target blocks give off a signal pulse when shot by a projectile (i.e. arrow, trident, etc.) the more accurate the shot is toward the center of the target block, the stronger the signal output is.
Levers: Switches that can activate or deactivate redstone depending on their state.
Lightning Rods: When a lightning rod is struck by lightning it gives off a redstone signal pulse lasting 8 ticks.
Daylight detectors: The daylight detector detects if it’s daytime or nighttime. You can invert whether it is looking for daytime or nighttime by right-clicking the block.
Sculk Sensors: Sculk sensors detect vibrations from nearby and output a redstone signal for 40 ticks when triggered. The signal strength is dependent upon how close the vibration is. Wool can be used to stop detections from certain directions depending on where the wool is placed.
Tripwire Hooks: Tripwire hooks are triggered by an entity touching or crossing through the string between the hooks.
Trapped chests: These chests give off a redstone signal which is constant when opened and only stops once it has been closed.
TNT: Explosive that destroys other nearby blocks and damages entities which can be triggered by redstone.
Redstone Lamps: Redstone lamps are light sources that can be activated with a redstone signal.
Note Blocks: Plays a note when activated with redstone. The instrument a noteblock plays can be changed by changing the block underneath the noteblock and the pitch can be changed by right-clicking the noteblock.
Buttons: Buttons can be pressed to create a signal for a specific number of ticks. Stone-based buttons create a signal for 20 ticks, wooden buttons create a redstone signal for 30 seconds.
Pressure plates: Pressure plates output signals when certain entities are on them. For wooden pressure plates, any entity living entities, items, etc. will activate a signal strength of 15. Stone pressure plates can only be activated by living entities (i.e. players, mobs, etc.) and outputs a signal strength of 15. Weighted pressure plates such as the light weighted pressure plate and heavy weighted pressure plate send out a varying signal strength depending upon how many entities are on top of them.
Common Circuit Mechanics and Uses
There are many common circuits and mechanics used throughout redstone to create machinery. You can utilize one or many of these circuits to make a system of your own using redstone.
Transmission and Powering
Transmission describes how a redstone signal travels. Powering refers to general transmission mechanics
Redstone signals which have full power can transmit a signal through redstone dust up to 15 blocks.
Signals can be extended using a repeater. The repeater adds 1-4 ticks of delay.
You can branch off signals in different directions using both redstone dust and other components.
You can power a block with certain signals and pass the signal through a block. This is often referred to as strong powering or hard powering the block.
Repeaters and certain blocks can be used to allow or prevent a signal from passing through.
Redstone wires can connect and cross each other so be certain you want them to be connected in certain cases.
Blocks and components can be powered. There are two different types or levels of power. These are typically referred to as either hard-powered/strongly powered or soft-powered/weakly powered.
Solid blocks that are given power through a power component directly, through a comparator, or through a repeater are hard-powered. Hard-powered blocks can transmit the signal further to the blocks adjacent to them.
Solid blocks that are given power through a non-power component such as redstone dust are soft-powered. Soft-powered blocks take in a power signal and can transmit that signal to other components but cannot transmit a signal further to the adjacent redstone dust.
Shown in the above image are 3 block power states. Referring to the redstone lamp, the left-most is considered not powered, the middle being soft powered and the right-most being hard powered.
Transparent blocks cannot be powered.
A solid block cannot power another solid block without a redstone component in between.
Powering a hopper locks it making it so that items cannot flow out of the hopper.
Horizontal transmission is how redstone travels in the X and Z directions. It can optionally include the Y direction.
Vertical transmission is how redstone travels upwards in the Y direction. It can optionally include moving in the X and Z directions as well. There are many different ways to approach vertical transmission
(Redstone) Torch Towers: Torch towers are a way of vertical transmission using block powering by alternating blocks and redstone torches. Powering the block at the base of the tower can invert the signal.
Staircases/Redstone Ladders: You can use a staircase-like structure that travels in both vertical and horizontal directions in order to run a redstone signal upwards. There are a few ways to approach this method.
Observer Towers: You can use observers to look for a block state change by placing its observing face downward to transmit a signal upward. Or place the observing face upward to transmit downward.
Observers with Liquids: You can use an observer’s functionality to detect flowing water, lava or bubble columns which can be a way of transmitting the signal
Dropped & Flowing items: You can use a pressure plate (wooden, or weighted) to detect dropped items. You can use a dropper to drop the items. You can also use a hopper and comparator to detect if items have been put into a hopper. You can use the water and bubble columns to move the items both vertically and horizontally.
Logic gates create behaviors similar to programmatical logical operators.
The NOT gate, is used to get the opposite of what a signal is. It’s also commonly called an inverter as it takes the signal and makes it the opposite thus inverting it.
The OR Gate is used when you have at least 2 inputs and you want at least one of many inputs to be powered on. It can be one or many of the inputs and the result will be the same.
XOR gates are similar to OR gates. You must have at least 2 inputs. The difference is that it is the exclusive or meaning that it is one and only one signal is on for the signal to pass through the gate. If multiple signals are on, the output will be off.
The NOR gate is the opposite of the OR gate. When none of the signals are on, the output is on. If one or more of the signals going into the NOR gate is turned on the signal going out of the NOR gate is turned off.
The XNOR gate is the opposite of the XOR gate.
AND gates have at least 2 inputs. All of the inputs must be on in order for the signal going out of the gate to be turned on.
NAND gates are the opposite of AND gates. They have at least 2 inputs. When all of the signals going into the gate are turned on, the output turns off. Otherwise, the output of the gate is on.
IMPLY gates allow a signal to pass through either if both inputs are on or strictly the first input is on. If you labeled the inputs A and B for example, it’d either turn on when both A and B are on or when just A is on. But not when only B is on as A being true implies that B is true but, B cannot imply that A is true.
Pulse circuitry modifies the duration of a pulse. Sometimes specific pulse lengths are necessary for certain kinds of redstone machinery.
Pulse generators: The Pulse generator creates a pulse of a specific duration.
Pulse Limiters: Pulse limiters, also called pulse shorteners shorten the duration of a pulse
Pulse Multipliers: The pulse multiplier outputs many pulses for every pulse that is input.
Pulse Dividers: Pulse dividers, also called pulse counters output a signal after a certain amount of input pulses have activated it.
Clocks are a subset of pulse circuits. It repeats a specific pulse. Clocks in some cases can be turned on or off or run indefinitely.
Repeater clocks are made using repeaters, and redstone dust in a loop.
Comparator clocks are made with comparators and the signals lose strength over time which makes them turn off after a certain time.
Hopper clocks use two or more hoppers moving items between them to create a timed signal.
Piston clocks work by moving a block with a piston to open or close portions of the circuit at certain times causing a loop.
Observer clocks work by constantly making one or more observers see a change to the block in front of them which makes the observer output a signal repetitively.
Item despawn clocks rely on an item or other entity activating another redstone component (i.e. a pressure plate) until it despawns
Minecart clocks use a minecart in either a loop or oscillating motion over a detector rail to generate a repeated signal.