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Pulse circuit

Edge detector (observer)

Notice changes instead of sustained levels.

6 × 1 footprint1 layer6 blocksTested in 4 rotationsJava Edition 26.2
Open in the simulatorBuild it in the game

Layout

Layer 0 (on the floor)
lever [face=floor, facing=north, powered=false] at x 0, z 0redstone dust at x 1, z 0redstone lamp at x 2, z 0observer [facing=west] at x 3, z 0redstone dust at x 4, z 0redstone lamp at x 5, z 0
redstone dustinputlampobserverarrows point where a device sends its output; north is up

How it works

An observer watching a lamp fires a 2 tick pulse whenever the lamp changes, on and off alike.

  1. The observer watches a block state, and a change schedules a brief output pulse.
  2. Both the watched lamp turning on and turning off can trigger it. The lamp’s off delay shifts the second event.

Timing

Measured at the output: a pulse of 2 game ticks (0.10 s) per event.

Inputs and outputs

  • Inputlever (x 0, y 0, z 0)
  • Outputraw 2 game tick pulse (x 4, y 0, z 0)
  • Indicatordicator: lamp adds 4 game ticks before going dark (x 5, y 0, z 0)

Blocks you need

2 × redstone dust, 2 × redstone lamp, 1 × lever, 1 × observer.

Build it in the game: 6 commands

Relative to where you stand, with x running east and z running south. Paste one line at a time into chat, or into a chain of command blocks. The block art is the game's own; the layout is what the page above shows.

setblock ~0 ~0 ~0 minecraft:lever[face=floor,facing=north,powered=false]
setblock ~1 ~0 ~0 minecraft:redstone_wire
setblock ~2 ~0 ~0 minecraft:redstone_lamp
setblock ~3 ~0 ~0 minecraft:observer[facing=west]
setblock ~4 ~0 ~0 minecraft:redstone_wire
setblock ~5 ~0 ~0 minecraft:redstone_lamp