REDSTONEPEDIA › Circuits › Pulse shapers

Signal shortener (pulse limiter)

at most 2 ticks (0.1 s) · 2 blocks

However long the input stays on, the output pulse lasts at most 2 ticks (0.1 s).

starts after 4 ticks (0.2 s) · needs an input of at least 6 ticks (0.3 s) · made of observer, sticky piston · fits in 1×3×1

24 versions, 2 to 511 ticks

at most 2 ticks (0.1 s)Signal shortener3D view loading (or not available in this browser)

Every size 24

The best design for each size: pick one to see it.

sizeblocksnumbers
2 ticks (0.1 s) (this page)2 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 6 ticks (0.3 s)
4 ticks (0.2 s)8 blocksstarts at once · needs an input of at least 2 ticks (0.1 s)
6 ticks (0.3 s)8 blocksstarts at once · needs an input of at least 2 ticks (0.1 s)
7 ticks (0.35 s)12 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 3 ticks (0.15 s)
8 ticks (0.4 s)8 blocksstarts at once · needs an input of at least 2 ticks (0.1 s)
10 ticks (0.5 s)5 blocksstarts after 1 tick (0.05 s) · needs an input of at least 2 ticks (0.1 s)
12 ticks (0.6 s)9 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
14 ticks (0.7 s)9 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
15 ticks (0.75 s)12 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 3 ticks (0.15 s)
16 ticks (0.8 s)9 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
18 ticks (0.9 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
20 ticks (1 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
22 ticks (1.1 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
23 ticks (1.15 s)12 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 3 ticks (0.15 s)
24 ticks (1.2 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
26 ticks (1.3 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
28 ticks (1.4 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
30 ticks (1.5 s)13 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
31 ticks (1.55 s)12 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 3 ticks (0.15 s)
34 ticks (1.7 s)17 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
36 ticks (1.8 s)17 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
38 ticks (1.9 s)17 blocksstarts after 2 ticks (0.1 s) · needs an input of at least 3 ticks (0.15 s)
127 ticks (6.35 s)12 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 3 ticks (0.15 s)
511 ticks (25.55 s)12 blocksstarts after 4 ticks (0.2 s) · needs an input of at least 3 ticks (0.15 s)

Try it

Hold IN under the view for a long press, tap it for a short one: the box marked OUT turns red while the output is on. Press play under the view to watch a demo on a loop; touch any other control to take over.

How this design does it: The smallest 2-tick pulse limiter, 2 blocks: a sticky piston lifts an observer when the input turns on, and the observer fires once as it lands, into the cell behind it (the output, a 2-tick pulse); pulled back down when the input turns off, it fires under the output, into nothing.

Build it

Download .litematic Download the design as text

The .litematic opens in Litematica (Minecraft 26.3): every block of the design in one region. The text file is the same build written as plain text, block by block.

Blocks used: observer sticky piston

Details: how it works, measurements and properties

In depth

However long the input stays on, the output pulse lasts at most L = 2 ticks (0.1 s); it starts 4 ticks (0.2 s) after the input turns on. (An input shorter than L may come out shorter.) It handles every input pulse of 6 ticks (0.3 s) or longer.

Use it to cut a long signal down to a short, fixed pulse.

How to try it

Press play under the view to watch the demo on a loop (the badge reads demo with the step it is on; the same sequence is drawn as a timing diagram below). Touch any control to stop it and try the circuit yourself.

To try it: press and hold the IN button of the bar (or the cell tagged IN) to power that input; a quick tap sends a short 2-tick pulse.

Inputs are tagged in lime; the output is tagged OUT: the redstone lamp in that cell (the view adds it to show the output) lights while the output is on (the output strip by the demo badge shows its last 40 game ticks, 2 seconds). Drag to look around, pinch or scroll to zoom, step one game tick at a time with the step button.

Inputs and output over time

The input follows this schedule (the 3D view's demo plays the same). Lime: an input is on; orange: the output is on (taller = a stronger signal, 1 to 15). Time runs left to right in game ticks (20 ticks = 1 s).

a 30-tick inputa 40-tick inputINOUTticks020406080100120140160180200220240260280300320340360380400

Swipe the diagram sideways: the whole sequence lasts 425 ticks (21.25 s).

Step by step (11 lines)
in  2 ticks (0.1 s): +4 for 2
in  3 ticks (0.15 s): no output  <- not handled
in  4 ticks (0.2 s): no output  <- not handled
in  5 ticks (0.25 s): +4 for 1  <- not handled
in  6 ticks (0.3 s): +4 for 2
in  8 ticks (0.4 s): +4 for 2
in 10 ticks (0.5 s): +4 for 2
in 15 ticks (0.75 s): +4 for 2
in 20 ticks (1 s): +4 for 2
in 30 ticks (1.5 s): +4 for 2
in 40 ticks (2 s): +4 for 2

Measurements

metricvaluewhat it means
L2 ticks (0.1 s)the length of the output pulse
delay4 ticks (0.2 s)the time from the input's edge to the start of the output pulse
min-pulse6 ticks (0.3 s)the shortest input pulse handled correctly (every longer one works too)
tileableevery 2 (2 0 0)

Notes from its designer

The smallest 2-tick pulse limiter, 2 blocks: a sticky piston lifts an observer when the input turns on, and the observer fires once as it lands, into the cell behind it (the output, a 2-tick pulse); pulled back down when the input turns off, it fires under the output, into nothing. Copies stand side by side every 2 blocks. Detail: inputs of 6 ticks or more.

Properties

StudyPulse shapers
KindSignal shortener (pulse limiter)
Blocks placed2 (not counting the input levers or buttons and the lamp the view adds)
Box1×3×1 (3 blocks of space)
Made of (the blocks that change state)observer, sticky piston
Inputs / outputsIN (repeater) / OUT
The same build is also2-tick pulse · 2 blocks (the same blocks, listed as another kind)
Flagsseveral versions of one mechanism
Design filepulse-limiter-piston-observer-L2

The design file

on GitHub

Design file (15 lines)
# Signal shortener: at most 2 ticks (0.1 s) · 2 blocks
# https://vjeux.github.io/redstonepedia/circuits/pulse/pulse-limiter-piston-observer-L2.html
name: pulse-limiter-piston-observer-L2
circuit: pulse-limiter
tile: 2 0 0
port input: 0 0 1
port output: 0 2 -1
origin: 0 0 0
palette:
  O minecraft:observer[facing=south,powered=false]
  S minecraft:sticky_piston[extended=false,facing=up]
layer 0:
  S
layer 1:
  O