REDSTONEPEDIA › Circuits › Pulse shapers
One pulse when switched off (falling-edge detector)
14-tick pulse · 16 blocks
When the input turns off, the output gives one short pulse of 14 ticks (0.7 s); turning the input on does nothing.
starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) · fits in 4×2×4
Every size 23
The best design for each size: pick one to see it.
| size | blocks | numbers |
|---|---|---|
| 1 tick (0.05 s) | 4 blocks | starts after 2 ticks (0.1 s) · needs an input of at least 2 ticks (0.1 s) |
| 2 ticks (0.1 s) | 2 blocks | starts after 4 ticks (0.2 s) · needs an input of at least 6 ticks (0.3 s) |
| 4 ticks (0.2 s) | 4 blocks | starts after 8 ticks (0.4 s) · needs an input of at least 6 ticks (0.3 s) |
| 6 ticks (0.3 s) | 4 blocks | starts after 10 ticks (0.5 s) · needs an input of at least 6 ticks (0.3 s) |
| 8 ticks (0.4 s) | 4 blocks | starts after 12 ticks (0.6 s) · needs an input of at least 6 ticks (0.3 s) |
| 10 ticks (0.5 s) | 5 blocks | starts after 1 tick (0.05 s) · needs an input of at least 2 ticks (0.1 s) |
| 12 ticks (0.6 s) | 16 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 14 ticks (0.7 s) (this page) | 16 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 16 ticks (0.8 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 18 ticks (0.9 s) | 16 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 20 ticks (1 s) | 20 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 22 ticks (1.1 s) | 20 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 24 ticks (1.2 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 26 ticks (1.3 s) | 20 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 28 ticks (1.4 s) | 20 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 30 ticks (1.5 s) | 20 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 32 ticks (1.6 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 36 ticks (1.8 s) | 24 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 38 ticks (1.9 s) | 24 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 40 ticks (2 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 64 ticks (3.2 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 128 ticks (6.4 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 s) |
| 256 ticks (12.8 s) | 13 blocks | starts after 6 ticks (0.3 s) · needs an input of at least 6 ticks (0.3 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: One fixed-length pulse every time the input turns OFF, however long it was on.
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: comparator copper bulb observer redstone wire repeater sticky piston stone
Details: how it works, measurements and properties
In depth
When the input turns off, the output gives one short pulse of L = 14 ticks (0.7 s), starting 6 ticks (0.3 s) after the input turned off. When the input turns on, nothing happens. It handles every input pulse of 6 ticks (0.3 s) or longer.
Use it to react to something stopping, e.g. a lever being switched back.
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 orange glass marker next to it glows 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).
Swipe the diagram sideways: the whole sequence lasts 913 ticks (45.65 s).
Step by step (13 lines)
in 2 ticks (0.1 s): no output <- not handled in 3 ticks (0.15 s): +9 for 14 in 4 ticks (0.2 s): no output <- not handled in 5 ticks (0.25 s): no output <- not handled in 6 ticks (0.3 s): +12 for 14 in 8 ticks (0.4 s): +14 for 14 in 10 ticks (0.5 s): +16 for 14 in 15 ticks (0.75 s): +21 for 14 in 20 ticks (1 s): +26 for 14 in 30 ticks (1.5 s): +36 for 14 in 40 ticks (2 s): +46 for 14 in 60 ticks (3 s): +66 for 14 in 80 ticks (4 s): +86 for 14
Measurements
| metric | value | what it means |
|---|---|---|
| L | 14 ticks (0.7 s) | the length of the output pulse |
| delay | 6 ticks (0.3 s) | the time from the input's edge to the start of the output pulse |
| min-pulse | 6 ticks (0.3 s) | the shortest input pulse handled correctly (every longer one works too) |
Notes from its designer
One fixed-length pulse every time the input turns OFF, however long it was on.
Properties
| Study | Pulse shapers |
|---|---|
| Kind | One pulse when switched off (falling-edge detector) |
| Blocks placed | 16 (not counting the input levers or buttons the view adds) |
| Box | 4×2×4 (32 blocks of space) |
| Made of (the blocks that change state) | comparator, copper bulb, observer, redstone wire, repeater, sticky piston |
| Inputs / outputs | IN (repeater) / OUT |
| Design file | pulse-oneshot-fall-falling-edge-L14-v32-16b |
The design file
Design file (26 lines)
# One pulse when switched off: 14-tick pulse · 16 blocks # https://vjeux.github.io/redstonepedia/circuits/pulse/pulse-oneshot-fall-falling-edge-L14-v32-16b.html name: pulse-oneshot-fall-falling-edge-L14-v32-16b circuit: falling-edge port input: -1 1 0 port output: 2 1 1 origin: 0 0 0 palette: A minecraft:repeater[delay=4,facing=north,locked=false,powered=false] C minecraft:comparator[facing=west,mode=compare,powered=false] O minecraft:observer[facing=north,powered=false] R minecraft:redstone_wire S minecraft:sticky_piston[extended=false,facing=east] W minecraft:waxed_copper_bulb[lit=false,powered=false] r minecraft:repeater[delay=2,facing=south,locked=false,powered=false] s minecraft:stone layer 0: . ..ss .O.s ..sW layer 1: SO .WCR .r.A .sRR