[MC-11165] The upward facing piston monostable is both orientational and coordinate dependant > Huge inconsistency Created: 06/Mar/13  Updated: 21/Aug/24

Status: Reopened
Project: Minecraft: Java Edition
Component/s: None
Affects Version/s: Snapshot 13w10a, Snapshot 13w10b, Minecraft 1.5.1, Minecraft 1.5.2, Snapshot 13w18c, Snapshot 13w19a, Minecraft 1.6.1, Minecraft 1.6.2, Minecraft 14w32a, Minecraft 1.9, Minecraft 1.10.2, Minecraft 16w43a, Minecraft 1.12, Minecraft 1.14, 20w07a, 20w08a, 20w18a, 1.16.1, 20w27a, 20w30a, 1.16.2 Pre-release 1, 1.16.2 Release Candidate 1, 1.16.2, 1.16.3 Release Candidate 1, 1.16.3, 1.16.4 Pre-release 2, 1.16.4, 20w46a, 20w51a, 1.17.1, 1.19.1 Release Candidate 2, 1.20.2
Fix Version/s: None

Type: Bug
Reporter: DicoTheRedstoner Assignee: Unassigned
Resolution: Unresolved Votes: 32
Labels: experimental_redstone_fixed

Attachments: File 2019-08-19 04-15-00_2.mp4     File 2024-08-20_23-17-03.mp4     PNG File Picture 1.png     PNG File Picture 2.png     PNG File Picture 3.png     PNG File Picture 4.png     PNG File Picture 5.png     PNG File Picture 6.png     PNG File Picture 7.png     PNG File Picture 8.png    
Issue Links:
Duplicate
is duplicated by MC-11064 New T-Flip Flop nonfunctioning Resolved
is duplicated by MC-12518 directional quirk with redstone Resolved
is duplicated by MC-12552 Directional Bug (Piston) Resolved
is duplicated by MC-15583 Piston Monostables Resolved
is duplicated by MC-24009 Directional issue with Redstone Flip-... Resolved
is duplicated by MC-30506 Piston + strongly powered blocks pick... Resolved
is duplicated by MC-150121 monostable circuit does not power alo... Resolved
is duplicated by MC-159186 Different pistons activate depending ... Resolved
is duplicated by MC-174753 One Tick Pulse Pistons Directionality Resolved
is duplicated by MC-182166 Target block powering of pistons diff... Resolved
is duplicated by MC-192232 Zero-tick piston not gettin powered f... Resolved
is duplicated by MC-196123 T-Flip Flop only working in east/west... Resolved
is duplicated by MC-204875 Piston and Sticky Piston do not recie... Resolved
Relates
relates to MC-182452 Pistons powered by redstone on slabs ... Open
CHK:
Confirmation Status: Confirmed
Category:
Redstone
Mojang Priority: Low
Area: Platform

 Description   

The upward facing piston monostable is very inconsistent.
I will show 4 situations, each with 2 inputs, 2 pistons as outputs, and 2 pictures of what happens when I flick the first or second lever.
Each of this has the lever above and on the left, and the pistons on the right and on the bottom. I will change the direction the pistons are facing, and move the setup for each situation.

In situation 1 (Picture 1 and 2), we see that powering the lever on top powers only the piston on the right, and powering the other lever powers the other piston.

In situation 2 (Picture 3 and 4), we see that powering the lever on top powers none of the 2 pistons, and powering the other lever powers the piston on the right.

situation 3 (Picture 5 and 6) is identical to situation 2, the 2 pistons are just facing a different direction, and are in a different location.

situation 4 (Picture 7 and 8) is identical to situation 1, one of the pistons is just facing a different direction, and are in a different location.

The top of the pictures is always facing f:2(North)
Also: I know this is a duplicate, but I just wanted to make the bug more clear

I really hate this bug, and I think it should be fixed by pre-release.

UPDATE:
Powering the monostable with redstone or repeater actually makes a difference.

EDIT: Since 14w19a, this monostable works consistently in one orientation, in the other however it is still coordinate dependant.

Nice 20w18a repro: https://www.youtube.com/watch?v=ptK-7n--yYM



 Comments   
Comment by [Mod] Jiingy [ 21/Aug/24 ]

This issue is fixed in the 24w33a redstone experiment:
2024-08-20_23-17-03.mp4

Comment by [Mod] ampolive [ 09/Jul/21 ]

Can confirm in 1.17.1.

Comment by pulpetti [ 07/Aug/20 ]

In 1.16.2 RC-1

Comment by [Mod] markderickson [ 02/Jul/20 ]

Hi there!

Can confirm in 20w27a.

Comment by [Mod] markderickson [ 27/Jun/20 ]

Still present in 1.16.1.

Comment by 闫懋杰 [ 23/Feb/20 ]

confirmed still in 20w08a

Comment by [Mod] NeunEinser [ 23/Jul/17 ]

Can confirm for 1.12

Comment by [Mojang] Panda [ 30/Oct/16 ]

I can confirm 16w43a.

Comment by [Mod] Michael Wobst [ 29/Oct/16 ]

Is this still an issue in the most recent versions (currently that is 1.10.2, or 16w43a) of Minecraft? If so, please update the affected versions and help us keeping this ticket updated from time to time. If you are the owner/reporter of this ticket, you can modify the affected version(s) yourself.

Comment by [Mojang] Panda [ 26/May/16 ]

torabi dicotheredstoner I can confirm that it is caused by the update order.
Currently: west east down up north south

Depending on if the piston in front or the one below get updated first the circuit behaves different.
It's impossible to avoid all directional behaviour because the updates need some order, but the y-axis shouldn't be updated in between the two other axis.
Because that causes everything that depends on something updating a y-direction before a horizontal one or the other way around, to be directional.

The question is: What order would be best?
Y-Last: west east north south down up
Y-First: down up west east north south
Y-Split: down west east north south up

I think it would make sense to keep the horizontal directions in the same order they have been before to minimize the things that would break. I also don't see any advantage changing it.
Of course you could also switch the places of up and down in all of these.

No matter how you change it, it would break some things that depend on update orders. They would be fixable though.

I made a mod that allows to set the update order with a command (E.g. /updateorder west east north south down up).
If you want to try how different update orders would behave you can download it here: http://www.mediafire.com/download/b9mjwuimu2ei7wg/1.9_UpdateOrder.zip
Video about it with a more general/theoretical approach: https://www.youtube.com/watch?v=aRr3NpmQiCg

Comment by DicoTheRedstoner [ 20/Mar/16 ]

Sorry, yes this is still a concern in the current version, however it has become slightly more stable.
I'm quite certain that it works reliably if the monostable is powered from 2 of 4 directions now, but it's definitely still in the game.

The preferred solution for me would be to make it not power any pistons, but still power repeaters.
Let me argue why:

Nearly every redstone contraption is made to not rely on unreliable bugs in the game, to ensure that it is not coordinate dependant, random, or direction dependant.
So nearly every redstone contraption is made to not use this monostable to power pistons directly, but this monostable is the most often used monostable in the game, so it is important that it will power repeaters. Fixing it this way will break next to no contraptions. Remember that most redstone creations take hours to complete, and some even months. Having to go back and fix them, which might sometimes be impossible, will take another large amount of time.

I know that this way of fixing it doesn't make much sense, but now you know why I prefer it, and I'm sure you can see my point.

Comment by user-f2760 (Inactive) [ 18/Mar/16 ]

No response for over a year.

Comment by Galaxy_2Alex [ 25/Oct/14 ]

Is this still a concern in the current Minecraft version 1.8.1 Prerelease 3 / Launcher version 1.5.3 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by [Mod] Torabi [ 07/Aug/14 ]

According to a comment on this video, this is caused by the order of the block updates:

This is a bug that has existed since pistons were added. To fix the t-flip-flop functionality after the mono-stable circuit add another 1 tick repeater, this is a side affect of the north-south quirk that has existed since like ever, essentially the series of event that the game goes through to propagate redstone is locked, when a block is powered it updated the block above first, then north and then south, then the block below then east and then west. so what's happening because of this is that the block is powering the piston before it powers the side that has the t-flip-flop piston, and by the time that happens, in the games mind, the block is already been moved and no longer is capable of updating the piston, the block is still physically providing power to the piston, however the piston isn't updated until the block is already moved, repeaters however can still pull the redstone current.

Comment by DicoTheRedstoner [ 12/May/14 ]

This is now consistent in one orientation, in the other orientation it is still coordinate dependant.
(14w19a)

Comment by Eric R [ 09/Sep/13 ]

Can confirm for 1.6.2.

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