Verification builds:
1.2.5.15 Beta
Summary:
Prior to 1.2 observers detecting a piston head that it was powering would form a "clock". This was incorrect behavior since observers, normally taking 1 tick to detect and output a signal, would have had it's signal ignored (as the piston head would have been retracting while receiving the pulse, therefore ignoring it). This was fixed in 1.2, perhaps as a side product of the faster observers and the instant chaining observers. It has returned in 1.2.5.15, possibly as a side effect of this bug being fixed:
bugs.mojang.com/browse/MCPE-23947
Steps to Reproduce:
1. Build setup as posted in the attached videos.
2. Turn the lever on to "prime" the setup.
3. Turn the lever off.
Observed Results:
The piston retracts, but then extends and retracts ad infinitum.
Expected Results:
The piston retracts, ignoring the observer's pulse since it (should) be occurring at the same tick that the piston head is retracting.
Screenshots/Videos attached:
Yes
Notes:
This is a borderline case of bug/game design issue. It seems that to fix this, the observer clock linked in the bug report above must be broken, unless some special exception is made.
Linked issues
is duplicated by 5
MCPE-28595
Piston heads treated as solid blocks when passing in front of Observer
Resolved
MCPE-28683
Observer Piston Loop
Resolved
MCPE-29481
Observer Blocks detecting pistons and constantly fire.
Resolved
MCPE-29532
powering a piston by an observer into it now makes an infinite cycle of powering (destroyes any farm using observers)
Resolved
MCPE-40588
Difference in observer behavior between PC and Bedrock version
Resolved
Attachments
Comments 3
Based on the definition of observer behavior in the wiki, the piston block triggering will update the observer. So if a piston block was in a block observed by the observer, then it would update when the piston expanded or contracted. This does not apply to the piston head movement.
As quoted from the Wiki "A piston (not the head) extending or contracting" triggers redstone signal from the observer.
This is not the current behavior as of 1.2.5.15 - i.e. it is broken, according to your own documentation in the wiki. Please re-open this case and fix.
Thank you for your report!
However, this issue has been closed as Working as Intended..
This has been confirmed as working as intended. If you have a suggestion, please visit the Minecraft Feedback Site or choose a link below.
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