mojira.dev
MCPE-15607

Pistons take 3 redstone ticks to extend and 1 tick to retract, which should both take only 1 rs tick

The screenshot shown below is a falling-edge detector which should emit 2 ticks pulse on a falling-edge and shouldn't emit a pulse on a rising edge.

[media]

The repeater is set to 2 ticks delay. On a rising edge the piston should take 1.5 redstone ticks to extend so there should be no pulse emitted from the output. On a falling edge the piston should retract instantly (0 redstone ticks) so there should be 2 ticks pulse from the output.

However in 0.15.0, pistons take 2.5 or 3 redstone ticks to extend and 1 or 1.5 redstone ticks to retract, so the said circuit instead acts as a 1 tick dual-edge detector.

According to a developer, it might be a result of the redstone circuit ticking separately from the block entities (piston). During the 2 tick: Redstone ticks first, which will propagate the repeater. The piston ticks afterwards placing the moving block as full block.

Related issues

Attachments

Comments

migrated
[media][media]
migrated

I suspect that this one and MCPE-12848 stems from the same root cause.

SuperGeniusZeb

Revised title to be more accurate to what the intended piston timings are for Bedrock Codebase.

HelenAngel

This was closed by the design team as works as intended.
Explanation below:
"It takes exactly 2 rTicks to retract, but because the pulling piston starts retracting (toggleMechanismTiming example) at that same tick, the ticking order is scrambled (as designed) therefore the result is undefined."

migrated

Thank you Helen but I don't think that is correctly explaining the behavior because the circuit always emits pulses of the same length and not randomized. However, I just found the following modification perfectly fixes the problem so this turned out to be in fact another instance of MCPE-15793.

[media]

So yes, the ticket can be safely closed either way.

migrated

(Unassigned)

24797

Confirmed

Tablet - iOS - iPad 3

game-tick, piston, redstone, redstone-tick, redstone-timing

0.15.0, 0.15.4, 0.15.6, 0.15.10, 0.16.0, ..., 1.0.4.1, 1.0.4.11, 1.0.5.3, 1.0.7.0, 1.1.0.9

Retrieved