Steps to reproduce
Place a comparator and a line/web of redstone dust that connects to the back and side inputs of the comparator, and a separate redstone dust line at its output.
Place or activate a redstone power source in a position that makes the redstone power level at both comparator inputs be the same.
Repeat this setup each direction and with the comparator in normal and subtract modes.
Repeat the setup again but add a second comparator pointing the same direction but farther from the power source such that the redstone dust input at its back is at a higher level than the input at its side.
Expected result
The comparators always calculate the correct output.
Observed result
Half of the comparators calculate incorrect ouputs, and they go wrong in different ways depending on whether they are aligned with the X or Z axis.
Subtract mode on comparators does not function when the main input and side input of the comparator are connected redstone, and when the comparator is facing east or west. The same is when it is not in subtract mode.
Linked issues
is duplicated by 16
Attachments
Comments 10
This issue appears to be limited to situations where both the back and side of the comparator are connected to the same power source. It doesn't matter the orientation of the comparator. If the power source is the same for both sides it seems like the comparator only wants to push through the power that is connected from the north or south, ignoring completely the east/west sources. which means a signal strength of 2 from the side could completely cut off a signal strength of 15 from the back.
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With independent power inputs on the sides, it works correctly and is not directionally dependent.
A common power input will work correctly if there are inputs on both sides.
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(Testing done with output facing south on XBOX One S)
A second comparator used as a buffer can act as a temporary fix to the comparator breaking from two inputs from the same source. In builds that require specific input strengths you could just put a comparator on both inputs to work around the bug (Note: some things cannot be fixed using this method such as anything limited by size e.g. comparator clocks, comparator XOR gates).
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Windows 10 v1.19.50
1.
This also has some strange effects when it comes to comparators reading a signal from a container. Usually, the container overrides the value from any redstone lines, and that still happens. But when a redstone line is connected to both inputs of the comparator, and the comparator is reading from an container, bug is present (see images). Hopper has 1 dirt in it.
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2.
I tried to map out multiple input and output values of the comparator, but it is highly dependent on many factors which should not affect the output. In particular, the positioning of power sources plays a large rule, and the orientation does play some rule. Sometimes adding a power source with does not affect the inputs to the comparator will change the output of the comparator. It seems that a part of the issue may be which power source is being chosen as the input. I also never say an output value greater than 7 (implies mod/sign issue to me, but other issues make it hard to figure out exactly what the problem is, especially without code.).
Pls repair. The best XOR gate in the game is using this property of the comparators. My circuits are useless right now :c
Edit: (reply to Jaida's comment)
Thank you very much. That enthusiast me very much ♡
(reply to Helmut Joaquín Pfeffer García's comment)
if you're talking about the two comparators next to each other on subtract mode you can do a temporary fix by putting two extra comparators on the back and side inputs of both comparators. It makes the circuit bigger but it's the best you can do until it gets fixed
please fix this bug, im a Brazilian redstoner that have built some calculators for youtube, and now no one of them works. so i cant show for nobody, and my folowers that dowload my creations are thinking that it doenst work (i know that work, because before the aptate that this bug happen, all calculator work well)
Clearly the attempt to fix MCPE-81981 made it worse.