minecraft-java-editionminecraft-redstone
I know that sounds very confusing, but I have a few examples. I want it so that I can flick something like 3 levers and have the output be the leftmost one.
If I flicked the first two, the middle one would turn on, and if I flicked only the right one, the right one would turn on. During this, all of the other ones would be off.
Here are some examples:
I could use either command blocks or survival redstone.
I was bored, so decided to make this monstrosity of a redstone circuit:
Edit: Now that Redstone Repeaters have been added to the game, even by following this design, sections 3 and 7 could be greatly diminished (as those sections are basically just repeaters).
This circuit will accomplish what your question is asking. I will explain each section of the circuit:
This is the pressure plate the player will stand on. The end result is that your door will open if the player is standing on it, and will close when the player steps off. Also, if a certain amount of time passes by, the door will close even if the player is still stepping on the plate.
These are known as edge triggers. If they receive an input, their output will flash for one tick (redstone timing is measured in ticks) and stay off after that, even if the input is still receiving power.
This may look like a mess of NOT gates, and that's because it is a mess of NOT gates. Specifically, it is a mess of an odd number of NOT gates. This is known as a clock generator. A clock causes its output to cycle on and off continuously. The number of NOT gates in it determines the duration of the cycle (more repeaters equals a longer time spent on and off).
The clock is off, because 3a is sending it power. If the player were to step on the pressure plate, 3a would turn off, causing the clock to begin cycling.
This is one of the ways you can adjust the inactivity timeout - if you need it to last longer, add more NOT gates, and vice versa.
Note that this device is multiple levels, most of which are not shown in this image. I only included it as a visual aid to show its input and outputs. If you build this circuit and wonder why it doesn't function, this is why.
This is a binary counter. Every time the torch at 4b, receives power, it counts in binary. This is the reason you need the clock - so the input will flash on and off, causing the binary counter to...count. The first flash causes the rightmost torch to turn on (00001). The next flash results in 00010, then 00011, 00100, etc. 4a is the binary counter reset, causing the torches to read 00000. This ensures that when the player steps on the plate, the counter will start fresh.
Because you will have to build a binary counter that actually works, see the schematic of one from this thread on the Minecraft Forums.
Adding or removing more bits to the binary counter is the other way you can adjust the duration of the timeout.
Basically, when the binary counter reads 11111 (all of the torches are on), 5a will turn on, causing the RS-NOR latch at 6 to turn off regardless of whether or not the player is still on the pressure plate (RS-NOR latch explained later).
This is an RS-NOR latch. It is effectively a 1-bit memory cell, storing either a 0 or a 1. When the block in the bottom-left corner of it receives power, the switch flips into the 1 position, causing the door to open. When the block in the top-right receives power, the latch resets, causing the door to close.
This is just a bunch of repeaters (two NOT gates). The only reason for this is so that the signal going around the right side of the circuit reaches the RS-NOR latch before this signal. If there were no repeaters here, the RS-NOR latch would switch into its on state, and then switch off right after due to being reset.
Oh look, it's finally the door!
In summary, this is what happens:
Then, if the player were to step off of the plate, the wire wrapping around the right side would turn on again, causing the RS-NOR to turn off and, consequently, closing the door. Additionally, if the player continues to stand on the plate and the binary counter reaches 11111, the torch at 5a turns on, also causing the door to close.
I'm sure this circuit could be made much smaller and more efficient, but this is a proof of concept.
It sounds like a problem with this 2in/1out "device". I would do two things:
1) Try setting it all up in a smaller area and see if the problem persists. There might be some game bug or design flaw caused by the long distance. Also it will be easier to do "debugging" on the circuits if it's all collected in one place.
2) Post a schematic of the device since it is very hard to help without seeing the actual circuits.
Update:
From patch notes for latest patch 1.7.3
Booster rails are no longer being powered magically without a power source
So updating your client might fix the problem now.
Best Answer
Here it is the system:
And here it is, missing one layer:
I made it so you could loop it and repeat as many times you want. Dark blocks need to not be a transparent block (such as glass or slabs) and need to be there (cannot be missing), light ones can be either and quartz do not matter. There is nothing under the torches that are close to the Lamps.
Basically it's a chain reaction. Because of how repeaters work (Input can only come from one side and output leaves from another point). you came make that the far left turn off all the torches to his right. making them 'unusable'. It would be way easier to make it with commands but I wanted to make survival friendly. If the system looks confusing in any way, I'll gladly post more screenshots. Hope it helps!.