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threeway Switch

I have this switch it goes 3 ways, I am a noob and just started learning about electronics. I have a small oled Display connected to my nodemcu which is displaying information. The middle switch is off right? So I want the middle switch to turn the display off, the left switch to show specific information and the right switch to make the display show other information. How exactly do I wire it?

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I would call that a single pole, double throw (SPDT) center-off toggle switch. Electrically, it looks like:

schematic

simulate this circuit – Schematic created using CircuitLab

To confuse newcomers, when the handle is to the left, the center terminal is connected to the right terminal, and when the handle is to the right, the center terminal is connected to the left terminal.

With the handle in the center position, there is no connection between any terminals.

suggested connection:

schematic

simulate this circuit

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  • \$\begingroup\$ Ok thank you but which of the nodemcu‘s pins do I have to connect where on the switch? \$\endgroup\$ – Tanonic Jan 6 '18 at 21:55
  • \$\begingroup\$ I would connect the center terminal to Ground, and a 5 - 10K pull-up resistor from the left and right terminals to the positive supply. The left and right terminals would also be connected to whatever digital input pins on the nodemcu you want to use as inputs. \$\endgroup\$ – Peter Bennett Jan 6 '18 at 22:05
  • \$\begingroup\$ So connecting the left to a data pin with a resistor and connecting the right to 3,3V with a resistor and connecting middle to gnd would work? \$\endgroup\$ – Tanonic Jan 6 '18 at 22:36
  • \$\begingroup\$ @Tanonic - see schematic in edited answer... \$\endgroup\$ – Peter Bennett Jan 6 '18 at 23:06
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Your device has two switches inside, connected to three external terminals.

The center terminal is common to both switches, and the two ends are at the other ends of each of the switches. When the toggle is in the center, both switches are open. That means all three terminals are disconnected from each other. When the toggle is to one side, the center will be connected to one of the two outer terminals. When toggle is to the other side, the center will be connected to the other terminal.

The rest is up to you. This device has three states it can be in. You can certainly detect with of the three states. What you do with that information is up to you, and it's not clear what exactly that is anyway.

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Since the paddle is in the middle, I think that it is a 3 position switch (SP3T)(single pole tripple throw).

Here is a very rough diagram of the switch

The red slider moves when you tilt the paddle to either side and shorts out two of the blue contacts.

In center position, the slider does not touch either of the side contacts.

enter image description here

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  • \$\begingroup\$ I'd still calll it an "SPDT center off". "three position" means to me that there are three active positions - three possible paths through it. This switch only has two active positions, plus "Off". \$\endgroup\$ – Peter Bennett Jan 7 '18 at 20:31

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