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3 Programs with an SPDT ON-OFF-ON Switch

Posted: Wed Mar 08, 2017 1:24 pm
by smear
Hello,

In my FV-1 designs so far, I've used an SPDT ON-ON switch to select between two presets. However, a lot of pedal manufacturers seem to get three presets using a SPDT ON-OFF-ON switch, and I simply can't seem to figure out how they're doing it. Do I not actually need to ground the pins for them to be in the 0 position?

Here's the setup that I'm currently using:

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Thanks!

Posted: Wed Mar 08, 2017 1:57 pm
by Aaron
If you connect 3.3V to pin2 on the switch, have pull down resistors on S0 and S1 and connect both of these to pins 1 and 3 on your switch.


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Posted: Wed Mar 08, 2017 2:28 pm
by smear
Thanks for the fast reply Aaorn, that makes perfect sense!

So to put my mind at ease, this would do the trick?

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Posted: Wed Mar 08, 2017 3:44 pm
by Aaron
That looks like it will do the trick. This should give you access to programs 0-2.

Posted: Wed Mar 08, 2017 10:55 pm
by smear
Great, thank you so much!

Posted: Thu Jun 29, 2017 3:50 pm
by BuGG
This is exactly how I do it. The cool thing is that you can use a SPDT On-On switch when you only need two modes, or On-Off-On when you need three. No further circuit modifications needed.