Parallel Switches without Interference?

[lars-musik]

I recently built a triple pedal (three circuits in a box). The individual circuits are bypassed by µC controlled relays, activated by momentary switches. Now I would like to have a jack ("remote") to hook up an external switch that activates or deactivates all three.
Is there a way to avoid interference with the "regular" bypass switches? Some diodes or such? Can it be done at all?
If it helps, this is the bypass switching I used:

https://github.com/matt-garman/mcu-relay-controller

[FiveseveN]

Are you saying you have three separate bypass systems, each using a uC? Surely there's a more efficient way to do that. If you consolidate to a single uC you can add another input and program it to do whatever you want.

[R.G.]

If there is already a uC on the relays, just change the code so that they get the signal to "everybody turn off now" on a pin.

If you don't have access to the code, put on a relay that bypasses the whole mess.

[lars-musik]

Thank you for your suggestions. I still want to be able to switch the circuits individually on the stomp box, yet have another, optional,switch to turn them all on at once. I am afraid, my programming skills are less than zero. A mechanical solution would be highly welcome 😁

[Eddododo]

Thank you for your suggestions. I still want to be able to switch the circuits individually on the stomp box, yet have another, optional,switch to turn them all on at once. I am afraid, my programming skills are less than zero. A mechanical solution would be highly welcome 😁

Well of the external switch will exclusively be used to engage/bypass all three EFFECTS, then you can basically just have another set of  relays that just short across the other switches (as in connects pre switch node  to post switch node)

If you still want the foot switches to work while the external switch is ACTIVE, then it's time to learn some more (this is DIYstomoboxes, after all) or else ask a friend or someone on fiverr to do some programming for you.

[ElectricDruid]

You don't have to do it with relays. The relays are controlled with MOSFETs, and the MOSFETs are controlled with 5V pulses from the uPs.

You could set up a diode-OR connection for the "Set" coil MOSFETs to turn all the relays on (or similarly for all the "Reset" coil MOSFETs to turn everything off) and then you'd have inputs that would do what you want.

[R.G.]

There's a bit of a problem with just driving the set/reset MOSFETs. Depending on what the controller is trying to do, this will at least make the controller lose track of what state the controller thinks the relay is in; at worst, it might drive the "reset" line at the same time the "set" line is being held solid by the controller if the controller isn't pulsing the relay. This could get the relay into a halfway state so it doesn't know which way to land, or even conceivably overheat the coil or make it vibrate.

Ask me how I know this.   8-)