What do I even call this? Switching order of multiple (3) devices IN/OUT - Page 1
Forum section: electronics / projects

author: mkiijam
author_rank: Regular Contributor
timestamp: January 15, 2023, 05:31:15 am
content: I need to design a device that switches the order of hookup of three devices. i.e. A feeds B feeds C or B feeds C feeds A etc.I'm not even sure what to call this type of function for searching / research?

author: CountChocula
author_rank: Unknown
timestamp: January 15, 2023, 01:22:54 pm
content: Sounds like a switch array, or maybe a multiplexer, but the devil is in the details… what kind of connectivity exists between the three devices?—CC

author: Terry Bites
author_rank: Super Contributor
timestamp: January 16, 2023, 12:32:10 pm
content: Start by drawing up a truth table (Karnaugh map) to show the logical dependencies.Then you can design the logic.Test your circuit in simulator. eg KiCADMUXs can be used to implement any arbitrary logic expression.The control lines are the input values and the mux IOs set the output values.(sounds like he's stoned)If there are time dependencies you'll need a"state machine" to sort it out.

author: mkiijam
author_rank: Regular Contributor
timestamp: January 17, 2023, 06:02:52 pm
content: The specifics might help.It is to switch the order of audio devices in a chain of 3. Each has balanced audio connections.

author: 741
author_rank: Frequent Contributor
timestamp: January 17, 2023, 06:18:29 pm
content: I think I'd refer to this kind of topic as "Power Sequencing"

author: Terry Bites
author_rank: Super Contributor
timestamp: January 17, 2023, 07:35:49 pm
content: Like an FX chain?Would you want a single switch that cycles through the chain configurations?Clock a ring counter from the switch. Debounce the momentary switch with a 555 and clock the 4017 from it.Use the ring counter outputs to set analog switches (or relays if you have the power available).Here's a generic solution covering six possible chain scenarios. You can add bypass or all off by routing in to out via the matrix.Just add more states if you run out. LEDs indcating all your states are a wise investment.You can set the number of combination states by tyind the reset to Pn+1 Add leds to show the state selection.Make the matrix as complex or as simple as you need. Note that if you use analog switches you'll need dual rails.If you use relays you can run the thing off a single 5V to 15V supply. Less faff. Dont forget your diodes!

author: mkiijam
author_rank: Regular Contributor
timestamp: January 18, 2023, 06:25:26 am
content: Yes, like an FX chain.But, I think it would be better some how to be able to order them instead of cycle them. Perhaps there could be buttons 1-2-3 and buttons A-B-C. You would order them by pressing the desired position (buttons 1-3) and then the desired device(A-C)?

author: Terry Bites
author_rank: Super Contributor
timestamp: January 18, 2023, 09:18:59 am
content: Its a crossbar patch bay really. Just automated. You might find this kind of thing in ATE.This is for your "FX Router MK1"I thought about it a bit more about it. Heres a drawing of how it might work. Add the matrix options you need, I put all of them in as an illustration.If yoiu dont need so many options,then just simplify and ude fewer switch points.Sorry about all the random numbering! If I get time I'll tidy it up.A simple counter would need decoding in to operate node swtiches -a lot of faff.Its an ideal job for an arduino. Let it count the input and work out the relay/ analog switch configuration. Add a stunning LED display.You only need code for a look up table and a counter. Check out this- Job done ADG2188 ic. EVAL-ADG2188EBZ You can easily get arduino to control it..You can buy this thing linkbone.com/audio-matrix-switch-balanced-xlr/

author: mkiijam
author_rank: Regular Contributor
timestamp: January 19, 2023, 05:19:07 pm
content: Excellent! Thanks Terry!