Relay Switching build report - ASMOP inspired success

[Chico]

I just built an 8 loop relay switcher that is based heavily on the information published by RG Keen over at geofex.com

I also included a few extra goodies, like a 433 mhz wireless transmitter.  The wireless feature was a PITA to incorporate, but now that it is done, it was a cool learning experience.  I have only tested this thing in my house, but I let is sit for over 6 hours without loosing sync.  I have also only tested it to a range of around 100 feet, but suspect I can get a reliable range of about 200-250 feet or more.

Basic features:
wireless or wired communication with footboard (transmitter)
Atmel ATMEGA16 microcontroller in transmitter and receiver
8 relay switched loops
72 programmable patch loctions
jumbo numeric LED displays on transmitter and receiver
two modes 1: select a bank and patch and the preset stored therein is loaded
2.  Loop mode, each of the 8 footswitches controls its respective loop.  This can be a "master preset" or it can be used to toggle effects in/out where a preset has not already been programmed.

Programming is carried out on the receiver with a real easy program interface.  There are 8 toggle switches and leds (one each to switch the loop in or out).  There are also buttons to select the bank and patch.  Press the STORE button, and the state of each relay toggle switch is read and stored in an EEPROM corresponding to the selected bank and patch.

Check out: //www.circuitmuse.com

There isn't much info at this site yet (just got it set up today- and do not have a clue how to create a web page), but there are a few pix and a few general explanations.  I will be updating the site with schematics, code and more detailed explanations over the next few weeks.  

If anyone has any ideas for future implementations, comments or suggestions, please let me know.  This thing is very much a work in progress and is still in the prototype stages.

That said, it works completely as advertised.  Bottom line, go read all of RG's posts on Relays and on the various switchers and ASMOP implementations.  There is enough there to let you customize a switching system to whatever your particular needs are.  Thanks to RG.

Best regards

Tom

[niftydog]

nice work, dude. I'm working on something similarly inspired myself. Always good to see what others guys are doing, gives me ideas!!!

[Transmogrifox]

very cool.  I have been throwing this around for a while...trying to determine whether I want to use relays or  some kind of active device...relays are just so expensive.

Anyway, the thing that makes my desired dream project so large is that it allows me to select any pedal sequence as well as offering a parallel mix for any and all configurations without ever having to unplug a pedal.  It requires a large Relay matrix, not to mention the program debugging after coding.  Kind of a module thing, similar to Digitech RP-20 module menu, except the analog multiplexing problem becomes much more complex than mere programmed digital multiplexing.

[Chico]

I think RG has something on his site with regard to what you are talking about.  

Currently, my effects are in a fixed order, but I can turn on or off any combination of the loops.  I thought about the idea of not only loop selection but allowing a total "rewiring" of the effects order, but thought I would try to get a handle on something a little easier first.  Also, I wanted to try to work out the bugs on the wireless switching, which I have been testing for several weeks with solid success.

In that regard, I have more schematics up.  
Check out //www.circuitmuse.com

My web programming has a lot to be desired, but there should be enough information now to build the complete project.  If not, please let me know and I will be glad to help in any way I can.   I have not yet included all the software etc. because there is such a wide variety of AVR/PIC and other microcontrollers that can do the job, but based upon the schematics and what features a person desires, this will get them in the ballpark.


Good luck with your project and let us know how it turns out.

Best regards

Tom

[R.G.]

Thanks Chico - yes, there are actually two items on GEO allowing any order of effects.

There is a manual, no microcontroller required one and a uC one.

[Transmogrifox]

Thank you guys for the information you provide. The biggest obstacle in this process is time (naturally).   As tom can probably verify, even the more simple system is likely a very time-consuming process in terms of design.  The actual construction time is pretty short in comparison.  

It's encouraging to hear the wireless stuff is working out for you.  My RF classes did more to scare me away since any DIY radio stuff requires a little more careful planning and usually a well-designed PCB, however this stuff is significantly simplified if you use a tried-and-true transmitter/receiver like you have done.

[Lonestarjohnny]

Chico, that's mighty impressive, your testing look's to be very positive, thank's to RG I've comeup with somethin for my Pedal system that look's like on paper it'll work very well for what I need,
Thank's for shareing this, it's helped me alot.
Johnny

[Chico]

Transmogrifox:

I hear what you are saying.  It took me about three months start to finish to get this switcher off the ground, plus a lot of "thinking time".  

I also like the idea of loop sequence/parallel mix selection. I am going to have to pour through RGs articles again before starting Switcher Version 2.0.  That said, I have been spending some time with RGs OTA primer, so I would not be suprised if my relay switcher version 2.0 also includes software controlled mixing and panning in addition relay switching :twisted:

Lonestarjohnny:  The great thing about the way RG presents information is that if you take the time to let it all soak in, you have the tools you need to create your own custom tailored effects from the ground up.

Let us know how your project turns out.

Best regards

Tom

[Transmogrifox]

Yeah, I agree that RG has done a great service to help people be creative with musical electronics.  I have had the privelege of studying electrical engineering for 4 years and understand the concepts, but I would be WAY behind where I am now in terms of creatively applying it if it weren't for people like you (Chico) and RG, Mark Hammer, Aron...and the list goes on for the people who share the fruit of their hard work and creativity.

I know that if I had come upon this site when I had no clue about how electronics and such, it wouldn't be long before I found all the information I needed to start from the basics, learning to build, learning to design, learning to create.  It's all here and you guys do some very phenomenal work.  I see some of these more ambitious projects such as this switching unit, and the big super ROG simulator amp and all I can say to you guys is:  MUCH RESPECT.  keep it up  :wink: