A new MIDI Switcher - JAS (just another switcher)

[gtudoran]

Hello guys,

Long time no talk around here, as i had a lot to fix in my life Now i have a new project on bench and that is a MIDI switcher. This is build for a customer of mine, witch had a very specific request:
- should change amp channels
- should change a bunch of pedals in amp's FX loop
- should use note on/off to change the configuration as he sing a song. And this is accomplished with a click-track (from a computer with midi interface) witch will send me note on/off events, and so the configuration(amp+pedals) will change according to the needs of the player.

Solution: the first thing that came in mind was - store PORT value in EEPROM and then call it according to the note on, but this required a pair of port_value and note_on_value to be stored ... hmmm not too easy to program (it was not impossible, but it was too much work and i'm a lazy person). The solution: why not dump note value as a port value, so all in all this would be like PORT_VALUE=MIDI_NOTE. We have notes from 0 to 127 that would be 7 bits of on/off, and you can translate that in 7 relays witch will control a maximum of 7 pedals in the loop, but the request was clear ... should also control AMP CHANNELS .. well MIDI notes come with another info and that is VELOCITY witch is also a value from 0 to 127 bam bam so we have our info.

-NOTE VALUE for PEDALS
-NOTE VELOCITY for AMP CHANNELS

And this is how a small and simple switcher was born. The core is an ATMEGA 328 (you can use without a problem ATMEGA 168, as the whole HEX will not exceed 9-10k from a total of 16k for ATMEGA 168 - ATMEGA 328 would be a waste).

Here i will post the schematic and board file:
SCH: https://dl.dropboxusercontent.com/u/15275178/MidiSwitcher/mdi_sw.sch
BRD: https://dl.dropboxusercontent.com/u/15275178/MidiSwitcher/mdi_sw.brd

My board use AXICOM IM03 smd DPDT relay to have a total of 5 pedal loops, as for the amp channels i will duplicate the board and use only a pair of contacts(a little waste but... life is life) - you can use any DPDT relays with little modification to the board.
I will also provide the HEX file (i will upload it tonight) witch will respond to NOTE ON events. At request i can modify it and respond to ... PC events for example.

Any question will be answerd and i will be more then happy to do so 

Best regards,
Gabriel Tudoran
Analog Sound

[gtudoran]

And here you have some pictures with the modules and a little piece of the action:

and here, are some pictures: https://plus.google.com/photos/105439259150041381490/albums/5955074447936653377

Best regards,
Gabriel Tudoran
Analog Sound

PS: The MIDI interface was a cheap USB to MIDI but any device that is able to send MIDI is OK.

[Wlat]

Awesome work! Don't know why I never noticed this post before, but you certainly have my attention now! Any chance on an update?