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Other ADA Gear => Step On It! => Other MIDI Footswiches => Topic started by: jimnastic on July 08, 2018, 02:37:20 PM

Title: DIY midi controller for MP2
Post by: jimnastic on July 08, 2018, 02:37:20 PM
Hi again,
Apologies for cluttering up the Mp2 forum, and please let me know if you think it would be better placed elsewhere! But...
I couldn’t get my hands on an ADA midi controller for my MP2 and just had to use it for gigs. So, I built one!
In short, it uses ArduinoCode and Atmega mega to recall 10 program change messages and 2 “pedals”, one CC midi Volume and 1 which I assign on a patch by patch basis for things like wah, chorus depth or fx loop levels.

Most of the info is found on the web, but if you’re on with a soldering iron it’s pretty easy to put a specific controller together that fits your needs.

If anyone is waiting for that ebay bargain midi controller to pop up INSTEAD I highly recommend thinking about a DIY effort to make use of all those glorious MP2 parameters waiting to be twiddled with live!
If anyone is interested I’m happy posting up more details or some drawings or code? (I’ve tried attachinga photo which is my “prototype!”)
Title: Re: DIY midi controller for MP2
Post by: vansinn on July 09, 2018, 09:26:30 AM
Cool project :bow:
Yeah, let's see some pics of the wonder..
Title: Re: DIY midi controller for MP2
Post by: Kim on July 09, 2018, 03:28:57 PM
Yes, very cool project idea.   :thumb-up:

However, we're not seeing an attached photo.....
Title: Re: DIY midi controller for MP2
Post by: rnolan on July 10, 2018, 02:57:31 AM
Hey jimnastic, lots of interest here  :thumb-up: , great project.  Weve been having some issues with attachment limits for a while now, you should be able to post 20MB but lately (regardless of the forums settings) it seems limited to 1.5 MB or maybe a little more.  If you try attaching a photo and it won't work, try reducing the size (and meanwhile maybe Dante can get our hosting ISP to work out why we are being limited  :dunno: ).
Title: Re: DIY midi controller for MP2
Post by: jimnastic on July 10, 2018, 12:17:50 PM
hey,
so here's a picture of the prototype and a schematic. A bit of code is also needed for the Arduino but that isn't going to prove too interesting unless you want to build it :)

basically i just recall 10 preset MP2 patches (is that what you do on the MXC?) and use the 2 foot pedals (one is a modified wah/volume) to do stereo volume "globally" and each patch has a specific parameter (like a fender tone with pedal mids control)

Anyone use a midi controller on the mp2 and got any useful tips/uses?
Title: Re: DIY midi controller for MP2
Post by: MarshallJMP on July 10, 2018, 03:23:58 PM
How do you calibrate the foot pedals?
Title: Re: DIY midi controller for MP2
Post by: rnolan on July 11, 2018, 05:37:54 AM
Hey jimnastic, I use the ADA MXC with a ADA exp pedal (stereo master vol) and a ADA quad switch (basically the pedal pack it came with).  The quad switch buttons can be individually set to toggle or momentary.  Mine are all default (toggle on/off, and assigned to loop/chorus/tremolo/tuner mute (I very rarely use them)).  And I use the pedal as a overall master vol (this I use always, so don't need tuner mute, just turn pedal off).The MXC (like it's predecessors) provides bank up/down and 10 patches within the selected bank (0 thru 9).  I (99%) stay in 1 bank of 10 patches.With the MXC, you can adjust the pedal range calibration, basically sweep it from top to bottom so the MXC knows its extremes (sort of what MJMP is asking about).  You do this once for each exp pedal (as you can have 2 and say put one on the wah, I use the triggered wah (lazy LoL), works fine for the rare occasions I use it.  The ADA exp pedal also has a soft switch (at full press) which will toggle things it's assigned to (eg Wah on off).
MikeB has been doing some funky things with his FCB1010 and TCGmaj2, like sweeping a pedal controls 2 CCs increasing 1 parameter while decreasing another,  the MP2 macros offer up some of these possibilities also IIRC.  Personally I'm keeping it very simple these days, 3 or 4 patches, a little light stereo delay and some reverb, chorus in the ADA for clean sound and that's about it....

Post the code for the Arduino, some here will be interested  :thumb-up: and may well build one.
Title: Re: DIY midi controller for MP2
Post by: jimnastic on July 11, 2018, 06:12:29 AM
ah, thanks for the explanation. Well, the MXC is SORT of easy to re-create, then!

To answer the question on how you calibrate the pedal (assuming you mean the continuous control by the "sweep") you define an analogue input on a pin, give it a name, then tell the code to divide the 0-5v (which is what the potentiometer is doing) in to 8 bits which gives you a digital value between 0 and 127.

Define an "output" (so a Midi address, for volume 21) and tell the MP2 to assign it to a parameter.
Some code below associated with that....

Title: Re: DIY midi controller for MP2
Post by: MarshallJMP on July 11, 2018, 12:46:02 PM
Okay I understand that but most foot pedal don't sweep the whole range of the potentiometer, so no full 5V sweep. Like the MXC has a calibration procedure where you have to sweep the pedal so it knows what the min and max is of the sweep.
Title: Re: DIY midi controller for MP2
Post by: jimnastic on July 11, 2018, 12:52:42 PM
I'll do some measurements and come back to you....
It's probably never going to completely replace an ADA controller, but you can make one dead cheap and just might be an alternative to waiting for ebay to come good! ;)
Title: Re: DIY midi controller for MP2
Post by: MarshallJMP on July 11, 2018, 03:38:04 PM
Okay great ! :thumb-up:
Title: Re: DIY midi controller for MP2
Post by: jimnastic on July 12, 2018, 08:55:06 AM
ok (ignoring the wonders of the switching and the code) the cheapo Wah volume pedal I ADApted has a 100k pot (which is slightly more than normal midi controller pedals).
Running from the 2 ends of the pedal (which has no adjustment) I get midi 0/1 and midi 127 as seen by the ADA, so it works by stealth :)
I note that if you buy an M-audio pedal (£14) you do have a "range" control similar to how you're describing. I believe this is another pot in parallel, but haven't taken one apart.

If i needed to adjust the range (and did this when I replaced a noisey pot on my Cry Baby wah) the range is a physical adjustment on where the pot gear meets the lever-y thing.
So either way, if you wanted to adjust it is possible, but for a volume or wah, full range for me works.
Title: Re: DIY midi controller for MP2
Post by: jimnastic on July 12, 2018, 10:00:18 AM
 :facepalm:
Just realised (actually thinking before I type!) a range pot would be potentiometer in series...
Title: Re: DIY midi controller for MP2
Post by: rnolan on July 13, 2018, 02:29:23 AM
Page 4 of the MXC manual describes the initial set up for the CCP sweep range and soft switch pressure.  It's stored in the MXC.

Title: Re: DIY midi controller for MP2
Post by: MarshallJMP on July 13, 2018, 10:24:19 AM
It seems some pedals can sweep the full range of the pot and some don't, the ADA CCP doesn't seem to do this, so that's why there is a calibration. A Boss FV500 (exp out) has the full range.