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New midi pedal and patchbay

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MarshallJMP:
In 2018 I had to make a thesis for the bachelor in embedded systems I was doing, so I asked the other guitarist in the band to file a project for me at my school. He has his own company and I needed to make the thesis for a company so he filed a project which involved a midi pedal and switcher. So I jumped on it  ;D
I finished it in july 2019, explained it all for the jury and was rewarded a 17/20. Since then it has been on my pedal board and in my rack and it working fine. So maybe it's time to do a show off.  8)

My intention was to make some sort of upgraded version of the MXC pedal and the patchmate, get rid of all the things that annoyed me and put some things in I missed.
I wanted to make it as simple as possible both electronically as operation.

Starting with the MXC, I got rid of the quad switches and build these inside the pedal, made the editing so I can do changes on the fly, no more 9+... to alter things. I use a edit button in stead now, push it for 2 seconds and you are in edit mode, all can be done with your feet now. Also put the edit info on the pedal so no need to search for that damn manual. Got rid of the delay filter and pedal switch range and added a display test and you can also program the display intensity. Altered the pot range setting so you don't need to sweep it but set it to minimum and store, maximum and store. I always felt the the sweep didn't work correctly. It also has 2 inputs for sweep pedals. And last it does have a 7 pin midi connector to allow phantom power but it also has a DC jack for power. It does midi program and control change, fully programmable.

Electronic wise it kept it to a bare minimum, a pic µcontroller running at 32MHz (8MHz crystal with a internal PLL inside the pic to bump it up to 32 MHz) an I/O expander (SPI bus) and a few connectors,resistors,caps, crystal and a 7805. It has a 8 digit LED display also on a SPI bus. I also kept a space for some external memory, maybe I install a alpha numeric display so you can put some names in it and display these. The pcb is 11 x 7.5 cm.

MarshallJMP:
The midi controlled patchbay, although the patchmate was good there were also things that annoyed me, first the relais are a bit noisy when they switch, nothing really bad but still, operation is quite complex. So I started out with better relais, smaller and more quiet and the operation is far less complex. On the front you will see two rotary encoders with a push button integrated , and LCD and eight push buttons with led's inside the button. On the back you have eight mono/stereo loops, dual mono out, a midi in and two midi thru outputs so you can devide the midi signal if you have multiple midi racks. Unit has midi control and program change and is fully programmable.
I also have build in a few power supplies for my racks that use external adapters and the phantom power for the midi pedal (7 pin din).
Operation is very easy, push one or more of the eight pushbuttons that correspondent with one of the eight loops, select the program number with the right encoder and push it, and it will be saved under that program number. Each loop can also be controlled by a midi control change number (can be programmed to any number) . You can set the midi channel and it also has a build in midi monitor (like the MP-2 has). Menu can be accessed with the left encoder, only 4 menus, working menu, set midi channel, set midi control change number  and the the midi monitor.

Electronics, also quite simple, again a 8 bit pic µcontroller at 32MHz, optocoupler, 7805 and 7806 74HCT14 buffers, ULN2803 driver (relais), 16 relais, LCD, caps resistors, stacked jacks and a few transformers (toroid). All relais and Ic's in sockets for easy maintenance. All interconnects with flat cables.

All programming done in C pro for pic. PCB's made in Autodesk Eagle.

bunkyloo:
Those are both really nice you should market those!

MarshallJMP:
Thanks Bunkylo but it's too much work to make them by hand, I could go to a factory but you need to build at least a few hundred to keep the cost low. The electronics is not a problem, it's the mechanical stuff like the rack and case and front panel of the midi pedal.

rabidgerry:
This is amazing work!  I wish I had those skill you have.  Really superb stuff MJMP.  :thumb-up:

A really good useful project to have worked on.

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