caltabid / MidiPedalBoard

USB Midi Pedal board based on STM32 with 10 buttons, 8 potentiometers and 2 expression pedals

MidiPedalBoard

Overview

This repository contains a USB Midi Pedal board based on a STM32F407G-DISC1 with 10 buttons, 8 potentiometers and 2 expression pedals

It is USB MIDI class-compliant, so you can add MIDI port without drivers(Windows, iOS, Android, etc...)

The USB-MIDI Class Driver is based on mimuz-tuch project (c) D.F.Mac. @TripArts Music.

I got great inspiration from 2 open source projects:

• USB-MIDI Interface 8IN/8OUT for STM32 CureMIDI8
• Arduino MIDI Footswitch

Specifications

Features

• 10 buttons (9 general purpose + Page2)
• 8 potentiometers (7 general purpose + Mode)
• 2 expression pedals
• USB MIDI class-compliant

How to use it

• Page2/Looper Btn
  • When activated (Led on) use second page for other buttons
  • No CC is sent when pressed
• Mode potentiometer (#8, the last one)
  • Left => Normal mode: Btn sends 127 when activated (Led On) and 0 on deactivation
  • Right => Bypass mode: Btn sends 0 when activated (Led On) and 127 on deactivation
  • Half => Disable potentiometers CC
  • No CC is sent when rotated
• Button CC values (excluded Looper/Page2 Btn)
  • {51, 52, 53, 54, 55, 56, 57, 58, 59}
  • {61, 62, 63, 64, 65, 66, 67, 68, 69}
  • Buttons 65 to 69 (Second page, front buttons) are stateless and only send value=127, this is better for some looping commands
• Potentiometers CC values (excluded Mode Pot)
  • {18, 19, 20, 21, 22, 23, 24};
• Expression pedal CC values
  • {16, 17};

Building Information

Making hardware

See Presentation

Basically you should work some wood:

And connect about 30 wires:

Building software

Install STM32CubeIDE, import Project files. When building the binary file will be created in /stm32/Debug/ or /stm32/Release/

File Location

• Binary file for STM32F407G-DISC1
• STM32CubeIDE Project file
• Documentation

NOTICE

VID/PID

Vendor ID(VID) and Product ID(PID) in <usbd_desc.c> should be unique pair for each USB devices. Default VID 0x1209 and PID 0xDACA is experimental IDs from http://pid.codes . When distributing or selling, you must get your own IDs, and change to your own IDs in order to avoid conflicting to other USB devices.

Copyrights

• USB MIDI Class Driver by D.F.Mac. @TripArts Music
• STM32Cube by STMicroelectronics
• USB buffer libs by Keshikan (http://www.keshikan.net/)

Author

(c) 2021 Daniele Caltabiano ( Website )

License

• USB MIDI Class Driver: CC BY 4.0
• STM32 CubeF4: BSD-3-Clause based.
• USB buffer libs: GPLv3
• Other Codes, Hardware, Schematic: MIT

See also LICENSE.md

Update History

• (2021/05/21)
  • Added documentation in pdf format, improved readme and fixed code structure.
• (2021/05/19)
  • Initial Release.