Welcome!

My GitHub name is rppicomidi because I like to develop MIDI projects for the Raspberry Pi Pico and Pico W.

This website will direct you to my software and hardware projects for Bluetooth MIDI, USB MIDI, and old school serial port MIDI and to my software libraries that the projects use for user interfaces, for Pico W Wi-Fi, and for non-volatile storage. Most of the code is in C or C++.

What's New

12-Jun-2024 Updates

• There is a new application and a new driver:
  • midi2piousbhub Interconnect MIDI devices via a USB hub or old school MIDI. Configure the interconnections using a serial port console and save the configurations as presets in the Pico board's serial flash memory. Back up the presets to USB flash. The USB MIDI host is implemented using the RP2040's PIO modules, and the RP2040 native USB port is a USB device port that provides an additional MIDI I/O port (to use a virtual instrument on an iPad, for example), and a USB serial port for the command line interface.
  • cdc_stdio_lib Library allows a pico-sdk application that uses TinyUSB to add USB CDC stdio support. For example, if you are using the RP2040's USB port as a USB MIDI device, you can add a CDC class serial port interface as well. The stdio calls like printf will route output to the USB port, etc. The midi2piousbhub project uses this library.
• To allow Arduino applications to have an easier time configuring MIDI libraries,
  • usb_midi_host adds run-time buffer length configuration
  • EZ_USB_MIDI_HOST API has changed to a C++ template parameterized by a settings class

12-Feb-2024 Updates

• Due to recent bug reports enumerating USB Audio+MIDI devices, I have increased the default enumeration buffer size from 256 bytes 512 bytes, and I added a Troubleshooting section to the README.md files for each of the following projects:
  • ble-midi2usbhost
  • midi2usbhost
  • midi2usbhub
  • midi2usbhub-web
• Removed an erroneous report on yesterday's entry for this web page about a project that does not exist. Added an entry about an update to the midi2usbhost project.

11-Feb-2024 Updates

• usb_midi_host Fixed a bug that prevented MIDI devices that are designed with high-speed USB in mind from enumerating. The maximum full speed USB bulk transfer is 64 bytes. Two DSP guitar pedals assumed they were only hooking up to a high speed capable host and specified a maximum bulk transfer of 512 bytes. The code that attempted to correct this did not quite work. It is fixed now. Debugging this issue revealed that the default enumeration buffer set by CFG_TUH_ENUMERATION_BUFSIZE is too small to work with probably all audio+MIDI devices like DSP guitar pedals. Future versions of the C/C++ examples will likely bump up CFG_TUH_ENUMERATION_BUFSIZE to 512 bytes. Arduino examples require some hacking of the Adafruit TinyUSB Library. See the project's README file for more details.
• usb_midi_host This driver has the examples and documentation updated for use with either the pico-sdk or the Arduino IDE. Further, the examples will work with either the native RP2040 USB hardware or with a PIO USB host port. (Arduino sketches require the Adafruit TinyUSB Library) You can load this library using the Arduino Library Manager.
• EZ_USB_MIDI_HOST This C++ library code that lets Arduino sketches and C/C++ programs use the Arduino MIDI Library with the usb_midi_host library and the TinyUSB Library (Arduino sketches require the Adafruit TinyUSB Library) You can load this library using the Arduino Library Manager.
• midi2usbhost This project now supports a C code version and an Arduino version. Build the C code version with the pico-sdk. The Arduino sketch uses the Arduino IDE and the EZ_USB_MIDI_HOST library to do the work. The code is designed to run on a Raspberry Pi Pico board, but it should work on any RP2040 type board with minor modifications.

24-Oct-2023 Updates

• midi_uart_lib has been updated to move ring_buffer_lib to a peer subdirectory instead of a sub-directory of midi_uart_lib. This makes it simpler to coexist with ble-midi2usbhost, and pio_midi_uart_lib. I have updated the following project that use midi_uart_lib so they still build.
  • midi2usbhost
  • midi2usbhub
  • midi2usbdev
• pio_midi_uart_lib documentation has been updated to describe the output only MIDI port feature and to point to the midi-multistream2usbdev example.
• ble-midi2usbhost
• midi2usbhost
• midi2usbhub
• midi2usbhub-web

21-Aug-2023 Updates

• usb_midi_host An application level USB MIDI Host driver for TinyUSB. On 15-Aug-2023, TinyUSB was updated to include support for USB Host drivers added at the application level. I created usb_midi_host so I could avoid requiring people to use a forked version of TinyUSB to build my projects.
• Several projects updated to use usb_midi_host and standard TinyUSB instead of my forked version of TinyUSB.
  • ble-midi2usbhost
  • midi2usbhost
  • midi2usbhub
  • midi2usbhub-web

26-Jul-2023 Updates

• pico-w-ble-midi-lib A MIDI 1.0 Bluetooth LE GATT service server. Used with the following 2 applications.
• pico-w-ble-midi-server-demo A Bluetooth LE MIDI 1.0 server peripheral demo for the Raspberry Pi Pico W. It uses a command line interface to send and recieve Bluetooth LE MIDI data. It also demonstrates using pico-w-ble-midi-lib
• ble-midi2usbhost A Pico W Bluetooth LE MIDI adapter for any class compliant USB MIDI device. With only a few connectors and a power supply you connect any USB MIDI Controller or Synthesizer to a phone, tablet or computer using Bluetooth instead of USB. It also demonstrates using pico-w-ble-midi-lib

8-May-2023 Updates

• pio_midi_uart_lib Add support for using the PIO state machines for MIDI Out only mode.
• midi-multistream2usbdev This new project is designed to give your PC, Mac, etc. a 2 input 6 output USB to 5-pin DIN MIDI interface. It includes files midi_device_multistream.c/h that show how to use the tinyusb library to build a USB MIDI device with more than one virtual MIDI cable per USB endpoint. It also demonstrates using pio_midi_uart_lib in both MIDI UART mode and MIDI Out only mode.

07-Apr-2023 Updates

• pico-usb-host-msc-demo Changed build methods, added code and fixed CMake bugs to allow Pico W builds to coexist with using the Pico-PIO-USB project for the USB Host port
• pico-mc-display-bridge Made the pico_pico_midi_lib submodule project public and fixed other issues such that it should be possible now for people other than me to build the code. Please file an issue if you have any trouble building the code, missing files, etc.
• pico-ssd1306-mono-graphics-lib Now the library will properly claim PIO State Machines so that the PIO units may be shared more easily

25-Mar-2023 Updates

• Fixed the CLI for builds that do not use the DEBUG option. By default, the pico-sdk command line build will not use the DEBUG option. I did not realize that because I use VisualStudio Code IDE for development; the default is the DEBUG option. Without debug, the assert macro was not generating code for the CLI commands, so no commands were being added to the CLI. The symptom is typing help and only seeing the help command as an option. The following projects had this bug and should be fixed.
  • pico-usb-host-msc-demo
  • midi2usbhub-web
  • midi2usbhub-web
  The following projects have this bug and are not fixed yet. I hope to get to it soon. In the meantime, please run cmake with DEBUG enabled (i.e. cmake -DCMAKE_BUILD_TYPE=Debug ..) to build the following projects
  • pico-mc-display-bridge
  • pico-usb-midi-processor
• Updated the tinyusb library version to use with the following projects
  • midi2usbhub-web
  • midi2usbhub-web

MIDI Projects

• pico-w-ble-midi-server-demo A Bluetooth LE MIDI 1.0 server peripheral demo for the Raspberry Pi Pico W.
• ble-midi2usbhost A Pico W Bluetooth LE MIDI adapter for any class compliant USB MIDI device.
• midi2usbhost Add old school MIDI IN and MIDI OUT to a MIDI device with a USB B device port.
• midi2usbdev Create a PC, Mac, etc. MIDI interface with one MIDI IN and one MIDI OUT.
• midi-multistream2usbdev Create a PC, Mac, etc. 2 input 6 output USB to 5-pin DIN MIDI interface. Mac, iOS/iPadOS, and Linux software will show the MIDI port names MIDI IN A, MIDI IN B, MIDI OUT A, MIDI OUT B, ..., MIDI OUT E, MIDI OUT F.
• midi2usbhub Interconnect MIDI devices via a USB hub or old school MIDI. Configure the interconnections using a serial port console and save the configurations as presets in the Pico board's serial flash memory. Back up the presets to USB flash. The USB MIDI host is implemented using the RP2040's native USB hardware.
• midi2piousbhub Interconnect MIDI devices via a USB hub or old school MIDI. Configure the interconnections using a serial port console and save the configurations as presets in the Pico board's serial flash memory. Back up the presets to USB flash. The USB MIDI host is implemented using the RP2040's PIO modules, and the RP2040 native USB port is a USB device port that provides an additional MIDI I/O port (to use a virtual instrument on an iPad, for example), and a USB serial port for the command line interface.
• pico-usb-midi-filter Connect a Raspberry Pi Pico between a USB MIDI device and a USB Host to modify the USB MIDI traffic. The filtering is determined in the source code. The USB descriptor of the attached device is not changed.
• pico-usb-midi-processor Like pico-usb-midi-filter, except it has an OLED display and buttons for configuring what processing to perform, it has up to 8 presets per device, and it allows you to save presets to a USB flash drive.
• midi2usbhub-web. The same as midi2usbhub, except it uses PIO for 2 serial MIDI ports and it adds an embedded webserver UI for configuring routing and an OLED screen+USB keyboard UI for setting up Wi-Fi and recalling presets.
• pico-mc-display-bridge Insert this project between the USB host and any Mackie Control compatible USB MIDI controller to get Mackie Control text display, VPot LED and signal meter for each channel strip, a timecode display, a VPot mode display, some additional per channel strip buttons, and other special function buttons.