Understanding USB MIDI: an introduction

You plug your USB MIDI Keyboard into your computer and it (mostly) just works. Do you ever wonder how? Do you wish you could plug your USB keyboard to your
synth, but it doesn't have a regular MIDI OUT? This is the workshop for you!

This talk will show how USB MIDI works, with an intro section so you know how USB works in general. It describes MIDI 1.0 on Full Speed USB 2.0 only because that is what is most commonly used by most USB MIDI hardware these days. By the end of the talk, you should have a better idea what goes on when you plug your MIDI controller to a computer and how MIDI data is communicated.

You will learn about free software tools and low cost hardware for deep debugging of USB MIDI devices and for solving common problems with USB MIDI (and Audio). The talk will conclude with demonstrations of some USB MIDI host and device projects with links to more details on GitHub.

This free workshop is a lecture only; No DIY projects will be built or provided during the lecture.

Outline:
Part I: Enough USB background to fake it
A Description of USB hardware
- USB versions and speeds
- USB Power
- USB connectors
- Plug in and unplug detection
- USB data signaling
A look at USB roles
- The USB host
- The USB device
- The USB hub
USB Endpoints - the pipes that move data
- Control
- Interrupt
- Bulk
- Isochronous
USB Descriptors: how the host knows what you plugged in
- The Device Descriptor
- The Configuration Descriptor
- The Endpoint Descriptor

Part II: USB MIDI
- USB MIDI Data packets
- USB MIDI Descriptors
- USB MIDI Devices
- USB MIDI Hosts

Part III: Using this information day to day
- Why doesn't the computer recognize my USB MIDI controller when I plugged it in?
- Why am I getting stuck notes?
- Why does my controller keep resetting?

Part IV: Rolling your own on the Raspberry PI Pico board
- Demo 1: USB MIDI device to DIN MIDI converter
- Demo 2: USB MIDI host to DIN MIDI converter for DAWless operation with USB MIDI Devices
- Demo 3: A USB MIDI processor
- Demo 4: A USB MIDI routing hub

Instructors:
Paul Kovitz

Date: Sunday, January 25th, 2026
Time: 1 PM to 3 PM
Location: Synth Library Portland
1256 Lloyd Center
Lloyd Center Mall, 2nd Floor, near Dicepool

RSVP Required ($5 Suggested Donation)
(We always encourage donations or becoming a member if you want to support our mission of bringing low-cost/no-cost creative tools and education to our local community)