Teensy MIDI looper

I built a simple MIDI looper with the Teensy 3.2 development board

It's a simple device. It has two MIDI inputs, one serving as a THRU port, mostly for forwarding sync messages to the connected device. The other input port is for connecting the instrument. The output port binds the loop for sending and receiving notes.

The first version soldered to a stripboard. The left and center MIDI connectors are the inputs connected to the Teensy (header pins visible) through an optocoupler circuit

Teensy is the perfect fit for this kind of project, mostly due to its tiny dimensions. It works with the same development setup as Arduino, and virtually all libraries that work with Arduino work with Teensy. It even includes a MIDI library, which came in handy. The code is trivial; the gist is that we read the input tempo, start and stop messages from the THRU port and merge the tempo message with incoming note data. The note data quantizes to the nearest 8th sync message.

Up to date feature list and basic build instructions found from the repo

https://github.com/jjylik/teensy-midi-looper

Comments

I'm not a passionate developer

A family friend of mine is an airlane pilot. A dream job for most, right? As a child, I certainly thought so. Now that I can have grown-up talks with him, I have discovered a more accurate description of his profession. He says that the truth about the job is that it is boring. To me, that is not that surprising. Airplanes are cool and all, but when you are in the middle of the Atlantic sitting next to the colleague you have been talking to past five years, how stimulating can that be? When he says the job is boring, it is not a bad kind of boring. It is a very specific boring. The "boring" you would want as a passenger. Uneventful. Yet, he loves his job. According to him, an experienced pilot is most pleased when each and every tiny thing in the flight plan - goes according to plan. Passengers in the cabin of an expert pilot sit in the comfort of not even noticing who is flying. As someone employed in a field where being boring is not exactly in high demand, this sounds pro...

Canyon Precede:ON 7

I bought or technically leased a Canyon Precede:ON 7 (2022) electric bike last fall. This post is about my experiences with it after riding for about 2000 km this winter. The season was a bit colder than usual, and we had more snow than in years, so I properly put the bike through its paces. I've been cycling for almost 20 years. I've never owned a car nor used public transport regularly. I pedal all distances below 30km in all seasons. Besides commuting, I've mountain biked and raced BMX, and I still actively ride my road bike during the spring and summer months. I've owned a handful of bikes and kept them until their frames failed. Buying new bikes or gear has not been a major part of my hobby, and frankly, I'm quite sceptical about the benefits of updating bikes or gear frequently. I've never owned an E-bike before, but I've rented one a couple of times. The bike arrived in a hilariously large box. I suppose there's no need to worry about damage durin...

Emit structured Postgres data change events with wal2json

A common thing I see in an enterprise system is that when an end-user does some action, say add a user, the underlying web of subsystems adds the user to multiple databases in separate transactions. Each of these transactions may happen in varying order and, even worse, can fail, leaving the system in an inconsistent state. A better way could be to write the user data to some main database and then other subsystems like search indexes, pull/push the data to other interested parties, thus eliminating the need for multiple end-user originating boundary transactions. That's the theory part; how about a technical solution. The idea of this post came from the koodia pinnan alla podcast about event-driven systems and CDC . One of the discussion topics in the show is emitting events from Postgres transaction logs. I built an utterly simple change emitter and reader using Postgres with the wal2json transaction decoding plugin and a custom go event parser. I'll stick to the boring ...

Koodihommia

Search This Blog