The DIY Arduino-based Roland TB303 and TR808 Step Sequencer clone and MIDI Controller. Designed using readily available, inexpensive parts. It can be easily assembled on a protoboard or ordered as PCB. There are two flavors of aciduino:

First version – V1
2 Tracks TB303 sequencer and MIDI Controller.

Second version – V2

Up to 16 Tracks TB303/TR808 sequencer with step, pattern and mute automation grid system, MIDI Controller, OLED display and extensible modular design to plug more potentiometers, buttons, MIDI or CV/Gate interfaces.


303/808 Step Sequencer clone

Programming bass and drum steps using same analogy of original machines • Save your pattern work on microcontroller EPPROM memory for later live gigs • Use step length and shift to make some unusual sequences • Automation grid system for step edit, pattern navigation and mute tracks • Realtime and Step record modes for MIDI keyboard input(v2 only)

Professional grade Clock

Tight and solid clock system using hardware timers to achieve realtime professional grade tick system • Send or receive clock to keep all your external equipment synced

Generative Engine

Generate new and fresh acid music patterns by pressing a single button and twist some parameters • Harmonizer to force musical harmonic modes for bass lines • Euclidian generator for drum parts

Midi Controller

Controls up to 16 parameters per track of your external synthesizers(bass/drums) • Midi learn(v2 only) • 16 potentiometers modular support to extend aciduino as midi controller(v2 only)

Pattern memory

Store your patterns conveniently on the microcontroller’s EEPROM, allowing you to access them effortlessly during live performances.

Easy and fast Assembly

1 hour assembly time on protoboard. Checkout the assembly video of v1:

Looking for v2 assembly steps? click here

Aciduino v2 in action

Aciduino v1 in action

SEQ32: A great extention of v1 built by Conrad Vassallo. You can get schematic and project details on his website.

User galery

Some aciduinos builds around the world: