Bar LED for Elektron Octatrack

The tempo LED flashes green on the pattern's 1 while the sequencer plays; every other beat stays red.

Module version 0.1.0-experimental. Base firmware: 1.40C.

About this module

A visual downbeat for players who can't use the click track, for example when the cue outputs feed external effects. While the sequencer plays, the tempo LED flashes green on the first beat of each pass of the pattern and red on every other beat, as stock does. It reads the sequencer's own step, so it follows the pattern length. Stopped, it is stock. Nothing to set: install it and press PLAY.

• Green on the pattern's 1, stock red on every other beat.
• Reads the sequencer's master step: the green follows the pattern's length.
• No menu, no knob, no project data: remove the module and the LED is stock again.

How to use it

1. Press [PLAY]: the first flash is green, then red until the pattern comes round again.
2. Set the pattern's length (FUNC + PAGE, PATTERN SCALE) to 12 or 20 steps: the green still lands on the pattern's first step.
3. Press [STOP]: the LED behaves as stock, and the next [PLAY] starts green again.

Compatibility notes

• OS 1.40C. The tempo LED only flashes on whole beats: when the pattern's 1 falls mid-beat (say 14 steps at 1x), the green comes on the first flash after it.
• Green is LED id 39, the pair of stock's red 38; seen green on an MKI over USB, MKII not tested.
• A pattern change while playing is checked in the emulator only; not yet tested on a unit.

Test evidence

Reported by the tester on an MKI over USB on the Modwerk beta base 9680e9ac with the committed package de7f9cae (5 November 2026, beside Slow LFO): SELF TEST passed, 2/2 intact, longest frame 371 us; green on the pattern's 1 on external MIDI clock, through tempo changes while playing, at pattern scales 3/4, 3/2 and 2X, on the master length in per-track mode, and after continuing from a pause. Earlier builds: a native card build (2 November) and package bce3b4d6 over USB (4 November, trial, Keep, power cycle, removal). ot_emu on stock 1.40C (verify.py): every beat flash on master step 0 asks for id 39 and every other for stock's 38 at 12, 16 and 20 steps, through two pauses, and across a switch to a pattern of another length at the loop point.