Mini Tracker

Mini Tracker is the built-in music tracker for composing music compatible with the Mega Drive's sound hardware and the XGM2 sound driver. It provides a traditional tracker-style interface with full access to the YM2612 FM synthesizer, SN76489 PSG, and DAC sample playback.

Features

• 13-channel editing — 6 FM channels, 3 FM3-extended operator channels, 3 PSG square channels, and 1 noise channel.
• FM instrument editor — Full 4-operator FM synthesis with algorithm, feedback, ADSR envelopes, and 11 built-in presets.
• PSG instrument editor — 16-step volume envelopes and arpeggio sequences with 4 presets.
• DAC sample editor — Load, edit, and loop audio samples (WAV, MP3, OGG, FLAC, AIFF) for playback on FM channel 6.
• Pattern-based sequencing — Up to 256 patterns with configurable row count (1–256), reusable via references or deep copies.
• 22+ effects — Standard tracker effects (arpeggio, portamento, vibrato, volume slide) plus FM-specific effects for real-time operator control.
• FM3 extended mode — Per-operator frequency control for FM channel 3, enabling complex multi-voice patches.
• Import/export — Import from VGM, MIDI, DefleMask (.dmf), and Furnace (.fur). Export to VGM and MIDI.
• MIDI input — Connect a MIDI keyboard for real-time note entry.
• Undo/redo — Full history support for all operations.

Interface Overview

Toolbar

The toolbar spans two rows at the top of the editor:

• File operations — New, Save, Load, Import (VGM, MIDI, DMF, Furnace), Export (VGM, MIDI).
• Transport controls — Play from cursor (F5), Play from start (F6), Stop (F8).
• Song parameters — BPM (60–300), Speed (1–31 ticks per row), Rows per pattern (1–256), Octave (0–9), Edit step (0–16).
• FX columns — Number of visible effect columns per channel (1–8).
• CH3 mode — Toggle between Normal, Extended, and CSM modes.
• Master volume — Adjustable from 0% to 200%.

Order List

The left panel shows the song's pattern sequence. Each entry maps an order position to a pattern number.

• Add (+) — Append a new empty pattern.
• Remove (-) — Remove the selected order entry (pattern data is preserved).
• Duplicate (Dup) — Create an independent copy of the pattern.
• Reference (Ref) — Reuse the same pattern data (edits affect all references). A badge shows the reference count.
• Up / Down — Reorder entries in the sequence.

Pattern Editor

The central area displays the pattern grid. Each row contains cells for every channel, and each cell has columns for Note, Instrument, Volume, and up to 8 effect slots.

• Color-coded channels — FM (blue), PSG (green), DAC (orange), Noise (purple).
• Edit mode — Press Space to toggle. The cursor border turns red when edit mode is active.
• Layout modes — Vertical (default, channels side by side) or Horizontal (channels stacked).

Instrument Editor

The bottom panel has four tabs:

• FM — Algorithm/feedback selector, 4 operator panels with full ADSR and parameter controls, 11 presets.
• PSG — 16-step volume envelope editor and arpeggio sequence, 4 presets.
• DAC — Waveform viewer with loop markers, normalize/reverse tools, sample rate display.
• Piano — Interactive keyboard for previewing instruments.

Channels

Mini Tracker provides 13 channels that map to the Mega Drive's sound hardware:

Channel	Chip	Description
FM1–FM6	YM2612	6 FM synthesis channels. FM6 doubles as the DAC output for sample playback.
3-OP1–3-OP3	YM2612	FM3's individual operators when CH3 Extended mode is enabled.
SQ1–SQ3	SN76489	3 PSG square wave channels.
NOI	SN76489	1 noise channel (white or periodic noise).

CH3 Modes

FM channel 3 supports three modes:

• Normal — Standard FM channel, all 4 operators share one frequency.
• Extended — Each operator can have an independent frequency via the 3-OP channels, enabling multi-voice patches from a single channel.
• CSM — Carrier Suppress Modulation mode for special synthesis effects.

FM Instruments

FM instruments use 4-operator frequency modulation synthesis. The algorithm (0–7) determines how the operators are routed (series, parallel, or mixed), and the feedback (0–7) controls self-modulation on operator 1.

Each operator has:

Parameter	Range	Description
Detune (DT)	0–7	Fine frequency offset
Multiplier (MUL)	0–15	Frequency multiplier
Total Level (TL)	0–127	Output level (0 = loudest)
Rate Scaling (RS)	0–3	Key-dependent envelope speed
Attack Rate (AR)	0–31	Attack speed
Decay 1 Rate (D1R)	0–31	First decay speed
Decay 2 Rate (D2R)	0–31	Sustain/second decay speed
Release Rate (RR)	0–15	Release speed
Sustain Level (SL)	0–15	Level at which D1R transitions to D2R
AM Enable	On/Off	Amplitude modulation by LFO
SSG-EG	0–15	SSG envelope generator mode

Additional per-channel parameters:

• AMS (0–3) — Amplitude modulation sensitivity.
• FMS (0–7) — Frequency modulation sensitivity.

FM Presets

11 built-in presets: Default, Piano, Bass, Organ, Guitar, Strings, Brass, Synth Lead, Synth Pad, Chroma Perc, Reed.

PSG Instruments

PSG instruments define how the SN76489's square wave channels shape their sound:

• Volume envelope — A 16-step sequence controlling attenuation over time (0 = loudest, 15 = silent).
• Arpeggio sequence — Optional semitone offsets applied per tick for rapid pitch changes.

PSG Presets

4 built-in presets: Default, Staccato (quick decay), Soft (slow attack), Pluck (fast attack and decay).

DAC Samples

FM channel 6 can play back 8-bit PCM samples instead of FM synthesis. The DAC editor supports:

• Loading samples from WAV, MP3, OGG, FLAC, and AIFF files.
• Waveform display with zoom and scroll.
• Loop start/end markers for looping samples.
• Normalize and reverse processing.

Effects

Effects are entered as a type byte followed by a value byte (e.g., 01 40 = portamento up at speed 64). Each cell can have up to 8 effect slots.

Standard Effects

Code	Effect	Value
00	Arpeggio	xy — Alternates between note, note+x, note+y semitones
01	Portamento up	xx — Pitch slide speed
02	Portamento down	xx — Pitch slide speed
03	Tone portamento	xx — Slide to target note at speed
04	Vibrato	xy — x = speed, y = depth
07	Tremolo	xy — x = speed, y = depth
08	Set panning	xx — <40 = left, 40–BF = center, >=C0 = right
09	Note retrigger	xx — Retrigger interval in ticks
0A	Volume slide	xy — x = slide up, y = slide down
0B	Jump to order	xx — Order position
0C	Set volume	xx — Volume (0–127)
0D	Pattern break	xx — Row in next pattern
0E	Extended	Cx = note cut after x ticks, Dx = note delay by x ticks
0F	Set speed/BPM	xx — Below 20 = speed (ticks/row), 20+ = BPM

FM-Specific Effects

Code	Effect	Value
10	Set algorithm	00–07
11	Set feedback	00–07
12	Set multiplier	Bits 7–6 = operator, bits 3–0 = value (0–15)
13	Set detune	Bits 7–6 = operator, bits 2–0 = value (0–7)
14	Set attack rate	Bits 7–6 = operator, bits 4–0 = value (0–31)
15	Set D1R	Bits 7–6 = operator, bits 4–0 = value (0–31)
16	Set D2R	Bits 7–6 = operator, bits 4–0 = value (0–31)
17	Set total level	Bits 7–6 = operator, bits 5–0 = value (0–63)
18	Set release rate	Bits 7–6 = operator, bits 3–0 = value (0–15)
19	Set sustain level	Bits 7–6 = operator, bits 3–0 = value (0–15)
1A	Set SSG-EG	Bits 7–6 = operator, bits 3–0 = value (0–15)
1B	Set AMS/FMS	xy — x = AMS (0–3), y = FMS (0–7)

PSG-Specific Effects

Code	Effect	Value
1C	Noise mode	Bit 2 = white (1) / periodic (0), bits 1–0 = frequency

Global Effects

Code	Effect	Value
20	LFO frequency	00–07
21	Timer A	High byte control
22	CSM toggle	01 = on, 00 = off

File Format

Mini Tracker uses the .mtrk file format — gzip-compressed JSON with embedded DAC sample data as base64.

Import Formats

• VGM (.vgm) — Experimental, reverse-engineers register writes into patterns.
• MIDI (.mid) — Converts note events to tracker patterns.
• DefleMask (.dmf) — Full tracker data import.
• Furnace (.fur) — Full tracker data import.
• Instruments — TFI, TYI, Y12, OPM, DMP files can be imported into the instrument editor.

Export Formats

• VGM (.vgm) — Full register log for hardware-accurate playback.
• MIDI (.mid) — Note and timing data export.

Keyboard Shortcuts

Playback

Shortcut	Action
F5	Play from cursor
F6	Play from start
F8	Stop
Space	Toggle edit mode

File

Shortcut	Action
Ctrl+S	Save
Ctrl+O	Load
Ctrl+Z	Undo
Ctrl+Y	Redo

Navigation

Shortcut	Action
Arrow keys	Move cursor
Tab / Shift+Tab	Next / previous channel
PageDown / PageUp	Jump 16 rows
Home / End	First / last row
Ctrl+Up / Ctrl+Down	Jump by beat

Editing

Shortcut	Action
Delete	Clear cell
Insert	Insert row
Shift+Delete	Delete row
Ctrl+C / Ctrl+X / Ctrl+V	Copy / Cut / Paste
Ctrl+A	Select all (progressive: cell, channel, all)
Ctrl+Delete	Clear column
Ctrl+Backspace	Clear channel
[ / ]	Decrease / increase edit step

Transpose

Shortcut	Action
Ctrl+F1	Transpose down 1 semitone
Ctrl+F2	Transpose up 1 semitone
Ctrl+F3	Transpose down 1 octave
Ctrl+F4	Transpose up 1 octave

Channel

Shortcut	Action
F9	Mute/unmute channel
F10	Solo channel

Note Input (Edit Mode)

Notes are entered using a piano-style keyboard layout:

• Lower octave — Z X C V B N M (C D E F G A B), sharps on S D G H J.
• Upper octave — Q W E R T Y U I O P (C D E F G A B C D E), sharps on 2 3 5 6 7 9 0.
• Note off — 1 in the note column.
• Hex values — 0–9, A–F for instrument, volume, and effect columns.