padbound 0.2.0

A stateful python interface for USB MIDI controllers.

A general, stateful python interface for MIDI controllers that abstracts hardware differences behind a simple API.

Overview

Padbound provides a high-level abstraction over MIDI controllers, allowing applications to work with three fundamental control types (toggles, momentary triggers, continuous controls) and RGB colors without dealing with raw MIDI messages.

Features

• Three Control Types: Toggle, Momentary, and Continuous controls with unified API
• Progressive State Discovery: Honest representation of hardware limitations (knobs/faders start in "unknown" state)
• Capability-Based API: Validates hardware support before attempting operations
• Thread-Safe: Safe concurrent access from callbacks and main thread
• Plugin Architecture: Extensible system for supporting different controllers
• Callback System: Global, per-control, and type-based callbacks with error isolation
• Bank Support: Handles controllers with bank switching (when supported)
• Strict/Permissive Modes: Choose between errors or warnings for unsupported operations

Installation

pip install padbound

Quick Start

from padbound import Controller, ControlType

# Auto-detect and connect to controller
with Controller(plugin='auto', auto_connect=True) as controller:
    # Register callback for a specific pad
    controller.on_control('pad_1', lambda state: print(f"Pad 1: {state.is_on}"))

    # Register callback for all continuous controls (knobs/faders)
    def on_continuous(control_id, state):
        if state.is_discovered:
            print(f"{control_id}: {state.normalized_value:.2f}")
    controller.on_type(ControlType.CONTINUOUS, on_continuous)

    # Main loop
    while True:
        controller.process_events()

Examples

See the examples/ directory for controller-specific demos:

• demo_akai_lpd8.py - AKAI LPD8 MK2
• demo_akai_apc_mini_mk2.py - AKAI APC mini MK2
• demo_presonus_atom.py - PreSonus ATOM
• demo_xjam.py - Xjam
• demo_x_touch_mini.py - Behringer X-Touch Mini

Callback Registration

from padbound import Controller, ControlType

with Controller(plugin='auto', auto_connect=True) as controller:
    # Per-control callback
    controller.on_control('pad_1', lambda state: print(f"Pad 1: {state.is_on}"))

    # Per-type callback (all toggles, all continuous, etc.)
    controller.on_type(ControlType.TOGGLE, lambda cid, state: print(f"{cid} toggled"))

    # Per-category callback (e.g., all transport buttons)
    controller.on_category('transport', lambda cid, state: print(f"Transport: {cid}"))

    # Global callback (all controls)
    controller.on_global(lambda cid, state: print(f"Any control: {cid}"))

    while True:
        controller.process_events()

Setting Control State

from padbound import Controller

with Controller(plugin='auto', auto_connect=True) as controller:
    # Set pad LED color and state
    if controller.can_set_state('pad_1', is_on=True, color='red'):
        controller.set_state('pad_1', is_on=True, color='red')

    # Query control state
    state = controller.get_state('pad_1')
    if state:
        print(f"Pad 1 is {'on' if state.is_on else 'off'}")

Using Configuration

from padbound import Controller, ControllerConfig, BankConfig, ControlConfig, ControlType

# Configure pad colors and types
config = ControllerConfig(banks={
    'bank_1': BankConfig(controls={
        'pad_1': ControlConfig(type=ControlType.TOGGLE, color='red', off_color='dim_red'),
        'pad_2': ControlConfig(type=ControlType.MOMENTARY, color='green'),
    })
})

with Controller(plugin='auto', config=config, auto_connect=True) as controller:
    while True:
        controller.process_events()

Supported Controllers

Capability Comparison

Controller	Pads	Knobs/Encoders	Faders	Buttons	RGB LEDs	LED Modes	Banks	Persistent Config	Special Features
AKAI LPD8 MK2	8	8 knobs	—	—	✓ Full	Solid	4 (HW)	✓ SysEx	Multi-signal pads (NOTE/CC/PC)
AKAI APC mini MK2	64	—	9	17	✓ Full	Solid/Pulse/Blink	1	—	Fader position discovery
PreSonus ATOM	16	4	—	20	✓ Full	Solid/Pulse/Blink	8 (HW)	—	Native Control mode, encoder acceleration
Xjam	16	6	—	—	—	—	3 (HW)	✓ SysEx	Multi-signal pads, multiple encoder modes
X-Touch Mini	16	8 + buttons	1	—	Single	Solid	2 (HW)	—	Deferred LED feedback, auto-reflecting encoder rings

Legend:

• HW = Hardware-managed bank switching
• RGB LEDs: Full = True RGB color support, Single = On/off only
• LED Modes: Animation/behavior modes supported
• Persistent Config: Device stores configuration in non-volatile memory

Detailed Controller Information

AKAI LPD8 MK2

Control Surface: 8 RGB pads + 8 knobs
Banks: 4 banks with hardware-based switching
Capabilities:

• Pad LED Feedback: Full RGB via SysEx
• Pad LED Modes: Solid
• Pad Modes: Toggle or momentary (global per bank)
• Knob Feedback: None (read-only)
• Configuration: Persistent (SysEx)

AKAI APC mini MK2

Control Surface: 8×8 RGB pad grid + 9 faders + 17 buttons
Banks: Single layer
Capabilities:

• Pad LED Feedback: Full RGB via SysEx
• Pad LED Modes: Solid, pulse, blink
• Pad Modes: Toggle or momentary (per pad)
• Fader Feedback: None (read-only, initial position discovered)
• Button LED Feedback: Single-color (red for track, green for scene)
• Configuration: Volatile

PreSonus ATOM

Control Surface: 16 RGB pads (4×4) + 4 encoders + 20 buttons
Banks: 8 hardware-managed banks (not software-accessible)
Capabilities:

• Pad LED Feedback: Full RGB via Native Control mode
• Pad LED Modes: Solid, pulse, breathe
• Pad Modes: Toggle or momentary (per pad)
• Encoder Type: Relative with acceleration
• Encoder Feedback: None (read-only)
• Button LED Feedback: Single-color
• Configuration: Volatile

Xjam (ESI/Artesia Pro)

Control Surface: 16 pads + 6 knobs per bank
Banks: 3 banks (Green, Yellow, Red) with synchronized pad/knob switching
Capabilities:

• Pad LED Feedback: None (hardware-managed)
• Pad Modes: Toggle or momentary (global)
• Knob Type: Configurable (absolute or 3 relative modes)
• Knob Feedback: None (read-only)
• Configuration: Persistent (SysEx)

Behringer X-Touch Mini

Control Surface: 8 encoders with buttons + 16 pads + 1 fader
Banks: 2 layers (A, B) with hardware switching
Capabilities:

• Pad LED Feedback: Single-color
• Pad LED Modes: Solid
• Pad Modes: Toggle or momentary (per pad)
• Encoder Type: Absolute
• Encoder Feedback: LED ring auto-reflects value
• Encoder Button Feedback: Single-color
• Fader Feedback: None (read-only)
• Configuration: Volatile

Documentation

TBD

Acknowledgements

Some protocol information for supported controllers was gathered from:

• AKAI LPD8 MK2: stephensrmmartin/lpd8mk2
• PreSonus ATOM: EMATech/AtomCtrl
• Behringer X-Touch Mini: AndreasPantle/X-Touch-Mini-HandsOn

License

MIT License