Reflex Adapt Classic2USB

Classic2USB is the unified RP2040 firmware for Reflex Adapt classic-controller USB adapters. Every supported input and output mode fits in one firmware image, so changing controllers or hosts no longer requires reflashing the adapter.

For setup, see the Classic2USB Quick Start. For complete behavior and compatibility details, see the Classic2USB Manual and Input Reference.

Reflex Adapt hardware is available from the Reflex Adapt product page. Compatible controller cables and breakouts are listed with the HDMI controller adapters. Looking for the original Reflex Adapt Firmware? Check here.

1. One universal firmware - all Classic2USB input modes, USB output modes, settings, and utilities are available in one UF2 image.
2. Ultra low latency - many digital-controller modes measure below 1 ms mean latency with 1 ms USB polling.
3. Automatic controller detection - Auto input recognizes most supported controller families, while the rest use clear on-screen assisted detection prompts.
4. Automatic host detection - Auto output identifies supported Windows and console hosts. Generic USB hosts without a positive Windows or console signature, including MiSTer and typical Linux systems, use the saved MiSTer/Linux output preference.
5. On-device configuration - the OLED menu exposes controller, output, display, hotkey, rumble, analog, and system settings without requiring a PC.
6. Per-button customization - configure turbo and remapping per button, with configurable Home, Capture, Quick Menu, and System Menu hotkeys.
7. Two-player features - native two-port operation where supported, two-player DInput and XInput PC output, plus 2P Merge for combining both physical inputs into one virtual controller for wacky fun.
8. Memory-card and accessory tools - access Dreamcast VMUs, PlayStation Memory Cards, N64 Controller Paks, and N64 Transfer Pak GB/GBC ROM and save data through the serial management interface, including full-card and individual-save backup and restore.
9. MiSTer integration - reflex_adapt_manager.sh installs firmware, rollbacks, and required mappings for Classic2USB and Adapt V1 / Legacy from one menu.

Quick Settings contains the controls relevant to the active controller family. For example, PSX mode exposes input/output selection, rumble, turbo, and button remapping:

System Settings contains global Windows and MiSTer/Linux Auto-output preferences, display contrast, home-screen, Kiosk Mode, hotkey, sound, and other device settings:

Rumble defaults to Variable whenever the connected controller supports proportional strength. Variable preserves the strength requested by the host; Max converts each nonzero motor command to full strength while keeping separate motor channels independent. DualShock and DualShock 2 pads and SNES RumbleTech support variable strength. N64 Rumble Paks and wired GameCube controllers are binary devices, so their menu is simply Off/On. Rumble controls are hidden for controllers without supported feedback, such as digital PSX pads, JogCon, WaveBird, and currently Dreamcast controllers.

Open the System Settings menu recording.

Reflex Kiosk Mode is available under Kiosk in System Settings and is off by default. Selecting it opens an On / Off / Cancel confirmation. Enabling it prevents accidental front-button actions: opening Quick Settings or rebooting requires two quick taps instead of one. The 3-second holds still open System Settings and start Auto input detection, and holding Reset while connecting USB still enters the bootloader.

Measured results are end-to-end using MiSTer in DInput mode, the NES latency-test core, an external Arduino fixture, and 1 ms USB polling. Complete sample counts, minimums, maximums, and methodology are documented in the Classic2USB Manual.

With Auto output selected, Windows Mode and MiSTer Mode independently choose DInput, XInput, or Keyboard. Both default to DInput. Windows XInput uses the four-child receiver personality; MiSTer/Linux XInput uses two wired interfaces and requires no MiSTer kernel changes. MiSTer Mode is the generic-host fallback: it is used when detection does not find a positive Windows or console signature, which includes MiSTer and typical Linux hosts but can also include other generic USB hosts. DInput remains recommended because it keeps WebHID, serial management, the utility drive, and MiSTer-specific paths available.

MiSTer also has specialized GunCon, JogCon, and neGcon paths. Most standard controller modes work through MiSTer's GameControllerDB; N64, PlayStation, Saturn, and Jaguar layouts use dedicated .map files where the generic mapping format cannot express the complete controller.

Classic2USB is the release PlatformIO environment:

pio run -e classic2usb -t uf2

The UF2 is exported to dist/classic2usb.uf2.

Build the complete release package with firmware, documentation, MiSTer files, and artifact hashes:

python tools/package_release.py --target classic2usb

The package is written to dist/classic2usb_package.

MiSTer uses one Downloader database and one reflex_adapt_manager.sh entry point for supported Adapt products. The manager detects connected hardware and offers only applicable firmware, rollback, settings, and mapping actions.

Classic2USB's DInput utility drive includes ADAPTDL.INI as a small Downloader bootstrap. You can also install tools/adapt_manager/reflex-adapt-manager.ini with MiSTer Downloader or copy the packaged mister/ directory to /media/fat/.

Adapt V1 / Legacy firmware remains in the separate Reflex-Adapt-Legacy archive. Reflex Adapt Manager downloads those exact published binaries rather than duplicating them here. Future Adapt products can extend the same manager catalog instead of introducing separate update tools.

Classic2USB follows semantic versioning. Firmware version constants live in firmware/firmware_build_info.h, and stable release tags use vX.Y.Z.

• MAJOR: incompatible USB, serial, settings, manager, or package contract
• MINOR: backward-compatible features, modes, or supported hardware
• PATCH: compatible fixes for behavior, timing, mappings, packaging, or docs

The version identifies the firmware target rather than a PCB revision. One Classic2USB release supports every published Classic2USB RP2040 2 MB hardware revision unless its release notes explicitly state otherwise.

Reflex Adapt firmware is GPL-3.0-or-later unless a file states otherwise. See LICENSE, docs/NOTICE.md, and third_party/licenses for attribution and upstream license copies.