Bridge keyboards and mice with classic hardware!

Connect modern USB keyboards and mice to a classic ADB-based Macintosh, Apple IIgs, or NeXT

Connect legacy ADB input hardware to a USB-based computer running Windows, OSX, or Linux The Wombat is a bidirectional ADB-to-USB and USB-to-ADB converter for keyboards and mice. No special software or drivers are needed – just plug it in and go. Now you can finally use a modern optical mouse with your vintage Macintosh, or amuse your coworkers with a retro ADB keyboard on your work machine. ADB-USB Wombat is an indispensable tool for Apple collectors and enthusiasts.





Hardware shipments may be slower than normal due to COVID-19 delays. Please be patient.

ADB-USB Wombat comes fully assembled and tested. ADB-USB Wombat Input Converter, $49

A bidirectional USB-to-ADB and ADB-to-USB converter. This is the Wombat main board. Optional ADB and USB cables may be purchased separately. More Info Add to Cart Optional accessories for your Wombat: Optional accessories for your Wombat: Black Acrylic Case for ADB-USB Wombat, $10

A glossy acrylic cover to protect and showcase your Wombat board. This is a plate style case with open sides and a logo-etched top. Requires assembly More Info Add to Cart ADB cable 3 ft, $5

For connecting the Wombat to an ADB-based Macintosh, Apple IIgs, or NeXT computer. Standard male-to-male S-video cables from eBay work too. More Info Add to Cart Find more items in the BMOW store



ADB-USB Wombat is great for breathing new life into your vintage Apple hardware collection. If you love old Macs, you know ADB keyboards are expensive and hard to find, and ADB mice are sticky and trouble-prone. With the Wombat, you can substitute modern USB input peripherals instead. Or if you swear by your old Apple Extended Keyboard, you can use it with your modern computer. Visitors are sure to smile when they see you running 1980s Apple input peripherals on your 2017 machine.

No external power source needed

On-board power key for remote turn-on

Upgradable firmware

Works with your favorite mice and keyboards

The Wombat was developed by Steve Chamberlin, here at Big Mess o’ Wires. See the blog archive for technical details on its software and hardware.



Compatibility

The Wombat hardware is compatible with all Apple computers, keyboards, and mice using a mini DIN 4-pin ADB connector, including most early Macintosh computers, the Apple IIgs, and some NeXT computer models. It is also compatible with standard USB keyboards and mice with a USB-A connector. When in ADB-to-USB conversion mode, it works under Windows, OSX, Linux, Chrome OS, or any other operating system that supports USB HID input peripherals.

Security dongles, joysticks, and other less common devices are not supported.



USB to ADB

Connect USB keyboards and mice to a classic ADB-based Macintosh, Apple IIgs, or NeXT computer. Set the Wombat board’s jumpers to USB input mode, as shown on the diagram. Power will be supplied from the computer. Use an ADB cable to connect the board’s ADB port to the computer’s ADB port.

A single USB peripheral can be connected directly to the Wombat board’s USB-A port at CON1, or a standard USB hub can be used to connect multiple peripherals at once. When in this mode, the Wombat supports one USB keyboard and one USB mouse, as well as any number of ADB keyboards and mice, all used simultaneously.

Standard bus-powered USB hubs are recommended. Some externally powered USB hubs (with their own independent power supply) can backfeed power into the Wombat even when it’s off, causing problems.

Right Click Behavior – Most ADB mice had only one button, so the USB mouse’s right button is handled one of two ways. Macintosh mode sends a control + click event to the host, which opens context menus in Mac OS 8 and later. NeXT mode sends a true right click event to the host. The default is Macintosh control + click mode. Toggle between the two modes by clicking the USB mouse wheel button (button 3).

Mouse Wheel Behavior – ADB mice did not have a mouse wheel. USB mouse wheel movements will send up/down arrow key events to the host. This works well for document scrolling and file dialogs. If necessary, this “mouse wheel arrow keys” behavior can be disabled using the custom key mapping tool, described below.



ADB Power Key

Power Key – Original ADB keyboards had a power key – a square or rectangular key with a triangle logo that could be used to turn on some later models of ADB Macintosh computers. There’s an equivalent button on the Wombat board that will function as a substitute power key, even when the computer is off.



Connections for Standby Power

Standby Power – When the Wombat is powered from an auxiliary source, it can continue working even when the computer is off. In this case, the PRINT SCREEN key or F13 key on a USB keyboard will also function as the power key to turn on the computer. To provide standby power, set the board’s jumpers to USB+PWR mode, as shown on the diagram (board version 1.1 or later only). Connect a standard USB charger to the board’s USB-B port at CON2.



ADB to USB

Connect ADB keyboards and mice to a modern USB-based computer. Set the Wombat board’s jumpers to ADB input mode, as shown on the diagram. Power will be supplied from the computer. Use a USB-A to USB-Mini-B cable to connect the board’s USB-B port at CON2 to the computer’s USB port. This is the same cable commonly used to connect mobile phones and other devices to a computer. In this mode, nothing should be connected to the Wombat board’s USB-A port at CON1.

A single ADB peripheral can be connected directly to the Wombat board’s ADB port, or multiple peripherals can be daisy-chained, using the ADB pass-through connector found on all Apple ADB keyboards. When in this mode, the Wombat supports one ADB keyboard and one ADB mouse, as well as any number of USB keyboards and mice, all used simultaneously.

The ADB peripherals will appear as standard HID input devices to modern Windows, OSX, and Linux computers. No special drivers or other software are needed.



Firmware Updates

The Wombat firmware can be updated to fix bugs and add new features. Download the firmware.hex file from the downloads section below, and copy the file to a USB flash drive.

During the firmware update process, the Wombat board can be powered from an ADB-based computer and ADB cable attached at CON3, or from a standard USB charger and USB-B cable attached at CON2. If powering from an ADB cable, set the board’s jumpers to select USB-to-ADB mode. If powering from a USB-B cable, set the board’s jumpers to Standby Power mode (USB+PWR).

Disconnect all power from the Wombat board. Plug the flash drive directly into the board’s USB-A port CON1 – do not use a hub. Hold the board’s power key button while you connect the power source to turn on the board. Continue to hold the button for a few seconds, until the A and B status LEDs begin blinking rapidly. The update process takes about 10 seconds. When finished, the LEDs will blink slowly together, once per second.

LED Status Codes

The A and B LEDs on the Wombat board display status and error information. (The A LED is labeled RUN on some boards). During normal use, the A LED will turn on when the Wombat has a working data connection (ADB or USB) to the host computer. The B LED will blink whenever there’s keyboard or mouse activity.

During a firmware update, both LEDs are used to indicate update status:

slow alternating blinks of A, then B (1 blink/sec) – bootloader is searching for a firmware file

fast alternating blinks of A, then B (8 blinks/sec) – bootloader is updating the firmware

slow synchronized blinks of A and B together (1 blink/sec) – bootloader finished successfully

If B blinks several times while A remains off, it indicates a bootloader error:

2 blinks – no valid firmware exists on chip, can’t start main Wombat program

3 blinks – no firmware files found on USB drive

4 blinks – error in firmware file (checksum mismatch or illegal data)

5 blinks – error while updating firmware in chip memory



Help Commands

You can interact directly with the Wombat by typing help commands on an attached ADB or USB keyboard. Open an empty text document or command prompt on your computer. The Wombat will “type” its responses to your commands, so they appear on the screen.

Control-Shift-Capslock-T – Cycles between key mapping types US-GENERIC (ANSI QWERTY), ISO-GENERIC (UK and other non-US QWERTY), ISO-FR (AZERTY), and ISO-DE (QWERTZ)

Control-Shift-Capslock-G – Shows the currently active key mapping type

Control-Shift-Capslock-V – Displays the firmware version number

Control-Shift-Capslock-I – Displays the USB vendor and product ID or ADB handler ID of the keyboard and mouse

Control-Shift-Capslock-C – Enters keydump mode. While in this mode, the USB key code is displayed for each key that you press, along with the corresponding ADB key code it’s mapped to (or vice-versa). This can be helpful for troubleshooting key mapping problems.

Control-D – Exits keydump mode.



International Keyboards

Non-US international keyboards are supported by the Wombat. These include country-specific keyboard layouts like British, Canadian French, Danish, Greek, AZERTY variants, QWERTZ, and others. You’ll need to select the appropriate keyboard type in your operating system’s keyboard control panel, in order for the key mappings to work correctly.



System 7 Keyboard Control Panel

Two specific keys on ISO keyboards may require extra attention. If the key above TAB incorrectly behaves like the key to the right of LEFT SHIFT, you can switch ISO mode on/off to correct it. See details in the Help Commands section.



ISO Keyboard Key Swap

USB-to-ADB – Best results are obtained with Apple-brand country-specific USB keyboards, or any brand US-layout USB keyboards. In many countries, the country-specific PC-type USB keyboards have a different symbol layout than Apple ADB keyboards. These PC-type USB keyboards may be used, but key mappings for some symbols will be incorrect where differences exist between the Apple and PC-type layouts.

ADB-to-USB with Mac OSX – The first time you connect the Wombat to a modern Mac, a wizard will appear and attempt to detect the keyboard type. For non-US keyboards, you should select an ISO keyboard type from the wizard. If the key above TAB incorrectly behaves like the key to the right of LEFT SHIFT, even when the Wombat is in ISO mode, you may need to delete the OSX keyboard preferences to force the wizard to run again. Set the Wombat to ISO mode, delete the file /Library/Preferences/com.apple.keyboardtype.plist, restart the computer, and follow the wizard steps when it reappears.



Windows 7 Text Services and Input Languages Control Panel

ADB-to-USB with Microsoft Windows – Under Windows, when using country-specific ADB keyboards, you’ll need to select an Apple keyboard sub-type when choosing the keyboard type in the Windows preferences. The keyboard type is selected in the Text Services and Input Languages control panel. E.g. select a keyboard type of United Kingdom (Apple), French (Apple), or German (Apple) rather than the default United Kingdom, French, or German. If you don’t see the Apple sub-types listed, you’ll need to install the Apple keyboard driver applekeyboardinstaller64.exe.



Custom Key Mappings

With firmware version 0.3.0 or later, you can create your own customized key mapping tables. Change which keys behave as Command and Option, reassign the function keys to new purposes, or design other custom mappings. See the Wombat Keymap Tool for details.



What are ADB and USB?

ADB connector

From 1986 through 1998, ADB (Apple Desktop Bus) was the standard system for connecting peripherals like keyboards and mice to Apple computers. It was used by the Apple IIgs, as well as all early Macintosh models except the Mac Plus, 512K, and 128K. The ADB connector is a round mini DIN 4-pin, and is physically identical to the S-Video connector.

USB-A connector

USB (Universal Serial Bus) is the dominant standard today for connecting keyboards, mice, and other peripherals to a computer. Nearly everyone will recognize the familiar rectangular USB-A connector that’s used to plug a device into a host machine. USB replaced a variety of earlier standards like Firewire, ADB, and PS/2. Every Apple computer since 1998 has used USB for its input peripherals.

Converting between the two systems involves more than just a physical plug adapter. ADB and USB high-level protocols are fundamentally very different, and also have different signal speeds, signal formats, and voltages. ADB and USB input peripherals have different communication behaviors too. ADB keyboards and mice use event-based reporting, and only communicate when something has changed, whereas USB keyboards and mice communicate their full current state whenever asked.

Downloads



Older firmware versions: (try these if the latest version gives you problems)

adb-usb-wombat-0.3.4

adb-usb-wombat-0.3.3

adb-usb-wombat-0.3.2



ADB-USB Wombat latest firmware version: adb-usb-wombat-0.3.5 Older firmware versions: (try these if the latest version gives you problems)



Get One Now

Check out ADB-USB Wombat at the BMOW Store.

