I-PAC 4 Arcade Encoder Arcade Encoders Ultimarc - Retro Active Arcade
I-PAC 4 Arcade Encoder Arcade Encoders Ultimarc - Retro Active Arcade I-PAC 4 Arcade Encoder Arcade Encoders Ultimarc - Retro Active Arcade
Stock Level: 2
$87.99 CAD

I-PAC 4 Keyboard Arcade Encoder

I-PAC; The world's most advanced PC interface for buttons and joysticks.  (Click Here For Wiring Diagram)

  • I-PAC 4 has 56 inputs each with it's own dedicated microprocessor pin. No interaction or delays, vital for multi-button games such as fighting games.

  • I-PAC is much more than a keyboard encoder! Pins can be configured as mouse buttons or game controller buttons, plus power and volume control.

  • Multi-mode functionality enables interface to be switched into dual gamepad mode or dual Xinput controller mode.

  • I-PAC in key mode breaks through the USB simultaneously-pressed-switch limit of 6 switches (plus ctrl,alt,shift) which afflicts all USB keyboard devices. This is beacuse it has inbuilt full native USB support, and does not rely on an add-on adaptor.

  • I-PAC has a shift function which allows ANY input to be assigned to a shifted secondary keycode and the shift button can have it's own function too so no need for a dedicated extra control panel button.

  • I-PAC has a self-test LED which not only gives an instant visible check of your installation but also can indicate which connection (if any) is causing a problem.

  • I-PAC retains it's programming including operation mode after power off. Beware! Not all keyboard encoders do this!

  • I-PAC 4 does not have a trackball or spinner connection on the board.

The I-PAC (Interface for Pc to Arcade Controls) are a range of boards which allow connection of arcade controls such as buttons and joysticks to a USB port on a PC motherboard or other host system. It was designed around the MAME emulator which supports over 1000 arcade games and can be used with other emulators or any software which requires keyboard or game controller input.

It is designed to be used inside an Arcade Games cabinet with the PC motherboard also mounted inside, but could just as easily be used with simply a control panel without a cabinet.

Special shift function buttons mean that a normal keyboard is only be needed for game loading and configuration, not for gameplay. All key codes can be programmed but you dont have to as you can use the built-in default configuration which has all standard MAME codes for quick and easy installation. Programmed keys codes are stored even after power off.

The I-PAC 4 has 56 inputs. They are all programmable and are marked as 4 joysticks, 8 buttons each, plus coin1, coin2, start1, start2 and Mame control keys. Any inputs can be assigned as a shift key to access an alternate code set.

When using a U-Trak Trackball or SpinTrak Spinner with this board, they can be ordered with their own optional USB interfaces. Note the 9-pin header on the I-PAC 4 is for factory use only.


  • 1x I-PAC 4 Arcade Encoder
  • 1x USB Cable

Item Features:

  • Fully programmable key code set. Stored even after power off unlike some other interfaces which lose all data when powered off.

  • Controls can be assigned to any keycode, game controller button, plus mouse buttons, power, sleep or wake.

  • All joystick/button connections easily made via screw tag strip. Connections marked on the board.

  • Chunky 5mm screw connectors.

  • Self-Test LED gives an instant check of all your wiring. Can indicate which, if any, input has a problem.

  • All button inputs referenced to ground - no need to re-wire separate grounds to each button.

  • Lead plugs into USB port.

  • Using host software, an unlimited number of keycode configurations can be stored and downloaded on-the-fly. Retained on power off.

  • No separate power needed.

  • Does not use a matrix - no ghost keys.

  • Does not use a scanning method which causes a variable delay. Each input has it's own dedicated connection into the on-board CPU.

  • Fast running interrupt-driven software gives much better response than a standard keyboard controller. Key debounce uses a state method for each key. No delays between keys depressed at the same time. (essential for fighting games).

  • Either uses standard MAME keys or you can program your own character set.

  • Shift functions. Holding "Start1" and pressing other buttons sends a range of codes for MAME functions such as "escape", "Coin 1", "tab", "enter". This means no extra buttons are needed on the cabinet. In programmable mode any input can be the shift key and all keys can be programmed with a shifted code.

  • Special note for Windows MAME users! Shift key functions mean you can select and start games from the Windows interface without using the keyboard or mouse.

  • No special drivers needed. USB drivers are generic Windows.

  • Fully compatible with all Apple Macs which have USB ports.

  • Supports the Apple Mac "command" key and the Windows "GUI" keys.

  • Keycode programming is integrated directly into many popular front ends for seamless launch of emulator or other applications which require different code sets.

Item Installation:

The MAME control keys are by default assigned to the "A" and "B" inputs. Check out the code table here for all default assignments.

Using The Built-In Code Set:

When the board is first powered on, it operates in keyboard mode and contains a pre-loaded code set. This matches the MAME default key codes as the table above indicates. For many users there is no need to do any re-assignment, just power up and play.

You may want to re-program the codes if any of the following apply:

  • You use an emulator or other PC application without a key re-mapper.

  • You don't want people to be able to access the MAME game config menus by using shift buttons (for example game contests etc)

  • You want to limit coin insert to a real coin slot rather than using shift button feature.

Technical Info

Item Technical Info:

  • The I-PAC uses a high-performance micro-controller chip . No matrix or diodes are used hence absolutely no ghosting, blocking or delays.

  • De-bounce. This uses a state counter method. Each input has it's own counter. This means simultaneous key presses are never locked out.

  • Key code Flash ROM storage. Retains custom settings after power off/on (excluding I-PAC VE)

  • Full Speed USB 2.0 compatible.

  • Shift key logic including protection against stuck keys.