Posts Tagged ‘Jagpad’

Using joypads on the Atari ST

August 30, 2009

The modern gamer is used to joypads in one form or another. The impact of 3rd generation video game consoles like the NES or the Sega Master System is tremendous. More importantly many younger gamers don’t even remember the classical joystick with switches. We oldtimers prefer them but regardless if you ask a seasoned gamer or an occasional gamer. If this person is not already used to oldschool joysticks, most of them dislike classic joysticks and will ask you for a joypad of some sort for playing on your ST.

Playing on the PC with an emulator makes the situation very easy. Just buy a suitable gamepad with USB connector, plug it in and any emulator worth to be used for gaming will allow you to use it. Starting from 7€ up to any price imaginable, you can find plenty of suitable joypads in your preferred computer hardware store.

But how about using joypads if you want to enjoy the games on the real hardware? How to connect joypads to the ST instead of the classic joystick?

The first solution is to get an old Sega gamepad for the Sega Master System. Those simply work by plugging into the ST’s joystick ports.

From Atari themselves there are at least 2 gamepads available which are suitable for use with the ST.

Atari Jaguar Powerpad Controller

Atari Jaguar Powerpad Controller

The first solution is the Jaguar powerpad. If you have an Atari STE or a Falcon 030, you can plug them into the extended joystick ports and they will work. However this solution has a drawback. Any software or game which wants to use them this way has to provide a special code to read the new ports. If the game does not support the STE extended joystick ports with Jagpads you are out of luck. This also applies if your ST simply does not have the Extended Joystick Ports, like the Mega STE or any STFM.

To make use of the Jaguar powerpad on any ST and with any ST game with joystick support one has to find a way to connect the jagpad to the ordinary joystick port. However neither plugs do fit nor are the joysticks of the same electrical construction. Luckily it is relatively easy to achieve a proper signal mapping. Take note that all fire buttons will act as the same fire button. It is impossible to map them to other functions.

Schematic for Jagpad to Atari ST adaptor

Schematic for Jagpad to Atari ST adaptor

The Atari Extended Joystick Port FAQ  [1] includes a entirely passive circuit which allows to connect the jagpad to a standard joystick port. Building this adaptor will give you the benefit to use the Jaguar powerpad on all computer systems with the DB9 connector.

World of Atari at [2] seems to have professional Jagpad adaptors for sale as well.

The second solution from Atari is the CX78 Joypad. This special joypad was marketed in Europe together with the ill-fated 7800 console but it basically works with the Atari ST as well. However it has a drawback. The pin usage on the CX78 joypad is slightly different to take care of the 2 separate firebuttons of the 7800. These signals confuse the IKBD, a small microcontroller in the Atari ST which processes all keyboard and joystick input. As soon as you plug a CX78 into an Atari ST, the machine will show strange behaviour on keyboard input. For some games, esp. selfbooting ones which do not require keyboard interaction, this is ok but for others, like the notorious Automation menus, you might end up to be unable to launch your game with the CX78 plugged in.

Atari CX78 joypad

Atari CX78 joypad

This problem could be solved by building an adaptor which will leave the non-standard signals unconnected from the ST, e.q. just routing GND, the 4 directions and the combined (or one) fire buttons to the ST.

A professional solution for connecting a joypad is also available. The JeST device allows to connect Playstation joypads to the ST and other old computer systems with the DB9 joystick standard. However I didn’t receive mine yet so I can’t comment on its special features yet. A future article will deal with the JeST. In the meantime, you can find out more at [3] or alternatively at

This device should be handy for all gamers who also have a Playstation at home which gets as much use as the Atari ST.

A neat trick is to take a non functional old joystick and a working USB joypad. Even if the USB part is defective, the mein push buttons of the pad are likely to be intact. Just solder some cables from the USB pad internals to the appropriate contacts on the ST joystick. If done properly, it should simply work as intended, bypassing the buttons of the old joystick and using the buttons from the gamepad instead.

As a last resort you can build your own because any joystick or joypad. On the ST this is simply a set of 5 switches which ground the control lines for the four directions or the fire button if pressed.

Also I’ve seen hacked MSX joypads rewired to work with an Atari 800XL so basically this should be possible to do for the Atari ST aswell.

Be creative – there are many ways to connect a joypad instead of a classic joystick!


  1. The Atari Enhanced Joystick Ports FAQ
  2. World of Atari
  3. Logicsays