9 PIN D-SUB MALE at the computer.
9 PIN D-SUB FEMALE at the mouse/joy cable.
The Amiga family (A1000, A500, A2000, A3000) provides two 9-pin DE-9 controller ports, one assigned to the mouse and one to a joystick, though any port can accept any supported device. Defined in the Amiga Hardware Reference Manual, the interface handles quadrature-encoded mice, digital joysticks, light pens, and proportional paddle controllers through the same physical connector. Paula hardware counters decode quadrature pulses directly, whilst analogue inputs on pins 5 and 9 feed the POTX/POTY measurement circuit driven by the POTGO register.
| Pin | Mouse/Trackball | Lightpen | Digital Joystick | Paddle | Dir | Comment |
|---|---|---|---|---|---|---|
| 1 | V-pulse | n/c | /FORWARD | BUTTON 3 | IN | |
| 2 | H-pulse | n/c | /BACK | n/c | IN | |
| 3 | VQ-pulse | n/c | /LEFT | BUTTON 1 | IN | |
| 4 | HQ-pulse | n/c | /RIGHT | BUTTON 2 | IN | |
| 5 | BUTTON 3(M) | Penpress | n/c | PotX | IN/OUT | |
| 6 | BUTTON 1(L) | /Beamtrigger | /BUTTON 1 | n/c | IN/OUT | |
| 7 | +5V | +5V | +5V | +5V | OUT | 125 mA max |
| 8 | GND | GND | GND | GND | ||
| 9 | BUTTON 2(R) | BUTTON 2 | BUTTON 2 | PotY | IN/OUT |
Notes
- Direction is Computer relative Device.
- Pot is a linear 470 kOhm (±10 %)
- The +5V supply on pin 7 is limited to 125 mA maximum.
- Pins 5, 6, and 9 can be reconfigured as outputs via the POTGO register for custom peripherals.
Signals
- V-pulse / VQ-pulse — Quadrature-encoded vertical mouse movement on pins 1 and 3; Paula decodes the phase relationship to determine direction and speed.
- H-pulse / HQ-pulse — Quadrature-encoded horizontal mouse movement on pins 2 and 4.
- /FORWARD, /BACK, /LEFT, /RIGHT — Active-low digital joystick direction inputs read via CIA-A port bits.
- BUTTON 1(L) / /BUTTON 1 — Left mouse button or joystick fire button; routes through CIA-A port bit 6.
- BUTTON 2(R) — Right mouse button or second joystick button; routes through CIA-A port bit 7.
- BUTTON 3(M) / UBUT — Middle mouse button; shares pin 5 with the POTX analogue input and Penpress.
- PotX / PotY — Analogue proportional inputs on pins 5 and 9 for paddle controllers; recommended potentiometer value 470 kOhm ±10 %, maximum 528 kOhm. Measurement is triggered by a write to the POTGO register during vertical blanking; results are read from POT0DAT or POT1DAT.
- Penpress / /Beamtrigger — Light pen inputs: Penpress signals stylus contact; /Beamtrigger is active-low and fires on beam coincidence.
- +5V — Power supply, 125 mA maximum.
- GND — Signal and power ground.
References
- Amiga Hardware Reference Manual, 2nd Edition — Addison-Wesley Publishing Company, Inc. (for Commodore-Amiga, Inc.), ISBN 0-201-18157-6, September 1989
- Amiga Hardware Reference Manual, 3rd Edition — Commodore-Amiga, Inc., 1991