Apple IIc Plus Joystick - DB 9 Pin connector
The Apple IIc Plus (1988) provides a single 9-pin D-type miniature (DE-9) female connector on the rear panel that serves as the combined hand controller and mouse port. It exposes two analogue paddle inputs (PDL0 and PDL1), each driven by a 150 kΩ variable resistor connected to +5 V, and two pushbutton switch inputs (GAMESW0 and GAMESW1); the port’s NE556 dual timer RC network (with 0.022 µF capacitors) times the resistor–capacitor voltage decay, which software reads by addressing $C07x to determine pot position. Unlike the Apple IIe’s internal 16-pin game connector, the IIc Plus external DE-9 port does not carry annunciator outputs, PDL2, PDL3, or Pushbutton2. The same physical connector functions in mouse mode, repurposing several pins for direction and movement signals.
Analog
| Pin | Signal | Description |
|---|---|---|
| 1 | GAMESW1 | Switch input 1 (sometimes called paddle button 1). |
| 2 | +5V | total current drain from this pin must not exceed 100mA. |
| 3 | GND | System ground. |
| 4 | Not Used for hand controller. | |
| 5 | PDL0 | hand controller input. Must be connected to a 150K ohm variable resistor connected to +5V. |
| 6 | N.C. | Not connected. |
| 7 | GAMESW0 | Switch input 0 (sometimes called paddle button 0). |
| 8 | PDL1 | hand controller input; must be connected to a 150K ohm variable resistor connected to +5V. |
| 9 | Not used with hand controller. |
Digital
| Pin | Signal | Description |
|---|---|---|
| 1 | MOUSEID* | Mouse identifier: when active, disables NE556 hand controller timer. |
| 2 | +5V | total current drain from this pin must not exceed 100 mA. |
| 3 | GND | System Ground. |
| 4 | XDIR | Mouse X-direction indicator. |
| 5 | XMOVE | Mouse x-movement interrupt. |
| 6 | N.C. | Not connected. |
| 7 | MSW* | Mouse button. |
| 8 | YDIR | Mouse Y-direction indicator. |
| 9 | YMOVE | Mouse Y-movement interrupt. |
Notes
- The DE-9 connector is a female socket on the computer; joystick and mouse plugs present a male DE-9.
- Total current drawn from Pin 2 (+5V) must not exceed 100 mA.
- PDL2, PDL3, and Pushbutton2 — present on the Apple IIe’s internal 16-pin game port — are not available on this external DE-9 port.
- Annunciator output signals are likewise absent from the IIc Plus external connector.
- The IIc Plus uses the NE556 dual 555-type timer for the two analogue paddle inputs; the NE558 quadruple timer used in the older Apple II and II+ is not fitted here.
- The pin assignments of the IIc Plus hand controller port are identical to those of the original Apple IIc (1984); the IIc Plus added a 4 MHz accelerated mode but left the game port hardware interface unchanged.
Signals
Analogue (joystick/paddle) mode
- GAMESW1 — switch input 1; paddle pushbutton 1 (Pin 1)
- +5V — 5 V supply; maximum 100 mA total current draw (Pin 2)
- GND — system ground (Pin 3)
- PDL0 — analogue input 0 (X-axis); requires a 150 kΩ variable resistor to +5V (Pin 5)
- N.C. — not connected (Pin 6)
- GAMESW0 — switch input 0; paddle pushbutton 0 / fire button (Pin 7)
- PDL1 — analogue input 1 (Y-axis); requires a 150 kΩ variable resistor to +5V (Pin 8)
Digital (mouse) mode
- MOUSEID* — mouse identifier; when active, disables the NE556 hand controller timer (Pin 1)
- +5V — 5 V supply (Pin 2)
- GND — system ground (Pin 3)
- XDIR — mouse X-direction indicator (Pin 4)
- XMOVE — mouse X-movement interrupt (Pin 5)
- N.C. — not connected (Pin 6)
- MSW* — mouse button (Pin 7)
- YDIR — mouse Y-direction indicator (Pin 8)
- YMOVE — mouse Y-movement interrupt (Pin 9)