Figure D-4
Game port pin-outs

1

2

3

4

5

Switch—Option

+5 volts

Signal ground

Paddle 2

Paddle 0

6

7

8

9

Switch 2

Switch 0—Open Apple

Paddle 1

Paddle 3

The game I/O signals are also available on a 16-pin DIP socket labeled GAME I/O on the main circuit board inside the case. (See Figure D-9.)

Figure D-5
Disk drive port pin-outs

1

2

3

4

5

6

7

8

9

10

Signal ground

Signal ground

Signal ground

3.5-inch disk

-12 volts DC

+5 volts DC

+12 volts DC

+12 volts DC

Enable 2

Write-protect

11

12

13

14

15

16

17

18

19

Seek phase 0

Seek phase 1

Seek phase 2

Seek phase 3

Write request

Head select

Drive 2 enable

Read data

Write data

162

Appendix D: Apple IIGS Features and Specifications