this file contains info to connect lines between pc and apple 

1.apple  game i/o pins

          to keyboard side               as an apple  user, you'll see
          ^^^^^^^^^^^
         +---+ +---+                            +----------+
     +5  |1  +-+ 16| none                  none | 9       8| GND
     PB0 |2      15| AN0                    GC1 |10       7| GC2
     PB1 |3      14| AN1                    GC3 |11       6| GC0
     PB2 |4      13| AN2                    AN3 |12       5| strobe
  strobe |5      12| AN3                    AN2 |13       4| PB2
     GC0 |6      11| GC3                    AN1 |14       3| PB1
     GC2 |7      10| GC1                    AN0 |15       2| PB0
     GND |8      9 | none                  none |16 +--+  1| +5
         +---------+                            +---+  +---+
                                              since keyboard is in
          back board side                         this direction

2.pc parallel port 25-pin
  please buy a 25-pin "jump wire connector"
  (for rs-232 is ok , they both are 25-pin)

        |\
        | \
      1 |  \
      2 |   \
      3 |    | 14
      4 |    | 15
      5 |    | 16
      6 |    | 17
      7 |    | .
      8 |    | .
      9 |    | .
     10 |    | .
     11 |    | 25
     12 |   /
     13 |  /
        | /
        |/

3.line connection:  9 lines total
  apple --- pc
    GND     pin 25         as GND
    PB0     pin 2          as apple side handshake in (apple -> pc);data bit 0
    PB1     pin 3          apple input data bit 1
    PB2     pin 4          apple input data bit 2
    GC0     pin 5          as apple side handshake in (pc -> apple)
    AN0     pin 15         apple output data bit 0
    AN1     pin 13         apple output data bit 1
    AN2     pin 12         apple output data bit 2
    AN3     pin 10         apple side handshake out