Magical Spot, Universal (1980)
------------------------------

56-pin edge connector
----------------------------------------------------
     GND            | 1  | A  |    GND
     GND            | 2  | B  |    GND
     +5v            | 3  | C  |    +5v
     +5v            | 4  | D  |    +5v
     +12v           | 5  | E  |    +12v 
     -5v            | 6  | F  |    -5v
     GND            | 7  | H  |    GND
     +18v           | 8  | J  |    +18v 
     N/C            | 9  | K  |    N/C
     COIN SW GND    | 10 | L  |    AUDIO
     N/C            | 11 | M  |    AUDIO
     N/C            | 12 | N  |    RESET (TILT)
     N/C            | 13 | P  |    N/C
     N/C            | 14 | R  |    N/C
     1P RIGHT       | 15 | S  |    2P RIGHT
     N/C            | 16 | T  |    N/C
     N/C            | 17 | U  |    N/C
     N/C            | 18 | V  |    N/C
     1P LEFT        | 19 | W  |    1P LEFT
     N/C            | 20 | X  |    N/C
     1P START       | 21 | Y  |    2P START
     1P FIRE        | 22 | Z  |    RED
     2P FIRE        | 23 | a  |    GREEN
     COIN COUNTER 2 | 24 | b  |    BLUE
     COIN COUNTER 1 | 25 | c  |    SYNC
     COIN 2         | 26 | d  |    GND
     COIN 1         | 27 | e  |    GND
     GND            | 28 | f  |    GND