External Connectors

Cartridge Slot

 Pin   Name    Expl.
 1     VDD     Power Supply +5V DC
 2     PHI     System Clock
 3     /WR     Write
 4     /RD     Read
 5     /CS     Chip Select
 6-21  A0-A15  Address Lines
 22-29 D0-D7   Data Lines
 30    /RES    Reset signal
 31    VIN     External Sound Input
 32    GND     Ground

Link Port

Pin numbers are arranged as 2,4,6 in upper row, 1,3,5 un lower row; outside view of gameboy socket; flat side of socket upside. Colors as used in most or all standard link cables, because SIN and SOUT are crossed, colors Red and Orange are exchanged at one cable end.

 Pin Name Color  Expl.
 1   VCC  -      +5V DC
 2   SOUT red    Data Out
 3   SIN  orange Data In
 4   P14  -      Not used
 5   SCK  green  Shift Clock
 6   GND  blue   Ground

Note: The original gameboy used larger plugs (unlike pocket gameboys and newer), linking between older/newer gameboys is possible by using cables with one large and one small plug though.

Stereo Sound Connector (3.5mm, female)

 Pin     Expl.
 Tip     Sound Left
 Middle  Sound Right
 Base    Ground

External Power Supply

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