Pin   CDTV      A1000   A2/3000   CD32   A4000
 1    GND       +5V     KCLK      DATA   I/O
 2    KBDATA    CLOCK   KDAT      TxD    n/c
 3    KBCLOCK   DATA    NC        GND    Ground
 4    Vcc       GND     GND       +5V    +5VDC (100mA)
 5    KBSE              +5V       CLOCK  Clock
 6                                RxD    n/c
GND is ground.
+5V is positive 5 volts.
KCLK, CLOCK and KBCLOCK is keyboard clock.
I/O, KBDATA, KDAT and DATA is keyboard data.
TxD is RS-232 Transmit data.
RxD is RS-232 receive data.
KBSE is keyboard sense.
A1000 is RJ12 jack.
A2000/3000 is a 5-pin DIN female.
CD32 is a 6-pin miniDIN female.
A4000 is a 6-pin miniDIN female.
It has been reported that some very very very early Amiga 2000 keyboards
have a different pinout. If you can show me some documentation on this
I would be happy to postit here.