# CD32 Keyboard to Serial Interface 1

    For the signal-translation form the 0-5VDC source to the standard
    RS232-level (-12VDC / +12VDC) you may choose the MAX232 or an
    equivalent counterpart (ICL232 ....)
    CD32 Keyboard-Port      level-converter TTL->RS232     RS232

    Pin4 +5V -------------Pin16
    Pin3 GND -------------Pin15--------------------------GND Pin7
    Pin2 TxD ------------>Pin10  (---|>*-)  Pin7-------->RxD Pin3
    Pin6 RxD <------------Pin9   (--*<|--)  Pin8<--------Txd Pin2
                   C1
                 +--)|----Pin1                      +----DSR Pin6
                 |    +                         (*) |
                 +--------Pin3                      +----DCD Pin8
                   C2                               |
                 +--)|----Pin4                      +----DTR Pin20
                 |    +
                 +--------Pin5                      +----RTS Pin4
                   C3                           (*) |
               GND--|(----Pin6                      +----CTS Pin5
                   +    (Polung!)

                   C4
               GND--)|----Pin16          (*) some computers need these
                      +                  handshake connections to
                   C5                    proper working
                 +--|(----Pin16
                 | +    (Polung!)
                 +--------Pin2

                              (**)
    shielding-----------------------------------------| |-shielding

    connect the shielding of all cables to each other - but only
    connect it to only ONE interface port connector (i used the
    keyboard plug).

    For the condensers C1..C5 you must get 1 uF electrolyt-condesers.
    If your signal-converter is kind of the xxx232A (A-type) you must
    use 0.1 uF instead (for C1..C5)       [source : Maxim Data Book]

    Be careful with your explorations. I suggest the serial signals
    are passed through directly to the PAULA chip - so they are
    slightly sensitive.

Contributor: Joakim Ögren

Source:
CD32 keyboard port info usenet posting by Klaus Hegemann

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May be copied and redistributed, partially or in whole, as appropriate.
Document last modified: 2001-06-07