APC Dumb UPS cable (simple)

This cable can only be used on voltage-signalling UPSes, and provides the On Battery signal as well as kill UPS power (and may be Low Battery signal).

     APC Part# - 940-0020B (investigated by apcupsd team)

     Signal Computer                  UPS
            DB9F                     DB9M
      CTS    8   --------------------  2  On Battery
      DTR    4   --------------------  1  Kill power
      GND    5   ---------------*----  4  Ground
                                |
                     ---        *----  9  Common
      DCD    1  ----|///|-----------   5  Low Battery
                    |\\\|
      RTS    7  ----|///| (probably a
                     ---   semi-conductor)

Full scheme of 940-0020C isn't yet known.

     APC Part# - 940-0020C (investigated by apcupsd team)

     Signal Computer                  UPS
            DB9F                     DB9M
      CTS    8   --------------------  2  On Battery
      DTR    4   --------------------  1  Kill power
      GND    5   ---------------*----  4  Ground
                                |
                                *----  9  Common
      RTS    7 -----[ 93.5K ohm ]----- 5  Low Battery
                    or semi-conductor

Our users reports that the 20C is designed to mimic a mouse movement when it received an on battery signal from the Back-UPS. Therefore the computer will wake up and shutdown properly. The 20B cable does not have this functionality.