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Best power CheckUPS II basic serial cable wiring

These diagrams are reverse engineered from the CheckUPS source.
Various examples use 10 kΩ pull up resistors, but this doesn't work with all serial ports, so I use 4700 Ω instead.

INT0027

This cable is probably obsoleted.
Wiring shutdown to DTR isn't a good idea anyway.

DTR -----------> Shutdown
             1

TXD -----------+
               |
RTS ----+      |
        |      |
       +++    +++
       | |    | |
       +++    +++
        |      |
DCD ----*      |
        |      |
RXD -----------*
        | 5    | 3
        o  /   o  /
         /      /
        *      *
        |      |
GND ----*------+
       4

1 = Shutdown
3 = Low Mains
4 = GND
5 = Low Batt

INT0051

RTS -----------> Shutdown
             1

DTR ----*------+
        |      |
       +++    +++
       | |    | |
       +++    +++
        |      |
DCD ----*      |
        |      |
CTS -----------*
        | 5    | 3
        o  /   o  /
         /      /
        *      *
        |      |
GND ----*------+
       4

Below a cable with a DB-25 at the PC side;

PC             UPS

 4 ----------- 1

 5 ----*------ 3
       |
      +++
      | | 4k7
      +++
       |
20 ----*
       |
      +++
      | | 4k7
      +++
       |
 8 ----*------ 5

 7 ----------- 4

And one with a DE-9

PC             UPS

 7 ----------- 1

 8 ----*------ 3
       |
      +++
      | | 4k7
      +++
       |
 4 ----*
       |
      +++
      | | 4k7
      +++
       |
 1 ----*------ 5

 5 ----------- 4

The resistors are mounted inside the connector shell at the PC side.
The shield is connected to the connector shell at both sides of the cable.

The usual disclaimers apply.