This is the cable connector for NCR powered serial connector, as found on the realpos series.
|Description (may be empty)|
|9||+12V||+12V if 1,4 and 6 are shorted|
PC toggles a bit on the DTR line and check the DSR and DCD lines. If the lines are shorted, pin 9 (normally RI) is used to provide 12V power. See patent for more information