ATEN KVM Table

Pin assignment for the ATEN standard KVM cable using a 15-pin HDB-15 connector to carry VGA video and two PS/2 channels between computer and KVM switch.

The ATEN standard KVM cable (2L-1001P family) connects a computer to an ATEN KVM switch using a 15-pin HDB-15 (DB-15) connector that bundles VGA video, PS/2 keyboard, and PS/2 mouse signals into a single plug on each end. The computer end presents an HDB-15 male plus a 6-pin mini-DIN male (PS/2) for each input device, whilst the KVM-switch end uses the combined HDB-15 form. ATEN also produces an SPHD-15 variant with a proprietary modified connector; ATEN has not published a public pinout for those SPHD cables and the connector shape is deliberately non-standard to prevent third-party substitution. The PS/2 keyboard and mouse interface was introduced by IBM with the Personal System/2 line in 1987, using a 6-pin mini-DIN connector; pins 1 and 5 carry data and clock respectively, with pins 3 and 4 serving ground and +5 Vdc.

15 pin D-SUB male connector layout 15 pin D-SUB male connector to the KVM

15 pin D-SUB male connector diagram 15 pin D-SUB male connector to the Computer

KVM NameKVM PinDirectionComputer PinComputer NameDescription
red11redVideo RED
green22greenVideo Green
blue33blueVideo Blue
Keyb Data4Keyb PS/2, Pin 1
Keyb Clock5Mouse PS/2, Pin 5 (Clk)
GND/Video6678GND/Video
GND75GNDVGA/10, Mouse/3, Keyb/3
Mouse Clk8Mouse PS/2, Pin 5 (Clk)
Keyb VCC9Keyb PS/2, Pin 4 (VCC)
GND1010GNDVGA/5, Mouse/3, Keyb/3
Mouse Data11Mouse PS/2, Pin 1
ID11212ID1
HSync1313HSync
VSync1414VSync
ID31515ID3

Signals

  • red — VGA red analogue video signal
  • green — VGA green analogue video signal
  • blue — VGA blue analogue video signal
  • Keyb Data — PS/2 keyboard data (open-collector; corresponds to pin 1 of the 6-pin mini-DIN)
  • Keyb Clock — PS/2 keyboard clock (open-collector; corresponds to pin 5 of the 6-pin mini-DIN)
  • GND/Video — ground return for VGA video signals (corresponds to VGA pins 6, 7, 8)
  • GND — common ground shared by VGA and both PS/2 channels
  • Mouse Clk — PS/2 mouse clock (open-collector; corresponds to pin 5 of the 6-pin mini-DIN)
  • Keyb VCC — +5 Vdc supply for PS/2 keyboard (corresponds to pin 4 of the 6-pin mini-DIN); Vcc range +4.5 V to +5.5 V, max device current 275 mA
  • Mouse Data — PS/2 mouse data (open-collector; corresponds to pin 1 of the 6-pin mini-DIN)
  • ID1 — monitor identification bit 1 (DDC legacy)
  • HSync — VGA horizontal synchronisation
  • VSync — VGA vertical synchronisation
  • ID3 — monitor identification bit 3 (DDC legacy); function not publicly documented for KVM use

Notes

  • The HDB-15 combined connector is used at the KVM-switch end; at the computer end the cable separates into an HDB-15 (VGA) and two 6-pin mini-DIN (PS/2) plugs.
  • Similar-looking LevelOne KVM cables use a different pinout and are not interchangeable.
  • ATEN SPHD-15 cables (2L-5201P / 2L-5202P family) carry the same signals in a proprietary connector; ATEN has not published a public pinout for those cables.
  • PS/2 data and clock lines are open-collector, pulled to +5 Vdc via pull-up resistors; lines remain high when idle and can tolerate reconnection without system disruption if power is maintained.

References

Category:Input Device Cables