Adaptec SBC-599, SBC-596 manual Front panel connectors CN1,CN2,CN3,CN4, Speaker connector CN1

Front panel connectors (CN1,CN2,CN3,CN4)

You may want to install external switches to monitor and control the SBC-596/599. These features are optional —install them only if you need them. The front panel connectors include a speaker connector (CN1), a HDD LED connector (CN2), an input switch (CN3) for resetting the card, and a keyboard lock connector (CN4).

Speaker connector (CN1)

The SBC-596/599 can drive an 8 W speaker at 0.5 watts. Ensure that alternatives to this specification do not overload the card. Close pins 3 and 4 to enable the buzzer.

HDD LED connector (CN2)

The LED indicator for hard disk access is an active low signal (24 mA sink rate).

Reset switch (CN3)

If you install a reset switch, it should be an open single pole switch. Momentarily pressing the switch will activate a reset. The switch should be rated for 10 mA, 5 V.

Power LED/keyboard lock connector (CN4)

You can connect an LED to indicate if the CPU card is powered on. Pin 1 of CN4 supplies power to the LED, and pin 3 is the ground.

You can use a switch (or a lock) to disable the keyboard. In this state, the PC will not respond to any input from the keyboard. This is useful if you don’t want anyone to change or stop a running program. Simply connect the switch between pin 4 and pin 5 of CN4.

If you need to make your own cable, you can find the pin assign- ments for the board’s connector in Appendix B.

20 SBC-596/599 User's Manual