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26
MB991AF
User’s Manual
2.5.8
Front Panel Setting Connector (J21)
1
2
8
7
Pin
Assigment
Pin
Assigment
1
Power BTN
2
Power BTN
3
HDD LED+
4
HDD LED-
5
Reset BTN
6
Reset BTN
7
Power LED+
8
Power LED-
J21 is utilized for system indicators to provide light indication of the computer
activities and switches to change the computer status. It provides interfaces
for the following functions.
•
ATX Power ON Switch (Pins 1 and 2)
The 2 pins makes an
“ATX Power Supply On/Off Switch” for the system
that connects to the power switch on the case. When pressed, the
power switch will force the system to power on. When pressed again, it
will power off the system.
•
Hard Disk Drive LED Connector (Pins 3 and 4)
This connector connects to the hard drive activity LED on control panel.
This LED will flash when the HDD is being accessed.
•
Reset Switch (Pins 5 and 6)
The reset switch allows you to reset the system without turning the
main power switch off and then on again. Orientation is not required
when making a connection to this header.
•
Power LED: Pins 7 and 8
This connector connects to the system power LED on control panel.
This LED will light when the system turns on.