Intel MB820 User Manual
Page 22
INSTALLATIONS
18
MB820 User’s Manual
J11: Digital I/O Connector (4 in, 4 out)
This 12-pin Digital I/O connector supports TTL levels and is used to
control external devices requiring ON/OFF circuitry.
Signal Name
Pin #
Pin #
Signal Name
IN0
1
7
+5V
IN1
2
8
OUT0
IN2
3
9
Ground
IN3
4
10
OUT1
GROUND
5
11
+12V
OUT2
6
12
OUT3
J12: System Function Connector
J12 provides connectors for system indicators that provide light
indication of the computer activities and switches to change the computer
status. J12 is a 20-pin header that provides interfaces for the following
functions.
Hard Disk Drive LED
Reset Switch
Not Defined
ATX Power On Switch
SMI / Hardware Switch
Power LED
Speaker
Speaker: Pins 1 - 4
This connector provides an interface to a speaker for audio
tone generation. An 8-ohm speaker is recommended.
Pin #
Signal Name
1
Speaker out
2
No connect
3
Ground
4
+5V