NA121
Motherboard
3
NA121 Motherboard Layout
A
CPU Socket
H
Front Side USB
B
CPU Fan Socket
I
COM Port
C
Memory Sockets
J
Expansion Slots
D
Power Supply Connectors
K
Audio Connector
E
Floppy Connector
L
Jumper Connector
F
IDE Connectors
M
Back Panel Connectors
G
Front Panel Connector
Front Panel Connector Pin Definition
Pin
Signal Name
I/O
Description
1
HDD LED+
O
Pull up 330ohm to VCC
2
Suspend LED-
O
SUS LED
3 HDD
LED-
O
IDEACTP-
4
Suspend LED+
O
Pull up 330ohm to VCC
5 H/W
reset-
- GND
6
Power
I
Pull up 1Kohm to VCC
7
H/W
reset+ I
HWRST
SW
8
Power
Button- -
PWRBTIN
9 VCC
- VCC
10
EXT, SMI+
I
Pull up 8.2Kohm to 3.3V
11 IRRX
I IRRX
12 EXT,
SMI-
- GND
13 GND
- GND
14
KEY
- KEY
15 IRTX
O IPTX
16 Power
LED+
O VCC
17 CIRRX
- CIRRX
18
NC -
NC
19
NC -
NC
20 Power
LED-
- GND
A
B
C
D
E
F
G
J
H
D
K
M
L
I
