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Chapter 4: Motherboard Connections
COM Port
The motherboard has two COM headers (COM1/2, COM3/4) that provide four serial
connections and support RS-232 function, utilizing Supermicro PN: CBL-CUSB-0984 (not
included).
COM Header (COM1/2, COM3/4)
Pin Definitions
Pin#
Definition
Pin#
Definition
1
DCD4
2
DSR4
3
RXD4
4
RTS4
5
TXD4
6
CTS4
7
DTR4
8
RI4_N
9
GND
10
N/A
11
DCD3
12
DSR3
13
RXD3
14
RTS3
15
TXD3
16
CTS3
17
DTR3
18
RI3_N
19
GND
20
N/A
4-pin External BMC I
2
C Header
A System Management Bus header for IPMI 2.0 is located at JIPMB1. Connect a cable to
this header to use the IPMB I
2
C connection on your system. Refer to the table below for pin
definitions.
External I
2
C Header
Pin Definitions
Pin#
Definition
1
Data
2
Ground
3
Clock
4
No Connection
Power SMB (I
2
C) Header
Power System Management Bus (I
2
C) header at JPI
2
C1 monitors the power supply, fan and
system temperatures. Refer to the table below for pin definitions.
Power SMB Header
Pin Definitions
Pin#
Definition
1
Clock
2
Data
3
Power Fail
4
Ground
5
+3.3V
