ETX-945 User Manual 1.00 www.diamondsystems.com Page 30
4.4.4 Miscellaneous signals
These pins implement the ETX-945’s I2C and SM Bus interfaces, PC-speaker output, and RTC/CMOS bac kup
power input.
Signal Name
Signal Function
Direction
SPEAKER
This logic-level signal can drive a piezoelectric speaker
(typically via a transistor)
O
BATT
2.4V to 3.3V DC backup power input for RTC and CMOS
RAM; typically connects to an external 3V lithium cell
I
I2CLK
Bidirectional I2C Bus clock signal
I/O
I2DAT
Bidirectional I2C Bus data signal
I/O
SMBCLK
Bidirectional SM Bus clock signal
I/O
SMBDATA
Bidirectional SM Bus data signal
I/O
KBINH#
Keyboard inhibit signal
In
OVCR#
USB over-current detected
In
ROMKBCS#
Reserved; do not connect
n/a
EXT_PRG
Reserved; do not connect
n/a
GPCS#
Reserved; do not connect
n/a
4.5 SATA Connectors
The ETX-945 provides two SATA (Serial ATA) drive interfaces on a pair of 7-pin connectors located o n the top
side of the board. The position and pinout of each of these connectors is compliant with the ETX 3.0 Specification.
The signal assignment appears below.
1
GND
2
TX+
3
TX-
4
GND
5
RX+
6
RX-
7
GND