ALIX system board
14
5/5/2010
1
V3
3.3V supply
2
TXD
transmit data (output)
3
RXD
receive data (input)
4
GND
ground
J12 / J4 / J12
COM2 serial port (build option)
As an option, the board can be configured with a 4 or 5 pin header with 3.3V CMOS signal levels
instead of the normal RS-232 serial port.
On alix.2c / alix.3c boards, this port is connected in parallel to COM1, need to remove MAX3243
serial driver to use.
Alix.2c / alix.2d -> please add a 1K or 2.2K ohm pull-up resistor to 3.3V on the TXD line.
1
V3
3.3V supply
2
TXD
transmit data (output)
3
RXD
receive data (input)
4
GND
ground
5
VCC
5V supply
J3/J1 / J3
Ethernet port 1
RJ45 connectors with integrated magnetics are used. This port implements a passive power over
Ethernet scheme over the two unused pairs. Do not exceed 20V as the TVS protection diode may
start clamping above this voltage.
1
TX+
transmit positive
2
TX-
transmit negative
3
RX+
receive positive
4
VIN
power supply (nominal 7 to 20V)
5
VIN
“
6
RX-
receive negative
7
GND
power return
8
GND
“
J1, J2 / - / J1
Ethernet ports 2, 3
RJ45 connectors with integrated magnetics are used. These ports do NOT support power over
Ethernet. Same pinout as above, but pins 4,5 and 7,8 are not connected.
J6/J9 / J6
USB jack
Dual USB 2.0 connections. As a build option, 4 pin headers can be installed instead of the USB
connector.
1
VCC
sw5V supply
2
DATA2-
negative data
3
DATA2+
positive data
4
GND
ground
5
VCC
sw5V supply
6
DATA1-
negative data
7
DATA1+
positive data
8
GND
ground
