Avila Network Computer Operating Manual
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processor I2C bus. The I2C clock frequency is 0 to 400KHz. The I2C 7-bit base
address is 50 hex for writes and 51 hex for reads.
Fan Speed Controller
Fan speed control increases fan service life and decreases system acoustic
airflow noise. The GW2342 includes a Microchip TC653BE that controls the
speed of a fan based on temperature. This device keeps the fan off until the
GW2342 temperature reaches 35 degrees Celsius. The controller adjusts the fan
speed from 50% to 100% between 35 and 45 degrees Celsius.
Serial I/O
The GW2342 includes two RS232 serial I/O ports. One serial I/O port is available
through a 10-pin header and the other is available through a 9-pin female D-shell
connector. The serial ports are 16550-compliant UARTs with additional depth for
both the transmit and receive buffers. The interface supports transfer rates from
1200bps up to 120Kbps.
Digital I/O
The IXP processor includes a 16 bits of digital I/O. Some of these signals are
used for controlling and monitoring the status of devices local to the GW2342
and some of them are available on a 10-pin header for application use. The
function of each digital I/O signal is described in Section 2, Digital I/O Mapping.
USB
The GW2342 includes a version 1.1 Device Controller interface. The interface
operates as a half-duplex, slave-only device at a baud rate of 12Mbps. The
interface does not operate as a USB host. A standard USB Type B connector is
provided on the board.
JTAG Port
A JTAG debug port is available to facilitate program download directly into Flash
memory. See Section 2, JTAG Programming, for more information.
Status LED and Push Button Reset
The GW2342 includes a status LED and a push button reset. The LED is
connected to the digital I/O and can be controlled by software. See Section 2
Configuration and Installation for the mapping of the LED.
DC/DC Converter
A switching DC/DC converter supplies power to the GW2342. This allows the
board to support a wide input voltage range and low power operation. The
DC/DC has a minimum input voltage of 6VDC and a maximum of 28VDC.
DO
NOT EXCEED THE 28VDC INPUT MAXIMUM OR DAMAGE MAY OCCUR TO
THE BOARD
. Also note that if a power over Ethernet injector is used to power
the board, there will be voltage loss due to the resistance of the Ethernet cable.
This should be taken into account when sizing the voltage supply.
