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3.2. AUX Board
3.2.1. Board Description
The AUX board contains a switching array and system of voice messages, controlled by
an independent processor system separated from the system bus. The AUX port is used for
making testing calls or recording voice messages. The input amplifier is designed for an electret
microphone, the output amplifier for 150ohm earphones. The board is designed on a 4-layer
PCB of the size of 160x100mm. A serial interface COM2, microtelephone or headphone
connector, and 5 board status indictors lead to the front panel.
PWR LED
Indicates board supply
Lights on
Switched on
Lights off
Switched off
Blinking
Board in sleep mode
INIT LED
Indicates board initialization or error status
Blinks
Indicates the initialization of the board
Lights on (45 sec)
Indicates duplication of the new firmware
Lights on (still)
Board initialization failure
AUX LED
indicates activity on AUX port
Lights on
Waiting for incoming call (AT!W…)
Blinks
Indicates the call through the testing AUX interface
Lights off
The testing interface on-hooked.
Rx LED
indicates reception via COM2
Tx LED
indicates transmission via COM2
3.2.2. COM2 Serial Port Parameters
The COM2 interface is used a supervision port for remote connection of a PC (terminal)
using ISDN or analog modem (also for loading voice message into the AUX board processor
memory). It allows to provide remote monitoring, configuration, tracing and firmware upgrade.
Transmission rate
57.6 kBd
Bit format
start, 8bit, stop (no parity)
Signals
complete 9-pin wiring
