NAL RESEARCH CORPORATION A3LA-RM, Быстрый старт

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AL3A-RM Quick Start Guide Version A
Document Number: 451-93156-014A 10 of 18
Table 1: Pin Assignment for the Multi-interface Connector
Pin # Signal Description Interface
22 CTS RS232 clear to send RS232 Data
23 SIGNAL GND Signal ground, 0 V signal reference and return GND
24 DA_RX PCM digital audio input Digital Audio
25 SIGNAL GND Signal ground, 0 V signal reference and return GND
2.1.1 RS232 D
ATA
I
NTERFACE
(S
TANDARD
9-W
IRE
C
ONFIGURATION
)
The A3LA-RM supports a standard RS232 data interface to a DTE incorporating hardware
handshaking and flow control. The RS232 data interface comprises eight standard RS232 data,
control, and status signals, plus a ground-level signal reference, as shown in Table 1 . This
interface allows a connected DTE to utilize the A3LA-RM’s modem functionality through a set of
AT commands (see SatTerm Software Manual Version A).
2.1.2 DC P
OWER
I
NPUT
The DC power input is through pin 4 & 16 (EXT_B+) and pins 3 & 17 (EXT_GND). Note that two
pins are provided for the external DC input and two pins are also provided for the associated
external ground input. This is done to distribute the current across two wires, and therefore all
four pins should be utilized in the external power connection.
2.1.3 P
OWER
O
N
/O
FF
C
ONTROL
With the EXT_ON_OFF pin left unconnected, the A3LA-RM automatically turns on or off when
external DC power is applied or removed. Prior to turning the A3LA-RM off, issue command
AT*P0 to ensure all memory write activity is completed.
2.2 A
UDIO
I
NTERFACE
The A3LA-RM supports both digital and analog audio Input/output (I/O). The digital audio is in
PCM format. In such format, digital audio cannot travel far (less than one foot); this is why the
analog is chosen for the A3LA-RM audio handset (see Figure 2 ).