Motorola MVME712AM Manual Do Utilizador

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MVME712A/D3A-1
A
MODEM
General Description
The UDS 2242980 modem installed on the MVME712-13 or MVME712AM 
module provides full duplex operation over the 2-wire Public Switch 
Telephone Network (PSTN). The unit operates asynchronously at data rates of 
0 to 300, 600, 1200, or 2400 bps, and synchronously at data rates of 1200 and 
2400 bps. The modem uses both LSI and surface mount technologies to fit an 
auto dial 224 modem on just 9.6 square inches of board space. 
The modem provides transmit and receive filtering, adaptive equalization, 
and modulation and demodulation. Dual Tone Multi-Frequency (DTMF) tone 
encoding is also provided. Circuitry is included to aid you in telephone call 
progress monitoring for busy tone, reorder, and dial tone detection, and a 
buffered audio output is also provided. 
The modem provides command selection of either pulse or DTMF auto 
dialing. Also included is automatic answer and automatic speed adjustment to 
the speed of the originating modem. For applications requiring unattended 
operation, these features make the 2242980 card an ideal solution. The auto 
dialing command set is compatible with the popular ÒATÓ command set. 
The modem also includes integral diagnostic test features which aid in 
isolating communication faults to the phone line, the modem, or the data 
terminal equipment. Tests that may be performed include Analog Loopback, 
Analog Loopback Self Test, Digital Loopback, Remote Digital Loopback, and 
Remote Digital Loopback Self Test.