Motorola MVME712B - Manual (Page 68)

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.