FM214 ETC [List of Unclassifed Manufacturers], FM214 Datasheet - Page 4

• Manufacturer Part Number: FM214
• Description: 9600/14400 BPS MONOFAX MODEM FAMILY
• Manufacturer: ETC [List of Unclassifed Manufacturers]

Technical Specifications
Configurations, Symbol Rates and Data Rates
The selectable modem configurations, along with the
corresponding symbol (baud) rates and data rates, are
listed in Table 2.
Scrambler/Descrambler
The modem incorporates a self-synchronizing
scrambler/descrambler in accordance with ITU-T V.33,
V.17, V.29, and V.27 ter recommendations, depending
upon the selected configuration.
Data Encoding
The data encoding conforms to ITU-T
recommendations V.33, V.17, V.29, V.27 ter, V.21
Channel 2, and V.23.
Fixed Digital Cable Compromise Equalizer
Compromise equalization can improve performance
when operating over low quality lines. The modem has
a selectable fixed digital compromise cable equalizer
in the high speed receive and transmit data path.
Transmitted Data Spectrum
The transmitted data spectrum is shaped in the
baseband by an excess bandwidth finite impulse
response (FIR) filter with the following characteristics:
When operating at 2400 baud, the transmitted
spectrum is shaped by a square root of 20% raised
cosine filter.
When operating at 1600 baud, the transmitted
spectrum is shaped by a square root of 50% raised
cosine filter.
When operating at 1200 baud, the transmitted
spectrum is shaped by a square root of 90% raised
cosine filter.
The out-of-band transmitter energy levels in the 4 - 50
kHz frequency range are below -55.0 dBm.
Transmit Level
The transmitter output level is programmable in the
DSP RAM from 0 dBm to -15.0 dBm and is accurate to
digitally scaling the output to the transmitter's digital-
to-analog converter.
Turn-on Sequence
Transmitter turn-on sequence times are shown in
Table 3.
4
1.0 dB. The modem adjusts the output level by
Receive Dynamic Range
The receiver satisfies PSTN performance
requirements for received line signal levels from 0
dBm to -43 dBm measured at the Receiver Analog
Input (RXA) input. An external input buffer must be
supplied between RXA and LINEIN.
The default values of the programmable Received
Line Signal Detector (RLSD#) turn-on and turn-off
threshold levels are -43 dBm and -48 dBm,
respectively. The RLSD# threshold levels can be
programmed over the following range:
Automatic Adaptive Equalizer
An adaptive equalizer in ITU-T V.33, V.17, V.29 and
V.27ter modes compensates for transmission line
amplitude and group delay distortion.
Receiver Timing
The timing recovery circuit can track a 0.01%
frequency error in the associated transmit timing
source.
Carrier Recovery
The carrier recovery circuit can track a 7 Hz
frequency offset in the received carrier.
Turn-off Sequence
Transmitter turn-off sequence times are shown in
Table 4.
Clamping
Received Data (RXD) is clamped to a constant mark
whenever RLSD# is off.
V.23 Full-Duplex Features
The modem can transmit and detect Break signals
(continuous Space).
The Mark and Space frequencies are 1300 and 2100
Hz, respectively, for 1200 bps, and 390 and 450 Hz,
respectively, for 75 bps.
Additional features include an optional host
programmable Receive Compromise Equalizer for
V.23 1200 bps reception and Caller ID mode.
Default transmitter turn-on/turn-off sequence times are
10.5 ms (RTS On to CTS On) and 2.2 ms (RTS Off to
CTS Off).
Turn on: -10 dBm to -47 dBm
Turn off: -10 dBm to -52 dBm
MD205