Sharp FO-1470 Service Manual page 58

UX-510UA
FO-1470U
(4) Modem (SCE114/20415) block
INTRODUCTION
The CONEXANT SCE114 modem is a synchronous 14400 bits per sec-
ond (bps) half-duplex modem with error detection and DTMF reception.
It has low power consumption and requires +5V and +3.3V DC power
supply.
The modem can operate over the public switched telephone network
(PSTN) through line terminations provided by a data access arrange-
ment (DAA).
The SCE114 is designed for use in Group 3 facsimile machines.
The modem satisfies the requirements specified in ITU-T recommenda-
tions V.17, V.29, V.27 ter, V.21 Channel 2 and T.4, and meets the binary
signaling requirements of T.30.
The modem can operate at 14400, 12000, 9600, 7200, 4800, 2400, or
300 bps, and also includes the V.27 ter short training sequence option.
The modem can also perform HDLC framing according to T.30 at 9600,
7200, 4800, 2400, or 300 bps.
The modem features a programmable DTMF receiver and three pro-
grammable tone detectors which operate concurrently with the V.21
channel 2 receiver.
The voice mode allows the host computer to efficiently transmit and
receive audio signals and messages.
DSP
SA1CLK
IA1CLK
IACLK
SR1IO
SR4OUT
SR3IN
GPO0
SCE114
TYPICAL EXTERNAL HYBRID
TYPICAL MICROPHONE
CIRCUIT
TYPICAL SPEAKER CIRCUIT
IA
FSYNC
ICLK
MCLK
MODE 0
CTRLSIN
MODE1
SIN
SOUT
POR
LINEIN
LINEO
MICIN+
MICIN–
SPKRO+
SPKRO–
Connections for MODE 0
and MODE 1 pins are
shown for a Line IA.
Fig. 5
FEATURES
•
Group 3 facsimile transmission/reception
- ITU-T V.17, V.33, V.29, V.27 ter, T.30, V.21 Channel 2, T.4
- ITU-T V.17 and V.27 ter short train
- HDLC framing at all speeds
- Receive dynamic range: 0 dBm to -43 dBm
- Automatic adaptive equalization
- Fixed and programmable digital compromise equalization
- DTMF detect and tone detect
- ITU-T V.21 Channel 2 FSK 7E Flag Detect
- Ring detector
- Programmable transmits level
- Programmable single/dual tone transmission
•
V.23 and Type I Caller ID
- Full-duplex modes:
TX = 75 bps. RX = 1200 bps
TX = 1200 bps. RX = 75 bps
- Half-duplex mode:
TX = RX = 1200 bps
- Serial and parallel data modes
- Programmable parallel data mode
- 5, 6, 7 or 8 data bits
- 1 or 2 Stop bits
- Mark, Space, Even, or Odd Parity
- Break function
- Transmitter squelch
- Compromise equalizer
•
Programmable interface memory interrupt
•
Eight General Purpose Input (GPI) and eight General Purpose Out-
put (GPO) pins for host assignment
•
DTE interface: two alternate ports
- Selectable microprocessor bus (6500 or 8085)
GND
- ITU-T V.24 (EIA/TIA-232-E compatible) interface
•
TTL and CMOS compatible
•
3.3V/5V operation
•
Power consumption
- Operating Mode: 200 mW (Basic), 275 mW (-V option). 300 mW
(-VS option)
- Sleep Mode: 1 ma (Basic. -V option and -VS option)
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