Rockwell RFX144V24-S23, Designer'S Manual

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RFX144V24-S23 and RFX96V24-S23 Modem Designer’s Guide
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Table 3-1. Interface Memory Bit Definitions (Cont'd)
Mnemonic Location Default Name/Description
SCR1 0C:4 – Scrambled Ones. When the modem is configured as a high speed transmitter, status bit SCR1 = 1
indicates scrambled ones are being sent. When SCR1 = 0, scrambled ones are not being sent.
When the modem is configured as a high speed receiver, status bit SCR1 = 1 indicates scrambled ones
are being received. When SCR1 = 0, scrambled ones are not being received.
SETUP 1F:0 0 Setup. Control bit SETUP must be set to a 1 by the host after the host writes a configuration code into
the CONF bits (06:0-7) or changes any of bits 0 through 6 in register 07 (07:0-6). This informs the
modem to implement the configuration change. The modem resets the SETUP bit to a 0 when the
configuration change request is recognized.
SHPR 1D:7 0 Short Train Rate Sequence. When control bit SHPR is a 1, the V.17/V.33 rate sequence is included in
the short training sequence, which extends the training by 64 bauds.
SHTR 07:4 0 Short Train Mode. When control bit SHTR is a 1 and the modem is configured as a high speed receiver
(see CONF), the modem will perform a short training sequence. A successful long train at the same
data rate must precede its short train. (Note: For V.17, a successful long train at any data rate must
precede its short train.) The setting of the SHTR bit must be followed by the setting of the SETUP bit.
The EQSV bit must be set and the EQFZ bit may optionally be set for Short Train operation.
SLOW 14:1 0 Slower by 50% Playback Speed. When control bit SLOW is a 1 and the FAST50, FAST33, and NORM
control bits are reset, playback time is 150% of normal playback time. SLOW must be reset when
another speed is selected. (Voice Codec Mode)
SP/HS 0E:4 1 Speakerphone/Handset Switch. In speakerphone mode, when control bit SP/HS is a 1,
microphone/speaker operation is enabled; when SP/HS is a 0, handset in place of microphone/speaker
is assumed for handset operation.
SQEXT 07:2 0 Squelch Extend. Control bit SQEXT determines the length of time the modem receiver is inhibited from
receiving any signal after transmitter turn-off. The length of time is either 20 ms (SQEXT = 0) or 140 ms
(SQEXT = 1). The setting of the SQEXT bit must be followed by the setting of the SETUP bit to become
active.
STB 14:2 0 Stop Bit Number. When control bit STB is reset, one stop bit is selected; when set, two stop bits are
selected. (V.23)
TBUFFER 12:0-7 00 Transmit Data Buffer. In V.23 mode (CONF = 24h), the host conveys output data to the transmitter in
the parallel mode by writing a data byte to the TBUFFER. The data is transmitted bit 0 first.
TDBE 18:1 1 Transmit Data Buffer Empty. When set, status bit TDBE signifies that the modem has read TBUFFER
(register 12) and the host can write new data into TBUFFER. This condition can also cause an IRQ to
be asserted using the programmable interrupt. The host must clear the bit to transmit data. (V.23)
TDIS 07:6 0 Training Disable. When control bit TDIS is a 1, the modem as a receiver is prevented from recognizing
a training sequence and entering the training state; as a transmitter the modem will not transmit the
training sequence when the ~RTS pin or RTSP bit is activated.
TND8K 14:7 - Tone Detector 8 kHz Sample Rate. In the voice/audio codec modes (CONF = 90h, 92h, 94h or 98h),
control bit TND8K selects the tone detector sample rate (0 = 4000 Hz; 1 = 8000 Hz). TND8K defaults to
a 0 in Voice Codec Modes (CONF = 90h or 98h) and to a 1 in the Audio Codec Modes (CONF = 92h or
94h). In Voice Codec mode during room monitor operation, set TNDK8 to 0 when encoding a message.
TONEIE 0F:6 0 IIA Tone Enable. In speakerphone mode, control bit TONEIE enables (TONEIE = 1) or disables
(TONEIE = 0) tone to the IIA DAC while in tone transmit mode (TTONEE = 1).
TONEXE 0F:5 0 XIA Tone Enable. In speakerphone mode, control bit TONEXE enables (TONEXE = 1) or disables
(TONEXE = 0) tone to the XIA DAC while in tone transmit mode (TTONEE = 1).