73K324L-IGT ETC [List of Unclassifed Manufacturers], 73K324L-IGT Datasheet - Page 15

• Manufacturer Part Number: 73K324L-IGT
• Description: CCITT V.22bis, V.22, V.21, V.23, Bell 212A Single-Chip Modem
• Manufacturer: ETC [List of Unclassifed Manufacturers]

CONTROL REGISTER 3
BIT NO.
D3, D2,
D1,D0
D4
D5
D6
D7
ID REGISTER
SPECIAL REGISTER
BIT NO.
D7, D4, D0
D6
D5
CR3
101
101
SR
TXDALT
D7
D7
0
TXCLK/RXCLK
NAME
TXBAUD
CLK
RXUNDSCR
DATA
Gain Boost
Attenuator
TX/RXCLK
TRISTATE
Not Used
Transmit
TXDALT
Receive
(18 dB)
Tristate
NAME
TXBAUD
CLOCK
D6
D6
DESCRIPTION
NOT USED AT THIS TIME. Only write ZEROs to these bits.
TXBAUD clock is the transmit baud-synchronous clock that can be used to
synchronize the input of arbitrary quad/di-bit patterns. The rising edge of
TXBAUD signals the latching of a baud-worth of data internally. Synchronous
data to be entered via the TXDALT bit, CR3 bit D7, should have data
transitions that start 1/2 bit period delayed from the TXBAUD clock edges.
This bit outputs the data received before going to the descrambler. This is
useful for sending special unscrambled patterns that can be used for signaling.
Spec. Reg. bit D3=1
D3
0
1
D5
0
RXUN-
CONDITION
DSCR
DATA
D5
D2 D1 D0
0
1
CCITT V.22bis, V.22, V.21, V.23, Bell 212A
0
1
0
0
1
RECEIVE
0
1
ENABLE
BOOST
D4
0-
1
D4
0
15
DESCRIPTION
Sets the attenuation level of the transmitted signal in 1 dB
steps. The default (D3-D0=0100) is for a transmit level of
–10 dBm0. The total range is 16 dB.
18 dB receive front end boost is not used.
Boost is in the path. This boost does not change
reference levels. It is used to extend dynamic range by
compensating
receiving weak signals. The receive level detect signal
and knowledge of the hybrid and transmit attenuator
setting will determine when boost should be enabled.
Not used. Only write zeros this location.
TXCLK, RXCLK outputs driven
TXCLK, RXCLK outputs in Tristate mode
Alternate TX data source. See Special Register.
TRANSMIT
ATTEN.
D3
SOURCE
3
TXD
D3
for
TRANSMIT
ATTEN.
SELECT1
QUALITY
internally
D2
SIGNAL
LEVEL
2
D2
Single-Chip Modem
TRANSMIT
generated
ATTEN.
SELECT0
QUALITY
SIGNAL
LEVEL
D1
1
D1
73K324L
noise
TRANSMIT
ATTEN.
D0
D0
0
0
when