73K224L-28IH TDK [TDK Electronics], 73K224L-28IH Datasheet - Page 15

• Manufacturer Part Number: 73K224L-28IH
• Description: V.22bis/V.22/V.21/ Bell 212A/Bell 103 Single-Chip Modem
• Manufacturer: TDK [TDK Electronics]

CONTROL REGISTER 2
BIT NO.
D4
D5
D6
D7
CONTROL REGISTER 3
BIT NO.
D3, D2,
D1,D0
D4
D5
D6
D7
CR3
101
CR2
100
TXDALT
D7
D7
0
Not used at this time
Not used at this time
TXCLK/RXCLK
Receive Gain
Transmit S1
TRISTATE
Attenuator
Transmit
TXDALT
Register
Call Init
Access
Special
SPEC REG
NAME
NAME
TRISTATE
TX/RXCLK
Boost
ACCESS
D6
D6
(continued)
CALL INIT
Spec. Reg. Bit D3=1
D3 D2
0
1
CONDITION
D5
CONDITION
D5
0
0
1
0
1
0
1
0
1
0
0
1
0
0
1
D1 D0
RECEIVE
ENABLE
0
1
BOOST
TRANSMIT
D4
0
1
D4
S1
V.22bis/V.22/V.21/Bell 212A/Bell 103
DESCRIPTION
The transmitter when placed in alternating mark/space
mode transmits 0101...... scrambled or not dependent on
the bypass scrambler bit.
When this bit is 1 and only when the transmitter is placed in
alternating mark/space mode by CR1 bits D7, D6, and in
DPSK or QAM, an unscrambled repetitive double dibit
pattern of 00 and 11 at 1200 bit/s (S1) is sent.
DEMOD mode: The DSP is setup to do demodulation and
pattern detection based on the various mode bits. Both
answer tones are detected in demod mode concurrently (wide
band detection); TR-D0 is ignored.
CALL INIT mode: The DSP decodes unscrambled mark,
answer tone and call progress tones.
Normal CR3 access.
Setting this bit and addressing CR3 allows access to the
SPECIAL REGISTER. See the SPECIAL REGISTER for
details.
Only write zero to this bit.
DESCRIPTION
Sets the attenuation level of the transmitted signal in 1dB
steps. The default (D3-D0=0100) is for a transmit level of –
10 dBm0 on the line with the recommended hybrid transmit
gain. 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
for internally generated noise when receiving weak signals.
The receive level detect signal and knowledge of the hybrid
and transmit attenuator setting will determine when boost
should be enabled.
Only write zero to this bit.
TXCLK and RXCLK are driven.
TXCLK and RXCLK are tri-stated.
Alternate TX data source. See Special Register.
15
TRANSMIT
ATTEN. 3
16WAY
D3
D3
TRANSMIT
ATTEN. 2
RESET
D2
DSP
D2
Single-Chip Modem
TRANSMIT
ATTEN. 1
INHIBIT
TRAIN
D1
D1
73K224L
EQUALIZER
TRANSMIT
ATTEN. 0
ENABLE
D0
D0