73K324BL
CCITT V.22bis,V.23,V.22,V.21, Bell 212A
Single-Chip Modem w/ Integrated Hybrid
DATA SHEET
TONE REGISTER
D7
D6
D5
D4
D3
D2
D1
D0
TR
RXD
TRANSMIT TRANSMIT TRANSMIT DTMF
DTMF 2/
DTMF 1/
DTMF 0/
011
OUTPUT
CONTROL
GUARD
TONE
ANSWER
TONE
DTMF
3
4-WIRE EXTENDED ANSWER
FDX
OVER-
SPEED
GUARD
BIT
NAME
CONDITION
DESCRIPTION
D3 D2 D1 D0
D0 interacts with bits D6, D5, and D4 as shown
D3, D2,
D1, D0
DTMF 3,
2, 1, 0
0
1
0
1
0
1
0-
1
Programs 1 of 16 DTMF tone pairs that will be
transmitted when TX DTMF and TX enable bit (CR0, bit
D1) is set. Tone encoding is shown below:
KEYBOARD
EQUIVALENT
1
DTMF CODE
D3 D2 D1 D0
TONES
LOW
HIGH
0
0
0
1
697
1209
2
0
0
1
0
697
1336
3
4
5
6
7
8
9
0
*
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
697
770
770
770
852
852
852
941
941
941
697
770
852
941
1477
1209
1336
1477
1209
1336
1477
1336
1209
1477
1633
1633
1633
1633
#
A
B
C
D
D7
RXD Output
Control
0
1
Enables RXD pin. Receive data will be output on RXD.
Disables RXD pin. The RXD pin reverts to a high
impedance with internal weak pull-up resistor.
NOTE: DTMF0-DTMF2 should be set to an appropriate state after DTMF dialing to avoid unintended operation.
Page: 16 of 34
© 2005, 2008 TERIDIAN Semiconductor Corporation
Rev 6.1
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
