73K222BL
V.22, V.21, Bell 212A, 103 Single-Chip
Modem with Integrated Hybrid
DATA SHEET
REGISTER DESCRIPTIONS
Four 8-bit internal registers are accessible for
control and status monitoring. The registers are
accessed in read or write operations by
addressing AD0, AD1 and AD2 lines. The address
lines are latched by ALE. Register CR0 controls
the method by which data is transferred over the
phone line. CR1 controls the interface between the
microprocessor and the 73K222BL internal state.
DR is the Detect Register, which provides an
indication of monitored modem status conditions.
TR, the Tone Control Register, controls the DTMF
generator, answer and guard tones and RXD
output gate used in the modem initial connect
sequence. All registers are read/write except for
DR, which is read only. Register control and status
bits are identified below:
REGISTER BIT SUMMARY
ADDRESS
DATA BIT NUMBER
REGISTER
AD2 - AD0
D7
D6
0
D5
D4
D3
D2
D1
D0
TRANSMIT
MODE
3
TRANSMIT
MODE
2
TRANSMIT
MODE
1
TRANSMIT
MODE
0
CONTROL
REGISTER
0
MODULATION
OPTION
TRANSMIT
ENABLE
ORIGINATE/
ANSWER
CR0
000
0 = 1200 BIT/S DPSK
1 = 600 BIT/S DPSK
0 = BELL 103 FSK
1 = V.21 FSK
0 = ANSWER
1 = ORIGINATE
0000 = PWR DOWN
0001 = INT SYNCH
0010 = EXT SYNCH
0011 = SLAVE SYNCH
0 = DISABLE
TXA OUTPUT
1 = ENABLE
TXA OUTPUT
0100 = ASYNCH 8 BITS/CHAR
0101 = ASYNCH 9 BITS/CHAR
0110 = ASYNCH 10 BITS/CHAR
0111 = ASYNCH 11 BITS/CHAR
1100 = FSK
TRANSMIT
PATTERN
1
TRANSMIT
PATTERN
0
ENABLE
DETECT
INTERRUPT
TEST
MODE
1
TEST
MODE
0
CONTROL
REGISTER
1
BYPASS
SCRAMBLER
CLK
CONTROL
001
RESET
CR1
00 = TX DATA
01 = TX ALTERNATE
10 = TX MARK
0 = DISABLE 0 = NORMAL
1 = ENABLE 1 = BYPASS
0 = XTAL
1 = 16 X DATA
0 = NORMAL
1 = RESET
00 = NORMAL
01 = ANALOG LOOPBACK
10 = REMOTE DIGITAL
LOOPBACK
SCRAMBLER RATE OUTPUT
AT CLK PIN IN
11 = TX SPACE
DPSK MODE
ONLY
11 = LOCAL DIGITAL
LOOPBACK
DETECT
REGISTER
RECEIVE
DATA
UNSCR.
MARKS
CARRIER
DETECT
ANSWER
TONE
CALL
PROGRESS
LONG
LOOP
X
X
DR
010
OUTPUTS
RECEIVED
0 = CONDITION NOT DETECTED
1 = CONDITION DETECTED
DATA STREAM
DTMF0/
GUARD/
ANSWER/
TONE
RXD
OUTPUT
CONTROL
TRANSMIT
GUARD/
TONE
TRANSMIT
ANSWER
TONE
TONE
CONTROL
REGISTER
TRANSMIT
DTMF
DTMF1/
OVERSPEED
011
DTMF3
DTMF2
TR
0 = Disable DTMF
1 = TX DTMF
RXD PIN
0 = NORMAL
1 = WEAK PULL-UP
0 = OFF
1 = ON
4 BIT CODE FOR 1 OF 16
DUAL TONE COMBINATIONS
0 = OFF
1 = ON
0 = 2225 Hz A.T.
1800 Hz G.T.
1 = 2100 Hz A.T.
500 Hz G.T.
ID
X
X
X
X
10
110
1
0
X
OH
REGISTER
00XX = 73K212AL, 322L, 321L
01XX = 73K221AL, 302L
10XX = 73K222AL, 222BL
1100 = 73K224L, 224BL
1110 = 73K324L, 324BL
X = Undefined, mask in software
0 = OH Relay driver open
1 = OH Open drain driver pulling low
NOTE: When a register containing reserved control bits is written into, the reserved bits must be
programmed as 0's.
X = Undefined, mask in software
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© 2005, 2008 TERIDIAN Semiconductor Corporation
Rev 7.2