Low Power V.32 bis Modem
CMX869
Rx Mode Register b8-6: Modem Modes - Reserved, set to 000
Rx Mode Register b5-3: Rx Modem Data format
These three bits select the Rx modem USART operating mode.
b5
b4
b3
1
1
1
1
0
1
1
0
0
x
1
0
1
0
x
Rx Special modes
Rx Start-stop mode
Reserved, do not use
Reserved, do not use
Rx USART function disabled
Rx Mode Register b2-0: Rx Modem Data bits and Parity (Start-Stop modes)
In Start-stop mode these three bits select the number of data bits (plus any parity bit) in each
received character.
b2
b1
b0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
8 data bits + parity
8 data bits
7 data bits + parity
7 data bits
6 data bits + parity
6 data bits
5 data bits + parity
5 data bits
Rx Mode Register b2-0: Rx Modem Data bits and Parity (Special modes)
When b5-3 = 111 bits 2-0 select special receive modes as below:
b2
b1
b0
1
1
1
0
1
1
0
x
1
0
X
x
Synchronous, received bits transferred directly to Rx Data Register
Reserved, do not use.
Reserved, do not use.
Reserved, do not use.
Rx Mode Register b2-0: Tones Detect mode
In Tones Detect Mode (Rx Mode Register b15-12 = 0001) b8-3 should be set to 000000.
Bits 2-0 select the detector type.
b2
b1
b0
1
0
0
0
0
0
1
1
0
0
0
1
0
1
0
Programmable Tone Pair Detect
Call Progress Detect
2100, 2225Hz Answer Tone Detect
DTMF Detect
Disabled
© 2004 CML Microsystems Plc
26
D/869/4
CMLMICRO [ CML MICROCIRCUITS ]
