Low Power V.22 bis Modem
CMX868
1.5.10.7 Status Register
Status Register: 16-bit read-only.
C-BUS address $E6
Bits 13-0 of this register are cleared to 0 by a General Reset command, or when b7 (Reset) of the
General Control Register is 1.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit:
IRQ
RD
PF
See below for uses of these bits
The meanings of the Status Register bits 12-0 depend on whether the receive circuitry is in Modem or
Tones Detect mode.
Status Register bits:
Rx Modem modes
Rx Tones Detect modes
** IRQ
Mask bit
b15
b14
b13
b12
IRQ
Set to 1 on Ring Detect
Programming Flag bit. See 1.5.10.8
Set to 1 on Tx data ready.
b5
b4
b3
Cleared by write to Tx Data Register
Set to 1 on Tx data underflow.
Cleared by write to Tx Data Register
b11
b10
b3
b2
1 when energy is detected in Rx
modem signal band
1 when energy is detected in Call
Progress band or when both
programmable tones are detected
0
b9
1 when S1 pattern (double DPSK
dibit 00,11) is detected in DPSK or
QAM modes, or when ‘1010..’
pattern is detected in FSK modes
See following table
b1
b8
b7
0
b1
b1
See following table
1 when 2100Hz answer tone or the
second programmable tone is
detected
b6
b5
Set to 1 on Rx data ready.
Cleared by read from Rx Data
Register
Set to 1 on Rx data overflow.
Cleared by read from Rx Data
Register
1 when 2225Hz answer tone or the
first programmable tone is detected
b0
b0
1 when DTMFcode is detected
b4
b3
b2
b1
b0
Set to 1 on Rx framing error
Set to 1 on even Rx parity
QAM/DPSK Rx signal quality b2
QAM/DPSK Rx signal quality b1
QAM/DPSK Rx signal quality b0
or FSK frequency demodulator
output
0
-
-
-
-
-
Rx DTMF code b3, see table
Rx DTMF code b2
Rx DTMF code b1
Rx DTMF code b0
ã 2004 CML Microsystems Plc
29
D/868/9
CMLMICRO [ CML MICROCIRCUITS ]
