V.22 bis Modem with AT Commands
CMX866
Note that if the CMX866 is in Data Transfer mode, an escape sequence must be
issued (+++) to return the CMX866 to Command mode before this loopback
connection command can be given. The AT&T0, AT&T3 and AT&T6 commands
can only be issued when off-hook. The AT&T4 and AT&T5 commands can be
issued when either on-hook or off-hook.
&V
Current Configuration
Returns the current CMX866 configuration by reading the S-Registers. The register
data is output on the RXD pin in the form (where xxx is decimal data):
S00: xxx S01: xxx S02: xxx S03: xxx S04: xxx S05: xxx S06: xxx S07: xxx S08: xxx S09: xxx<CR>
S10: xxx S11: xxx S12: xxx S13: xxx S14: xxx S15: xxx S16: xxx S17: xxx S18: xxx S19: xxx<CR>
S20: xxx S21: xxx S22: xxx S23: xxx S24: xxx S25: xxx S26: xxx S27: xxx S28: xxx S29: xxx<CR>
This register data is also available in hexadecimal form, by setting bit 4 of S14
register.
Syntax: AT&V<CR>
&Zn
Sleep States
Instructs the CMX866 to enter one of the following sleep states:
Syntax: AT&Zn<CR>
Modifier Usage
n=0 'Zero-Power' state.
n=1 Powersave state.
The 'Zero-Power' state stops the crystal oscillator and removes power from the
VBIAS pin, for minimum power consumption. It takes about 30ms for the CMX866
to become fully operational from the 'Zero-Power' state. However, the crystal
oscillator only takes about 1.4ms to become stable, so commands which do not
require the analogue parts of the DSP to be stable (VBIAS at ½VDD) can be given to
the on-chip µController after this time.
The Powersave state stops the internal clock distribution, but retains power to the
crystal oscillator and VBIAS circuit. Consequently, the CMX866 can become
operational from this state in about 10µs.
To enter either sleep state, the DTRN pin must already be inactive (high) and the
RD and RT pins inactive (low).
ã 2004 CML Microsystems Plc
24
D/866/4
CMLMICRO [ CML MICROCIRCUITS ]
