3
AT Commands
(continued)
&Ln
Leased-Line Mode
&L0
Disables leased-line operation.
&L1
2-wire originate leased-line operation.
&L2
4-wire originate leased-line operation.
&L3
2-wire answer leased-line operation.
&L4
4-wire answer leased-line operation.
&Mn,&Qn Async/Sync Mode and DTE Dialer Type
&M0,&Q0 Modem operates in Asynchronous
mode and uses AT command protocol.
&M1,&Q1 Modem operates in Synchronous mode
and uses AT command protocol.
&M2,&Q2 Modem operates in Synchronous mode
and dials telephone number stored in
directory location 1 when DTR signal
turns Off and then ON.
&M3,&Q3 Modem operates in Synchronous mode
and uses AT command protocol.
&Q4
Modem operates in Asynchronous mode
and uses AT Command protocol; Hayes
AutoSync is enabled.
&M231, &Q231 Modem operates in Asynchronous
mode; the DTE Dialer Type is disabled.
&M232, &Q232 Modem operates in Asynchronous
mode; V.25bis Async dialing is enabled.
&M233, &Q233 Modem operates in Synchronous
mode; V.25 Bisync dialing is enabled.
&M234, &Q234 Modem operates in Synchronous
mode; V.25bis HDLC dialing is enabled.
&M235, &Q235 Modem operates in Asynchronous
mode; AT&T Exclusive dialing is enabled.
&M236, &Q236 Modem operates in Synchronous
mode; the DTE Dialer Type is disabled.
&Rn
RTS Action
&R0
Standard RS232. RTS action is
controlled by DTE.
&R1
Ignores RTS. Modem ignores RTS
signal and treats it as always ON.
&R2
Simulated Control Carrier. State of RTS
follows state of LSD.
&Sn
DSR Control
&S0
Forced On. Forces DSR signal ON.
&S1
Standard RS232. Modem controls DSR
signal.
&S2
Wink When Disc. DSR signal turns Off
for approximately 1 to 2 seconds upon
disconnecting.
&S3
Follows DTR. Modem sends DSR to DTE
when it receives DTR from DTE.
&S4
On Early. DSR is Off when modem is in
idle state. DSR goes ON when modem
enters Data mode.
&S5
Delay to Data. DSR does not turn ON
until the modem enters Data mode.
&S6
Dial Backup toggle.
AT Commands
(continued)
&Tn
Tests
&T0
Stops any test in progress.
&T1
Starts a Local Analog Loopback test
(V.54, L3).
&T2
Transmits and receives a 511 BERT
pattern.
&T3
Starts a Local Digital Loopback test.
&T4
Accepts request from remote modem for
a Remote Digital Loopback test.
&T5
Denies request from remote modem for a
Remote Digital Loopback test.
&T6
Starts a Remote Digital Loopback test
(V.54, type L2).
&T7
Starts a Remote Digital Loopback test
with a Pattern (V.54, type L2).
&T8
Starts a Local Analog Loopback test
with a Pattern (V.54, type L3).
&T9
Starts a self-test.
&Vn
View Configuration Options
&V0
Displays Active (Operating) configuration
options.
&V1
Displays Active (Saved) configuration
options.
&V2
Displays Customer 1 configuration
options.
&V3
Displays Customer 2 configuration
options.
&V4
Displays telephone numbers stored in
directory locations 1–10.
&Wn
Write (Save to Memory)
&W0
Saves current configuration options in
Active (Operating) to Active (Saved).
&W1
Saves current configuration options in
Active (Operating) to Customer 1.
&W2
Saves current configuration options in
Active (Operating) to Customer 2.
&Xn
Transmit Clock Source
&X0
Modem provides internal clock source
for synchronous data (Pin 15).
&X1
Modem uses external source (Pin 24) for
clock for synchronous data.
&X2
Modem uses received signal as clock
source for synchronous data.
&Z
n=x
Modem stores telephone number
x (and
any dial modifiers) in directory location
n
(1–10). For example, the command
AT&Z1=555-1234 stores the number
5551234 in directory location 1. To clear
a telephone number from a memory
location, issue &Z
n=x without entering a
telephone number.
\
An
Maximum Frame Size
\A0
64
\A1
128
\A2
192
\A3
256
\A4
32
\A5
16
