Links to other Reference Manual pages:
This chapter discusses the following topics:
Direct Command
AT Commands
MNP 10 Commands
Fax Class 1 Commands
AT+
Commands/V.25ter Operation Controls
This chapter describes your modem's data mode commands. Each of
these commands should be preceded by AT, except for the A/, AT
command, and Escape Code.
Direct Command A/ Re-execute command.
AT Commands
A Go off-hook and attempt to answer a call. B0 Select
V.22 connection at 1200 bps. B1 Select Bell 212A
connection at 1200 bps. C1 Return OK message. Dn Dial
modifier. E0 Turn off command echo. E1 Turn on
command echo. F0 Select auto-detect mode (equivalent to
N1). (RC144) F1 Select V.21 or Bell 103. (RC144) F2
Reserved. (RC144) F3 Select V.23 line modulation. (RC144)
F4 Select V.22 or Bell 212A 1200 bps line speed. (RC144) F5
Select V.22 bis line modulation. (RC144) F6 Select V.32
bis or V.32 4800 line modulation. (RC144) F7 Select V.32
bis 7200 line modulation. (RC144) F8 Select V.32 bis or
V.32 9600 line modulation. (RC144) F9 Select V.32 bis
12000 line modulation. (RC144) F10 Select V.32 bis 14400
line modulation. (RC144) H0 Initiate a hang-up sequence.
H1 If on-hook, go off-hook and enter command mode. I0
Report product code. I1 Report pre-computed checksum. I2
Report OK. I3 Report firmware revision, model, and
interface type. I4 Report response programmed by an OEM.
I5 Report the country code parameter. I6 Report modem
data pump model and code revision. I7 Reports the DAA code
(W-class models only). L0 Set low computer speaker volume.
L1 Set low computer speaker volume. L2 Set medium computer
speaker volume. L3 Set high computer speaker volume. M0 Turn
computer speaker off. M1 Turn computer speaker on during
handshaking and turn speaker off while receiving carrier. M2 Turn
computer speaker on during handshaking and while receiving
carrier. M3 Turn computer speaker off during dialing and
receiving carrier and turn computer speaker on during answering.
N0 Turn off automode detection. N1 Turn on automode
detection. O0 Go on-line. O1 Go on-line and
initiate a retrain sequence. P Force pulse dialing. Q0
Allow result codes to DTE. Q1 Inhibit result codes to DTE.
Sn Select S-Register as default. Sn? Return the value
of S-Register n. =v Set default S-Register to value v.
? Return the value of default S-Register. T Force DTMF
dialing. V0 Report short form (terse) result codes. V1
Report long form (verbose) result codes. W0 Report DTE
speed in EC mode. W1 Report line speed, EC protocol and
DTE speed. W2 Report DCE speed in EC mode. X0
Report basic call progress result codes, i.e., OK, CONNECT,
RING, NO CARRIER (also, for busy, if enabled, and dial tone not
detected), NO ANSWER and ERROR. X1 Report basic call progress
result codes and connections speeds (OK, CONNECT, RING, NO
CARRIER (also, for busy, if enabled, and dial tone not detected),
NO ANSWER, CONNECT XXXX, and ERROR. X2 Report basic call
progress result codes and connections speeds, i.e., OK,
CONNECT, RING, NO CARRIER (also, for busy, if enabled, and dial
tone not detected), NO ANSWER, CONNECT XXXX, and ERROR. X3
Report basic call progress result codes and connection rate,
i.e., OK, CONNECT, RING, NO CARRIER, NO ANSWER, CONNECT XXXX,
BUSY, and ERROR. X4 Report all call progress result codes and
connection rate, i.e., OK, CONNECT, RING, NO CARRIER, NO
ANSWER, CONNECT XXXX, BUSY, NO DIAL TONE and ERROR. Y0 Disable
long space disconnect before on-hook. Y1 Enable long space
disconnect before on-hook. Z0 Restore stored profile 0
after warm reset. Z1 Restore stored profile 1 after warm
reset. &C0 Force RLSD active regardless of the carrier
state. &C1 Allow RLSD to follow the carrier state.
&D0 Interpret DTR ON-to-OFF transition per &Qn:
&Q0, &Q5, &Q6 The modem ignores DTR. &D1
Interpret DTR ON-to-OFF transition per &Qn: &Q0,
&Q5, &Q6 Asynchronous escape. &D2 Interpret DTR
ON-to-OFF transition per &Qn: &Q0 through &Q6 The
modem hangs up. &D3 Interpret DTR ON-to-OFF transition per
&Qn:. &Q0, &Q5, &Q6 The modem performs soft
reset. &F0 Restore factory configuration 0. &F1
Restore factory configuration 1. &G0 Disable guard
tone. &G1 Disable guard tone. &G2 Enable
1800 Hz guard tone. &J0 Set S-Register response only
for compatibility. &J1 Set S-Register response only
for compatibility. &K0 Disable DTE/DCE flow control.
&K3 Enable RTS/CTS DTE/DCE flow control. &K4
Enable XON/XOFF DTE/DCE flow control. &K5 Enable
transparent XON/XOFF flow control. &K6 Enable both
RTS/CTS and XON/XOFF flow control. &L0 Select dial up
line operation. &M0 Select direct asynchronous mode.
&P0 Set 10 pps pulse dial with 39%/61% make/break. &P1
Set 10 pps pulse dial with 33%/67% make/break. &P2 Set
20 pps pulse dial with 39%/61% make/break. &P3 Set 20
pps pulse dial with 33%/67% make/break. &Q0 Select
direct asynchronous mode. &Q5 Modem negotiates an
error corrected link. &Q6 Select asynchronous
operation in normal mode. &R0 CTS tracks RTS (async)
or acts per V.25 (sync). &R1 CTS is always active.
&S0 DSR is always active. &S1 DSR acts per
V.25. &T0 Terminate any test in progress. &T4
Allow remote digital loopback. &T5 Disallow remote
digital loopback request. &V Display current
configurations. &V1 Diagnostics: &W0 Store
the active profile in NVRAM profile 0. &W1 Store the
active profile in NVRAM profile 1. &X0 Select internal
timing for the transmit clock. &X1 Select external
timing for the transmit clock. &X2 Select slave
receive timing for the transmit clock. &Y0 Recall
stored profile 0 upon power up. &Y1 Recall stored
profile 1 upon power up. &Zn=x Store dial string x (to
34) to location n (0 to 3). %E0 Disable line quality
monitor and auto retrain. %E1 Enable line quality monitor
and auto retrain. %E2 Enable line quality monitor and
fallback/fall forward. %G1 Monitor line quality and
automatically request a rate renegotiation if line conditions are
bad (default). %L Return received line signal level. %Q
Report the line signal quality. %Un Control u-law/A-law
settings (n=0 for u-law; 1 for A-law). * Serial interface
operation only. \Kn Controls break handling during three
states:
When modem receives a break from the DTE: \K0,2,4 Enter
on-line command mode, no break sent to the remote modem. \K1
Clear buffers and send break to remote modem. \K3 Send
break to remote modem immediately. \K5 Send break to
remote modem in sequence with transmitted data.
When modem receives \B in on-line command state: \K0,1
Clear buffers and send break to remote modem. \K2,3 Send
break to remote modem immediately. \K4,5 Send break to
remote modem in sequence with transmitted data.
When modem receives break from the remote modem: \K0,1
Clear data buffers and send break to DTE. \K2,3 Send a
break immediately to DTE. \K4,5 Send a break with received
data to the DTE. \N0 Select normal speed buffered mode.
\N1 Select direct mode. \N2 Select reliable link mode.
\N3 Select auto reliable mode. \N4 Force LAPM mode.
\N5 Force MNP mode. \V0 Connect messages are controlled
by the command settings X, W, and S95. \V1 Connect
messages are displayed in the single line format.
MNP 10 Commands
-K0 Disable MNP 10 extended services. -K1 Enable MNP 10
extended services. -K2 Enable MNP 10 extended services
detection only. -SEC=0 Disable MNP10-EC. -SEC=1,[<tx
level>] Enable MNP10-EC and set transmit level <tx
level> 0 to 30 (0 dBm to -30 dBm).
Fax Class 1 Commands
+FCLASS=n Service class. +FAE=n Data/fax auto answer
+FRH=n Receive data with HDLC framing. +FRM=n Receive
data. +FRS=n Receive silence. +FTH=n Transmit data
with HDLC framing. +FTM=n Transmit data. +FTS=n
Stop transmission and wait.
AT+ Commands/V.25ter
Operation Controls
+DS Data Compression This command
controls the V.42bis data compression function if provided in the
DCE.
The format for AT+DS is:
AT+DS=<direction>,<compression_negotiation>, <max_dict>, <max_string>
The Direction parameter specifies the desired direction(s) of operation of the data compression function from the DTE point of view. The Direction parameters are:
Direction | |
---|---|
0 | Negotiated. No compression (V.42bis P0=0) |
1 | Transmit only |
2 | Receive only |
3 | Both directions, accept any direction (V.42bis P0=11) Default. |
The compression_negotiation parameter specifies whether or not the DCE should continue to operate if the desired result is not obtained. The compression_negotiation parameters are:
compression_negotiation | |
---|---|
0 | Do not disconnect if V.42 bis is not negotiated by the remote DCE as specified in the Direction parameter. |
1 | Disconnection if V.42 bis is not negotiated by the remote DCE as specified in the Direction parameter. Default. |
The max_dict parameter specifies the maximum number of dictionary entries which should be negotiated. This parameter may be used by the DTE to limit the codeword size transmitted, based on its knowledge on the nature of the data to be transmitted. The max_dict parameter has a range of 512 to 65535.
The max_string parameter specifies the maximum string length to be negotiated (V.42bis P2). The max_string parameter has a range of 6 to 250. The default is 6.
+ES Error Control Selection This command contols the manner of operation of the V.42 protocol in the DCE (if present).
The format for AT+ES is:
AT+ES=<orig_rqst>, <orig_fbk>, <ans_fbk>
The orig_rqst parameter specifies the initial requested mode of operation when the DCE is operating as the originator. The orig_rqst parameters are:
orig_rqst | |
---|---|
0 | Direct mode |
1 | Initiate call with Buffered mode only |
2 | Initiate V.42 without Detection Phase. If V.8 is in use, this is a request to disable V.42 Detection Phase. |
3 | Initiate V.42 with Detection Phase. Default. |
4 | Initiate Alternative Protocol. |
The orig_fbk parameter specifies the acceptable fallback mode of operation when the DCE is operating as the originator. The orig_fbk parameters are:
orig_fbk | |
---|---|
0 | Error control optional (either LAPM or Alternative acceptable); if error control is not established, maintain DTE-DCE data rate and use buffered mode with flow control during non-error-control operation. Default. |
1 | Error control optional (either LAPM or Alternative acceptable); if error control is not established, change DTE-DCE data rate to match line rate and use Direct mode. |
2 | Error control optional (either LAPM or Alternative acceptable); if error control is not established, disconnect. |
3 | Error control optional (only LAPM acceptable); if error control is not established, disconnect. |
4 | Error control required (only Alternative protocol acceptable); if error control is not established, disconnect. |
The ans_fbk parameter specifies the acceptable fallback mode of operation when the DCE is operating as the answerer. The ans_fbk parameters are:
ans_fbk | |
---|---|
0 | Direct Mode |
1 | Error control disabled, use Buffered mode |
2 | Error control optional (either LAPM or Alternative acceptable); if error control is not established, maintain DTE-DCE data rate and use local buffering and flow control during non-error-control operation. Default |
3 | Error control optional (either LAPM or Alternative acceptable); if error control is not established, change DTE-DCE data rate to match line rate and use Direct mode. |
4 | Error control optional (either LAPM or Alternative acceptable); if error control is not established, disconnect. |
5 | Error control optional (only LAPM acceptable); if error control is not established, disconnect. |
6 | Error control required (only Alternative protocol acceptable); if error control is not established, disconnect. |
+ES V.80 Synchronous Access Mode Configuration To enable, use AT+ES=6 (Originator), AT+ES=,,8 (Receiver.) The modem can be issued T+ES=6,,8 which will cover both of the above commands. This configures the modem to initiate Synchronous Access Mode when connection is completed and Data State is entered.
+ESA Synchronous Access Mode Configuration This command is used to control the manner of operation of the Synchronous Access Mode in the DCE (if present). The format for AT+ESA is:
AT+ESA=<trans_idle>,<framed_idle>,<framed_un_ov>,<hd_auto>,<crc_type>,<nrzi_en>, <syn1>, <syn2>
The trans_idle parameter specifies the bit sequence transmitted by the DCE when a transmit data buffer underrun condition occurs. This is while operating in Transparent sub-Mode. The trans_idle parameters are:
trans_idle | |
---|---|
0 | In Transparent sub-Mode, DCE transmit 8 bit SYN sequence on idle. DCE receiver does not hunt for synchronization sequence. Default. |
1 | In Transparent sub-Mode, DCE transmit 8 bit SYN sequence on idle. DCE receiver hunts for 8 bit SYN sequence. |
2 | In Transparent sub-Mode, DCE transmit 16 bit SYN sequence on idle. DCE receiver hunts for 16 bit SYN sequence. |
The framed_idle parameter specifies the bit sequence transmitted by the DCE when a transmit data buffer underrun condition occurs immediately after a flag. This is while operating in Framed sub-Mode. The framed_idle parameters are:
framed_idle | |
---|---|
0 | In Framed sub-Mode, DCE transmits HDLC flags on idle. Default. |
1 | In Framed sub-Mode, DCE transmits marks (ones) on idle. |
The framed_un_ov parameter specifies the actions undertaken by the DCE when a transmit data buffer underrun or overrun condition occurs immediately after a non-flag octet. This is while operating in Framed sub-Mode. The framed_un_ov parameters are:
framed_un_ov | |
---|---|
0 | In Framed sub-Mode, DCE transmits abort on underrun in middle of frame. Default. |
1 | In Framed sub-Mode, DCE transmits a flag on underrun in middle of frame, and notifies DTE of underrun or overrun. |
The hd_auto parameter specifies whether or not, in V.34 half-duplex operation, additional procedures besides those specified in section 12/V.34 shall be performed by the DCE when switching from primary channel to secondary channel operation and vice versa. The hd_auto parameters are:
hd_auto | |
---|---|
0 | When switching between primary and secondary channel operation in V.34 half duplex, the DCE only executes those procedures defined in section 12/V.34. Default. |
1 | When switching between primary and secondary channel operation in V.34 half duplex, the DCE executes additional procedures as described in section 8.8.5 besides those defined in section 12/V.34. |
The crc_type parameter specifies the CRC polynomial used while operating in Framed sub-Mode. The crc_type parameters are:
crc_type | |
---|---|
0 | CRC generation and checking disabled. Default. |
1 | In Framed sub-Mode, the 16 bit CRC specified in section 8.1.1.6/V.42 is generated by the DCE in the transmit direction, and checked by the DCE in the receive direction. |
2 | In Framed sub-Mode, the 32 bit CRC specified in section 8.1.1.6/V.42 is generated by the DCE in the transmit direction, and checked by the DCE in the receive direction. |
The nrzi_en parameter specifies if Non Return to Zero Inverted (NRZI) encoding is to be used by the DCE for transmit and receive data. The nrzi_en parameters are:
nrzi_en | |
---|---|
0 | NRZI encoding and decoding disabled. Default. |
1 | NRZI encoding enabled in the DCE in the transmit direction, and NRZI decoding enabled in the DCE in the receive direction. |
The syn1 parameter specifies the octet value(s) to be used while performing character-oriented framing. When trans_idle=0, syn1 specifies the 8 bit transmit idle sequence to be used by the DCE. When trans_idle=1, syn1 specifies the 8 bit synchronization sequence to be used by the DCE. When trans_idle=2, syn1 specifies the first 8 bits of 16 bit synchronization sequence to be used by the DCE. The default setting for syn1 is 255.
The syn2 parameter specifies the octet value(s) to be used while performing character-oriented framing. When trans_idle=2, syn2 specifies the last 8 bits of 16 bit synchronization sequence to be used by the DCE. The default setting for syn2 is 255.
+ESR Selective Repeat This command controls the use of the selective repeat (SREJ) option in V.42 (if present in the DCE).
The format for AT+ESR is: AT+ESR=<value> The Value parameters are:
Value | |
---|---|
0 | Do not use SREJ |
1 | Use SREJ if available in remote DCE; continue without it if not. Default. |
2 | Use SREJ if available in remote DCE; iscontinue if SREJ is not available. |
+FCCLASS Service Class Identification
+GCAP Request Complete Capabilities List This command causes your modem to display one or more lines of information reporting the +n commands available in your modem.
+ITF Transmit Flow Control Thresholds This command allows the DTE to determine the input buffer size in the DCE for data on curcuit 103 from the DTE, to control the thresholds used for folw control of such data, and to control how often the DCE reports to the DTE the number of octets in this buffer. This parameter is ignored in Direct and Synchronous Modes, shere flow control is not used. The Off and On parameters are applicable in Synchronous Access, Frame Tunneling, Buffered V.14, and error control modes. The Report Period parameter is applicable only in Synchronous Access mode. The format for AT+ITF is: AT+ITF=<off>,<on>,<report_period>
+MS Select Modulation This command allows you to select a specific modulation, enable or disable automode, and specify the highest and lowest connection rates for your modem.
The command format for AT+MS is: AT+MS = <mod>,<automode>,<minimum rate>,<maximum rate> <x_law>, <rb_signal>, <Maxup_rate>
Mod | For K56flex, this field is 56. |
Automode | For automode, this field is 1. |
Min_rate | This value cnnot be used as in V.34 mode. If it is set to some value and the line cannot support that value, then the modem will not disconnect as in V.34. |
Max_rate | The max value for this field is 56000. |
X_law | For A-law use 1, for u-law use 0. |
Rb_signal | To enable RBS detection use 1. |
Maxup_rate | The max value for this field is 33600. |
You can leave a parameter at its current value by leaving that parameter's place blank and entering a comma to separate the parameters or by entering a carriage return ([CR]) if it is the last parameter. To specify a preferred modulation, enter a character designation from the <mod> column of the following table. The Mod parameter defined:
<mod> | Modulation | Possible Rates (bps)1 | Notes |
---|---|---|---|
0 | V.21 | 300 | |
1 | V.22 | 1200 | |
2 | V.22bis | 2400 or 1200 | |
3 | V.23 | 12002 | |
9 | V.32 | 9600 or 4800 | |
10 | V.32bis | 14400, 12000, 9600, 7200, or 4800 | |
11 | V.34 | 33600, 31200, 28800, 26400, 24000, 19200, 16800, 14400, 12000, 9600, 7200, 4800, or 2400 | |
64 | Bell 103 | 300 | |
69 | Bell 212 | 1200 | |
56 | K56flex | 56000, 54000, 52000, 50000, 48000, 46000, 44000, 42000, 40000, 38000, 36000, 34000, 32000 | Default |
1See optional
<automode>, <minimum rate>, and <maximum
rate> parameters. 2For V.23, originating modes transmit at 75 bps and receive at 1200 bps; answering modes transmit at 1200 bps and receive at 75 bps. The rate is always specified as 1200 bps. |
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