MULTI-TECH SYSTEMS, INC.
MT5634ZPW, MT3356ZPW, MT3334ZPW
Card Type | Modem |
Chip Set | Unidentified |
I/O Options | Line in, line out, microphone in, speaker out |
Maximum Modem Rate | 56Kbps |
Maximum Fax Rate | 14.4Kbps |
Data Modulation Protocol | Bell 103/212A ITU-T V.22, V.22bis, V.32ter, V.32bis, V.34, 56Kflex |
Fax Modulation Protocol | ITU-T V.17, V.27ter, V.29 |
Error Correction/Compression | MNP5, V.42, V.42bis |
Fax Class | Class I |
Data Bus | 16-bit ISA |

CONNECTIONS | ||||||
Function | Label | Function | Label | |||
Line out (RJ-11) | CN1 | Speaker out | CN3 | |||
Line in (RJ-11) | CN2 | Microphone in | CN4 | |||
SUPPORTED COMMAND SET |
Basic AT Commands |
AT, ‘+++’, A/ |
A, C, E, F, H, M, Q, V |
&C, &F, &G, &V, &Z |
Extended AT Commands |
\V |
Special Commands |
-C |
S Registers |
S0, S1, S2, S3, S4, S5, S10, S30 |
Note: See MHI Help File for full command documentation. |
Proprietary AT Command Set
AUTO-MODE DETECTION | |
Type: | Configuration |
Format: | AT [cmds] Nn [cmds] |
Description: | Selects various options for the automatic detection and negotiation of protocols during the handshake process if the modem is communicating with a remote modem of dissimilar speed. |
Command | Function |
N0 | In originate mode, handshake begins at line speed designated by the S37 register and the B command |
í N1 | In originate mode, handshake begins at line speed designated by the S37 register. and the B command Modem can shift to a slower speed if necessary. |
AUXILLARY RELAY CONTROL | |
Type: | Configuration |
Format: | AT [cmds] &J [cmds] |
Description: | Controls auxiliary relay |
Command | Function |
&J0 | Auxiliary relay remains open |
COMMUNICATION PROTOCOLS | |
Type: | Configuration |
Format: | AT [cmds] Bn [cmds] |
Description: | Selects the communication protocol for data calls |
Command | Protocol |
B0 | Modem will use ITU-T V.22 at 1200bps. |
B1 | Modem will use Bell 212A at 1200bps. |
B2 | ITU-T V.23 reverse channel disabled |
B3 | ITU-T V.23 reverse channel disabled |
B15 | Modem will use ITU-T V.21 at 300bps. |
B16 | Modem will use Bell 103J at 300bps. |
COMMUNICATIONS MODE | |
Type: | Configuration |
Format: | AT [cmds] &Mn [cmds] |
Description: | Selects communications mode |
Command | Mode |
&M0 | Asynchronous mode |
COMMUNICATIONS MODE | |
Type: | Configuration |
Format: | AT [cmds] &Qn [cmds] |
Description: | Selects communications mode options |
Command | Mode |
&Q0 | Asynchronous mode, serial port speed follows connect speed. |
í &Q5 | Error correction mode |
&Q6 | Buffered asynchronous mode |
DATA SET READY (DSR) | |
Type: | Configuration |
Format: | AT [cmds] &Sn [cmds] |
Description: | Selects DSR options |
Command | Function |
&S0 | DSR forced high |
&S1 | DSR high only while modem is connected |
DATA TERMINAL READY (DTR) | |
Type: | Configuration |
Format: | AT [cmds] &Dn [cmds] |
Description: | Selects modem response to DTR |
Command | Function |
&D0 | Modem does not respond to DTR |
&D1 | Modem goes to command mode after DTR goes is off |
í &D2 | Modem goes to command mode and disconnects (hangs up) after DTR goes off; Auto-Answer is disabled. |
&D3 | Modem is initialized after DTR goes off |
DIAL | |
Type: | Immediate |
Format: | AT [cmds] D<#> [cmds] |
Description: | Dials telephone number according to any modifiers included in the string |
Note: | Any combination of modifiers can be used to produce the desired dial functions in sequence. |
Command | Function |
DL | Re-dial last number |
DP | Pulse dialing enabled |
DSn | Dial stored telephone number n |
DT | Tone dialing enabled/Pulse dialing disabled |
DW | Dialing resumed following dial tone detection |
D, | Dialing paused for amount of time specified in S8 register |
D! | Flash function initiated. Modem commanded to go off-hook for specified time before returning on-hook. |
D@ | Wait for quiet Answer function enabled. Modem waits until a "quiet answer," a ring-back signal followed by silence up to the time specified in S7, is received prior to executing the rest of the dial string. |
D; | Modem returned to idle state after dialing. The semicolon can only be placed at the end of the dial command. |
D$ | Calling card "Bong" detection enabled |
DV | Switch to speakerphone |
D^ | Data calling tone transmission disabled |
FLOW CONTROL | |
Type: | Configuration |
Format: | AT [cmds] &Kn [cmds] |
Description: | Enables flow control options |
Command | Function |
&K0 | Flow control disabled |
í &K3 | RTS to CTS flow control enabled |
&K4 | XON/XOFF flow control enabled |
LONG SPACE DISCONNECT | |
Type: | Configuration |
Format: | AT [cmds] Yn [cmds] |
Description: | Commands the modem to disconnect after a 1.6 second break is detected |
Command | Function |
Y0 | Long space disconnect function disabled |
ON-LINE | |
Type: | Immediate |
Format: | AT [cmds] On |
Description: | Instructs the modem to return to on-line state. |
Command | Function |
O0 | Return to on-line state. |
O1 | Return to on-line state and initiate retrain sequence. |
O3 | Return to on-line state and initiate renegotiation sequence. |
REPORT INFORMATION | |
Type: | Immediate |
Format: | AT [cmds] In [cmds] |
Description: | Displays information requested |
Command | Function |
I0 | Reports default speed and controller firmware code |
I1 | Reports ROM checksum |
I2 | Tests and reports ROM checksum |
I3 | Reports default speed and controller firmware code |
I4 | Reports data pump model and revision code |
I9 | Reports country code |
I11 | Reports diagnostic information for the last modem connection |
RESTORE PROFILE ON POWER-UP | |
Type: | Configuration |
Format: | AT [cmds] &Yn [cmds] |
Description: | Restores a selected profile into the active profile on power-up (hard reset) |
Command | Function |
&Y0 | Restore profile 0 on power-up |
SELECT CALL PROGRESS RESULT CODES | |
Type: | Configuration |
Format: | AT [cmds] Xn [cmds] |
Description: | Enables selection of tone detection and associated result code format options |
Command | Function |
X0 | Busy and dial tone detection disabled; basic result codes enabled. |
X1 | Busy and dial tone detection disabled; extended result codes enabled. |
X2 | Busy tone detection disabled, dial tone detection enabled; extended result codes enabled. |
X3 | Busy tone detection enabled, dial tone detection disabled; extended result codes enabled. |
í X4 | Busy and dial tone detection disabled; extended result codes enabled. |
X5 | Busy and dial tone detection disabled; extended result codes enabled. |
X6 | Busy and dial tone detection disabled; extended result codes enabled. |
X7 | Busy and dial tone detection disabled; basic result codes enabled. |
SOFT RESET | |
Type: | Immediate |
Format: | AT [cmds] Zn [cmds] |
Description: | Restores modem profiles previously saved in non-volatile RAM using the &W command. |
Command | Function |
Z0 | Restore modem to profile saved by last &W command |
Z1 | Restore modem to profile saved by last &W command |
SPEAKER VOLUME | |
Type: | Configuration |
Format: | AT [cmds] Ln [cmds] |
Description: | Controls speaker volume |
Command | Function |
L0 | Low volume setting |
L1 | Low volume setting |
í L2 | Medium volume setting |
L3 | Highest volume setting |
STORE ACTIVE PROFILE | |
Type: | Configuration |
Format: | AT [cmds] &Wn [cmds] |
Description: | Writes the values for the active profile into the non-volatile RAM |
Command | Function |
&W0 | Write the active profile to NVRAM |
TEST MODES | |
Type: | Immediate |
Format: | AT [cmds] &Tn |
Description: | Selects test options |
Command | Function |
&T0 | End current test |
&T1 | Begin local analog loopback test |
&T3 | Begin local digital loopback |
&T6 | Request remote digital loopback |
V.32 - AUTO-RETRAIN | |
Type: | Configuration |
Format: | AT [cmds] &Bn [cmds] |
Description: | Controls auto-retrain function if poor line quality is detected |
Command | Function |
&B1 | Auto-retrain enabled if line quality is poor |
Extended AT Commands
BREAK TYPE | |
Type: | Configuration |
Format: | AT [cmds] \Kn [cmds] |
Description: | Configures action of break signal |
Command | Function |
\K5 | Sends break received from DTE to the remote modem |
COMPRESSION | |
Type: | Configuration |
Format: | AT [cmds] %Cn [cmds] |
Description: | Selects data compression |
Command | Function |
%C0 | Data compression disabled |
%C1 | V.42bis/MNP5 enabled |
CONNECT MODE | |
Type: | Configuration |
Format: | AT [cmds] \Nn [cmds] |
Description: | Controls the type of connection the modem will operate in |
Command | Function |
\N0 | Normal mode enabled |
\N1 | Direct mode enabled |
\N2 | MNP reliable mode enabled |
í \N3 | V.42/MNP auto-reliable mode enabled |
\N4 | V.42 reliable mode enabled |
\N5 | V.42/MNP auto-reliable mode enabled |
\N7 | V.42/MNP auto-reliable mode enabled |
DISPLAY BLACKLIST NUMBERS | |
Type: | Immediate |
Format: | AT [cmds] %B [cmds] |
Description: | Displays the list of all the numbers on the blacklist. Returns ERROR if blacklisting is disabled. |
FLOW CONTROL | |
Type: | Configuration |
Format: | AT [cmds] \Gn [cmds] |
Description: | Command nonfunctional; for compatibility purposes only |
Command | Function |
\G0 | Returns OK for backward compatibility |
FLOW CONTROL TYPE | |
Type: | Configuration |
Format: | AT [cmds] \Qn [cmds] |
Description: | Sets type of flow control used by modem |
Command | Function |
\Q0 | Flow control disabled |
\Q1 | Bi-directional XON/XOFF flow control enabled |
í \Q3 | Bi-directional RTS/CTS flow control enabled |
INACTIVITY TIMER | |
Type: | Configuration |
Format: | AT [cmds] \Tn [cmds] |
Description: | Disables the inactivity timer |
Command | Function |
\T0 | Inactivity timer disabled |
LOCK SERIAL PORT | |
Type: | Configuration |
Format: | AT [cmds] \Jn [cmds] |
Description: | Sets operation of serial port speed |
Command | Function |
\J0 | Serial speed locked |
XON/XOFF PASS-THROUGH | |
Type: | Configuration |
Format: | AT [cmds] \Xn [cmds] |
Description: | Selects whether XON/XOFF signals are sent to remote modem |
Command | Function |
\X0 | XON/XOFF signals trapped by local modem |
Special Commands
ASYNCHRONOUS WORD LENGTH | |
Type: | Configuration |
Format: | AT [cmds] +ES=n [cmds] |
Description: | Allows an H.324 video application direct access to the synchronous data channel. +ES=? Shows allowable value (6) +ES? Queries setting |
Command | Function |
+ES=6 | Allows an H.324 video application direct access to the synchronous data channel |
SPEAKER CODEC LOOPBACK | |
Type: | Configuration |
Format: | AT [cmds] &&S [cmds] |
Description: | Provides a loopback from the microphone to the speaker. |
Note: | For testing and debugginh purposes only |
TEST DSP56K CODE VERSION & CHECKSUM - EXTERNAL RAM | |
Type: | Immediate |
Format: | AT [cmds] %T125 <cr> |
Description: | Tests DSP56K code version & checksum running in external RAM. |
TEST DSP56K CODE VERSION & CHECKSUM - INTERNAL ROM | |
Type: | Immediate |
Format: | AT [cmds] %T124 <cr> |
Description: | Tests DSP56K code version & checksum running in internal ROM. |
TEST EXTERNAL RAM | |
Type: | Immediate |
Format: | AT [cmds] %T94 <cr> |
Description: | Tests external RAM. Returns PASS or FAIL |
S(STATUS) -REGISTERS
56K DCE LINE SPEED | |
Type: | Register |
Format | AT [cmds] S38=n [cmds] |
Description: | Sets the maximum allowable 56K downstream rate attempted during handshake process. |
Command | Function |
S38=0 | 56K disabled |
S38=1 | 56K automatic speed select |
S38=2 | 32.0Kbps |
S38=3 | 34.0Kbps |
S38=4 | 36.0Kbps |
S38=5 | 38.0Kbps |
S38=6 | 40.0Kbps |
S38=7 | 42.0Kbps |
S38=8 | 44.0Kbps |
S38=9 | 46.0Kbps |
S38=10 | 48.0Kbps |
S38=11 | 50.0Kbps |
S38=12 | 52.0Kbps |
S38=13 | 54.0Kbps |
S38=14 | 56.0Kbps |
56K DIGITAL LOSS | |||
Type: | Register | ||
Format: | AT [cmds] S108=n [cmds] | ||
Description: | Selects the 56Kbps digital loss if using the modem thru a PBX line | ||
Command | Function | ||
S108=0 | -0dB digital loss; robbed bit signaling disabled | ||
S108=1 | -3dB PBX digital loss | ||
S108=2 | -2dB digital loss | ||
S108=3 | -3dB digital loss | ||
í S108=6 | -6dB digital loss | ||
S108=7 | -0dB digital loss; robbed bit signaling enabled | ||
DCE LINE SPEED | |
Type: | Register |
Format | AT [cmds] S37=n [cmds] |
Description: | Sets the maximum allowable data exchange rate attempted during handshake process. |
Command | Function |
S37=0 | Maximum speed |
S37=1 | Reserved |
S37=2 | 1200/75bps |
S37=3 | 300bps |
S37=4 | Reserved |
S37=5 | 1200bps |
S37=6 | 2400bps |
S37=7 | 4800bps |
S37=8 | 7200bps |
S37=9 | 9600bps |
S37=10 | 12.0Kbps |
S37=11 | 14.4Kbps |
S37=12 | 16.8Kbps |
S37=13 | 19.2Kbps |
S37=14 | 21.6Kbps |
S37=15 | 24.0Kbps |
S37=16 | 26.4Kbps |
S37=17 | 28.8Kbps |
S37=18 | 31.2Kbps |
S37=19 | 33.6Kbps |
DIALING DELAY | |
Type: | Register |
Format | AT [cmds] S6=n [cmds] |
Range: | 2-65 |
Unit: | 1 second |
Description: | Duration of delay after modem goes off-hook and before dialing |
ERROR CORRECTION NEGOTIATION | |||
Type: | Register | ||
Format | AT [cmds] S36=n [cmds] | ||
Description: | Selects the action of the modem if it fails to connect when error control is selected. | ||
Command | S48=7 | S48=128 | |
S36=0 | LAPM or hang-up | Not used | |
S36=1 | LAPM or Asynchronous | Asynchronous | |
S36=2 | LAPM or hang-up | Not used | |
S36=3 | LAPM or Asynchronous | Asynchronous | |
S36=4 | LAPM, MNP, or hang-up | MNP or hang-up | |
S36=5 | LAPM, MNP, or Asynchronous | MNP or Asynchronous | |
S36=6 | LAPM, MNP, or hang-up | MNP or hang-up | |
S36=7 | LAPM, MNP, or Asynchronous | MNP or Asynchronous | |
FEATURE NEGOTIATION | ||
Type: | Register | |
Format: | AT [cmds] S48=n [cmds] | |
Range: | 7, 128 | |
Description: | Selects active error correction and compression protocols. See S36, error correction negotiation table | |
INACTIVITY TIMER | |
Type: | Register |
Format: | AT [cmds] S89=n [cmds] |
Range: | 0, 5-255 |
Default: | 10 |
Unit: | 1 second |
Description: | Sets the length of time that the modem does not receive information before it disconnects; S89=0 will disable. |
NO CARRIER TIME-OUT | |
Type: | Register |
Format | AT [cmds] S7=n [cmds] |
Range: | 1-255 |
Unit: | 1 second |
Description: | Maximum wait time the modem uses after dialing to detect a carrier signal from the remote modem for both originating and answering calls. |
PAUSE DURATION | |
Type: | Register |
Format | AT [cmds] S8=n [cmds] |
Range: | 0-65 |
Unit: | 1 second |
Description: | Duration of pause per comma (,) command used in a command or dial string |
TONE PULSE DURATION | |
Type: | Register |
Format | AT [cmds] S11=n [cmds] |
Range: | 50-150 |
Unit: | 1 ms |
Description: | DTMF tone pulse duration and time between tone pulses for tone dialing operations. |
V.25 CALLING TONE | |
Type: | Register |
Format | AT [cmds] S35=n [cmds] |
Range: | 0-1 |
Unit: | Decimal |
Description: | Enables V.25 data calling tone, which allows remote data/fax/voice discrimination |
Note: S35=0 disables V.25 data calling tone. | |
V.34 MODULATION | |
Type: | Register |
Format | AT [cmds] S28=n [cmds] |
Range: | 0-255 |
Unit: | Decimal |
Description: | Enables V.34 modulation |
Note: S28=0 disables V.34 modulation. | |
V32bis STARTUP MODE | |
Type: | Register |
Format | AT [cmds] S43=n [cmds] |
Range: | 0-1 |
Unit: | Decimal |
Description: | Enables V.32bis start-up auto mode operation |
Note: S43=0 disables V.32bis start-up auto mode. For testing purposes only. | |
V32bis, V.22bis AUTO RATE | |
Type: | Register |
Format | AT [cmds] S42=n [cmds] |
Range: | 0-1 |
Unit: | Decimal |
Description: | Enables V.32bis and V.22bis auto rate |
Note: S42=0 disables V.32bis and V.22bis auto rate. For testing purposes only. | |