MULTI-TECH SYSTEMS, INC.
MT224AH
Modem Type |
Data (synchronous/asynchronous) |
Maximum Data Rate |
2400bps |
Data Bus |
External |
Data Modulation Protocol |
Bell 103A/212A ITU-T V.21, V.22, V.22bis, V.23 |
Error Correction/Compression |
MNP5, V.42, V.42bis |
CONNECTIONS | |||
Purpose |
Location |
Purpose |
Location |
DC power |
CN1 |
Line in |
CN4 |
RS-232/422 |
CN2 |
Power switch |
SW1 |
Line out |
CN3 |
Volume |
R1 |
ASYNCHRONOUS/SYNCHRONOUS | |
Settings |
SW5/D |
Synchronous |
On |
» Asynchronous |
Off |
AUTO-ANSWER | |
Settings |
SW4/E |
» Enable auto answer/originate |
On |
Disable/answer |
Off |
Note: When SW5/B is set for Lease Line operation, the options on this switch change to Originate and Answer |
BLIND/WAIT DIALING | |
Settings |
SW5/C |
Wait for dial tone |
On |
» Blind dialing |
Off |
BAUD RATE | |
Settings |
SW2 |
1200bps |
Position 1 |
300bps |
Position 2 |
2400bps |
Position 3 |
CD/DSR | |
Settings |
SW4/F |
» CD/DSR normal |
On |
CD/DSR forced high |
Off |
COMMAND CHARACTERS | |
Settings |
SW4/D |
» Echo enable |
On |
Echo disable |
Off |
COMMAND MODE | |
Settings |
SW4/H |
Disable |
On |
» Enable |
Off |
CTS | |
Settings |
SW5/A |
» CTS forced high |
On |
CTS normal |
Off |
CTS/RTS | |
Settings |
JP2 |
» CTS follows RTS |
Pins 1 & 2 closed |
CTS forced high until disconnect |
Pins 2 & 3 closed |
DSR | |
Settings |
JP3 |
» DSR follows CD |
Pins 2 & 3 closed |
DSR follows OH |
Pins 1 & 2 closed |
FORCED DTR | |
Settings |
SW4/A |
DTR normal |
On |
» DTR forced high |
Off |
JACK TYPE | |
Settings |
SW4/G |
» RJ11 |
On |
RJ12/13 |
Off |
RESULT CODES | |
Settings |
SW4/B |
» Verbose |
On |
Terse |
Off |
RESULT CODES | |
Settings |
SW4/C |
Disable |
On |
» Enable |
Off |
RTS | |
Settings |
JP1 |
» RTS forced high |
Pins 1 & 2 closed |
RTS normal |
Pins 2 & 3 closed |
SWITCHED/LEASE LINE | |
Settings |
SW5/B |
» Switched |
On |
Lease line |
Off |
VOICE/DATA MODE | |
Settings |
SW3 |
Answer |
Position 1 |
Originate |
Position 2 |
DIAGNOSTIC LED(S) | |||
LED |
Color |
Status |
Condition |
SD |
Red |
On |
Modem is transmitting data |
SD |
Red |
Off |
Modem is not transmitting data |
RD |
Red |
On |
Modem is receiving data |
RD |
Red |
Off |
Modem is not receiving data |
CD |
Red |
On |
Carrier signal detected |
CD |
Red |
Off |
Carrier signal not detected |
24 |
Red |
Blinking fast |
Modem connected at 2400bps in reliable mode |
24 |
Red |
Blinking slow |
Modem connected at 2400bps with data compression |
24 |
Red |
Off |
Modem not connected at 2400bps |
12 |
Red |
Blinking fast |
Modem connected at 1200bps in reliable mode |
12 |
Red |
Blinking slow |
Modem connected at 1200bps with data compression |
12 |
Red |
Off |
Modem not connected at 1200bps |
OH |
Red |
On |
Modem is off-hook |
OH |
Red |
Off |
Modem is on-hook |
TR |
Red |
On |
DTR signal is high |
TR |
Red |
Off |
DTR signal is low |
Proprietary AT Command Set
BLIND DIALING | |
Type: |
Configuration |
Format: |
AT [cmds] Bn [cmds] |
Example: |
AT B0 <CR> |
Description: |
Selects blind dial or wait-for-dial-tone. |
Command |
Function |
» B0 |
Modem will blind dial. |
B1 |
Modem will wait for dial tone before dialing. |
CD SIGNAL | |
Type: |
Configuration |
Format: |
AT [cmds] &Cn [cmds] |
Example: |
AT &C3 $D0 <CR> |
Description: |
Configures the behavior of the carrier detect signal. |
Command |
Function |
&C0 |
CD forced high. |
» &C1 |
CD normal. |
&C2 |
CD forced high except during disconnect. |
COMMAND SET | |
Type: |
Configuration |
Format: |
AT [cmds] &Qn [cmds] |
Example: |
AT &Q0 <CR> |
Description: |
Selects standard Hayes or custom command sets. |
Command |
Function |
» &Q0 |
Multi-Tech custom command set enabled. |
&Q1 |
Standard Hayes command set enabled. |
DIAL STORED PHONE NUMBER | |
Type: |
Immediate |
Format: |
AT [cmds] Nn1 [Nn2, Nn3...] |
Example: |
ATM0 N1N3N5 <CR> |
Description: |
Dials stored phone number(s). If the first number is busy, the modem will proceed to the next number in the list. |
DSR/CTS/CD TIMEOUT | |
Type: |
Register |
Format: |
AT [cmds] S24=n [cmds] |
Example: |
ATS24=40 <CR> |
Default: |
20 |
Range: |
0-255 |
Unit: |
50 ms |
Description: |
Sets the time to drop the DSR, CTS, and CD signals to hangup. |
DTR DIALING | |
Type: |
Configuration |
Format: |
AT [cmds] $Dn [cmds] |
Example: |
AT $D1 DT555-1212 <CR> |
Description: |
Selects the DTR dialing function. |
Command |
Function |
» $D0 |
DTR dialing disabled. |
$D1 |
DTR dialing enabled. |
DTR TIMEOUT | |
Type: |
Register |
Format: |
AT [cmds] S25=n [cmds] |
Example: |
ATS25=30 <CR> |
Default: |
0 |
Range: |
0-255 |
Unit: |
.1 second |
Description: |
Sets the time to drop the DTR signal to hangup. |
Note: |
Setting S25 to 0 sets the DTR timeout to 50 ms. |
DUPLEX | |
Type: |
Configuration |
Format: |
AT [cmds] Fn [cmds] |
Example: |
AT F1 &W <CR> |
Description: |
Controls duplex mode. |
Command |
Function |
F0 |
Half duplex enabled. |
» F1 |
Full duplex enabled. |
HELP SCREENS | |
Type: |
Immediate |
Format: |
AT $Hn |
Example: |
AT $H1 <CR> |
Description: |
Shows modem help screens. |
Command |
Function |
$H1 |
Shows help screen 1. |
$H2 |
Shows help screen 2. |
$H3 |
Shows help screen 3. |
$H4 |
Shows help screen 4. |
LIST CONFIGURATION | |
Type: |
Immediate |
Format: |
AT Ln |
Example: |
AT L5 <CR> |
Description: |
Lists modem configuration. |
Command |
Function |
L0 |
Lists all phone numbers in memory. |
L5 |
Lists all settings. |
L6 |
Lists the values of all S-registers. |
LOOPBACK TEST MODE | |
Type: |
Configuration |
Format: |
AT [cmds] Un [cmds] |
Example: |
AT U2 &W <CR> |
Description: |
Places modem in test mode. |
Command |
Function |
U0 |
Begin local analog loopback test in originate mode. |
U1 |
Begin local analog loopback test in answer mode. |
U2 |
Request remote digital loopback |
U3 |
Begin local digital loopback. |
PROTOCOL | |
Type: |
Configuration |
Format: |
AT [cmds] &Vn [cmds] |
Example: |
AT &V1 <CR> |
Description: |
Selects the protocol for low-speed data calls. |
Command |
Function |
&V0 |
Bell protocols. |
» &V1 |
ITU-T protocols. |
REDIAL | |
Type: |
Immediate |
Format: |
A: |
Example: |
A: |
Description: |
Redials the last number dialed until it is no longer busy. |
Note: |
Do not precede this command with AT or follow it with <CR>. |
STORE PHONE NUMBER IN NVRAM | |
Type: |
Configuration |
Format: |
AT [cmds] D<#>N<0-9> |
Example: |
ATD1(303)-443-3323N6 <CR> |
Description: |
Stores a phone number in the modem’s memory. Only the dialstring before the N will be stored. |
WAIT FOR DIAL TONE | |
Type: |
Immediate |
Format: |
AT [cmds] W [cmds] |
Example: |
AT W <CR> |
Description: |
Wait for new dial tone. |