Data-Linc Group DLM4500 User manual

USER GUIDE
I
NDUSTRIAL
D
ATA
C
OMMUNICATIONS
It is essential that all instructions contained in the User Guide are followed precisely to ensure proper operation of equipment.
Dial-Up/LeasedLineModem
DLM4500

DATA-LINC GROUP
PN 161-10008-001A
Rev 4/04
DLM4500 User Guide
Patents
This device covered by one or more of the following patents: 6,031,867; 6,012,113; 6,009,082; 5,905,794;
5,864,560; 5,815,567; 5,815,503; 5,812,534; 5,809,068; 5,790,532; 5,764,628; 5,764,627; 5,754,589;
D394,250; 5,724,356; 5,673,268; 5,673,257; 5,644,594; 5,628,030; 5,619,508; 5,617,423; 5,600,649;
5,592,586; 5,577,041; 5,574,725; D374,222; 5,559,793; 5,546,448; 5,546,395; 5,535,204; 5,500,859;
5,471,470; 5,463,616; 5,453,986; 5,452,289; 5,450,425; D361,764; D355,658; D355,653; D353,598;
D353,144; 5,355,365; 5,309,562; 5,301,274 Other Patents Pending.

DATA-LINC GROUP
1
DLM4500 User Guide
PN 161-10008-001A
rev 4/04
Table of Contents Page
Introduction 3
Connection Points and LED Descriptions 4
Equipment Connections and Interface Descriptions 5
Quick Start 7
Quick Configuration 10
Technical Specifications 12
Technical Support 14
ReturnMaterialAuthorization 14
Contact Information 14
AppendixA
Enclosure Dimensions 15
AppendixB
Complete AT Commands 16
Complete S-Registers 27
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Introduction
TheData-LincGroupDLM4500 modemis designedto workon publicdial-up telephonesystems. Themodem willwork on
both dial-up voice grade phone lines and leased lines. It connects to a normal telephone service using a RJ-11 jack (2 wire)
and connects to the users equipment via a 9-pin DB-9 connector utilizing RS232 signals and screw terminals if aAE-485
(2-wire)orAE-422(4-wire) unit.
TheData-Linc Group DLM4500 is a compact modem designed and manufactured tooperate in industrial applications. It
hasa wideDC voltageinput power range and the operating temperature range of this device is -40° to +70° C.
The mechanical and electrical specifications are listed inAppendix B.
TheDLM4500 hasfront panelLEDindicators forPower (Red),DataIn from user equipment (Yellow), DataOut to users
equipment(Green),and Carrier Detect(Amber).
The DLM4500 is configured using ‘AT’ style commands sent via the 9-pin port while the modem is in ‘Command Mode’.
Factory default is set at 9600 baud.All normal configurations are performed using the RS232 connection on the front panel
even if the units are aAE-485 orAE-422 model.
Acomplete list of ‘AT’ commands are in appendixA. Note that allAT command character strings must end with a carriage
return character (Enter key, ctrl M, 0xd hex).
Systems Examples
Diagram 1
Dial-Up
Diagram 2
Leased Line
LINE DATA
IC PO
DLM4500
DATA-LINC GROUP
[phone]
RESET
POWER
VDC
- +
LINE DATA
IC PO
DLM4500
DATA-LINC GROUP
[phone]
RESET
POWER
VDC
- +
+
LINE DATA
IC PO
DLM4500
DATA-LINC GROUP
[phone]
RESET
POWER
VDC
- +
+
LINE DATA
IC PO
DLM4500
DATA-LINC GROUP
[phone]
RESET
POWER
VDC
- +
+
RS-232
RS-232
RS-232
Remote 0
Remote 1Remote 2
Master
Dial-Up Connection
to Telco Network
Dial-Up Connection
to Telco Network
Dial-Up Connection
to Telco Network
Dial-Up Connection
to Telco Network
RS-232
LINE DATA
IC PO
DLM4500
DATA-LINC GROUP
[phone]
RESET
POWER
VDC
- +
LINE DATA
IC PO
DLM4500
DATA-LINC GROUP
[phone]
RESET
POWER
VDC
- +
+
RS-232
Remote
Master
Telco or Private
Leased Line
RS-232
Telco or Private
Leased Line

DATA-LINC GROUP
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DLM4500 User Guide
Connection Points and LED Descriptions
Figure 1
Front Panel Connections – (Left to Right)
RJ-11—Phone Line
DB-9— DataPort RS232
pin 1 CD Out (Carrier Detect)
pin 2 Data Out
pin 3 Data In
pin 4 DTR In (Data terminal ready)
pin 5 Signal Ground
pin 6 DSR Out (Data set ready)
pin 7 RTS In (Request to send)
pin 8 CTS (Clear to send)
pin 9 N/C
Push-Button Switch — Modem Reset
LedArray
O - Green(data out/line in)
I - Yellow (data in/line out)
C - Amber(line carrierdetect)
P - Red(DCpower)
2-Position Terminal Block — DC Power In (note the polarity + and –)
Figure 2
Rear Panel Connections – AE-485 and AE-422 (when option is installed)
AE-485 AE-422
1 N.C. 1 DO- (Data Out -)
2 I/O - (Data in/out-) 2 DO + (Data Out +)
3 I/O + (Data in/out +) 3 DI- (Data In-)
4 N.C. 4 DI+ (Data In+)
P
C
I
O
DATA-LINC GROUP
DLM4500
[phone]
LINE DATA
- +
VDC
RESET
POWER
+
-
(AE-485) - +
(AE-422) DO - DO + DI - DI +
12 34

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Equipment Connections
TheDLM4500 can be purchased with three types of serialinterfaces. RS232only (standard),AE-4224-wire (optional), or
AE-485 2-wire (optional).All units have the RS232 connector on the front. This is always used to configure the modem.The
AE-422 andAE-485 connections are on the rear of the unit. The units can have the RS232 connected at the same time as
theAE-485 orAE-422, but you can not send data into both the front and rear connections at the same time or data
collisions will occur.
RS232
The front RS232 connection is built as a DCE configuration.
For a RS232 connection, use a cable that matches the user equipment. If the users equipment is also a DCE device a null
modem cable must be used. If it is a DTE device then a straight through cable will work.
AE-422
TheAE-422 connections consist of a wire pair for data out, and a wire pair for data in. Both pairs have a plus (+) and a
minus (-) polarity. To make aAE-422 connection, wire the DLM4500 Data In pair to the Data out from connecting
equipment. Verify that the Data-In LED on the front panel is not on. If it is on all the time turn the wire pair over (reversed
polarity). Data Linc GroupAE-422 usually connects the ‘+’ to an A contact and connects the ‘–‘ wire to a B contact.
Now send some data characters out of the connected equipment. The Data-In LED should flash. If it does not, check that
the Data OUT from your equipment is connected to the Data-IN on the rear of the DLM4500.
If the DLM4500 In LED flashes then connect the DLM4500 Data-Out wire pair to the connecting equipment. Note the
polarity of the connection made to the Data-In lines above. Use the same polarity on the Data-Out connection. Verify the
plus and minus polarity.
If no LED’s blink, then some things can be wrong are: (Note:At high baud rates the blinking may be very fast and faint.)
a. The modem is not connected to the equipment. -Check the cables.
b. DC power is missing or wired backwards-Check the power supply.
c. The equipment you are using is set for the wrong communications port. Match the programs port settings to the
computers physical port number that the cable is plugged into.
d.The equipmentsprogram is not running.
e.TheAE-422 wire pairs are notcross-connectedTX-to-RX andRX-to-TX, or either wirepairin inverted(+and –
lines are swapped backwards). Note that there are 7 ways to miss connect the 2 pairs, and only one way to
connect them correctly.
f.The communicationsport isnot anRS-422 device,or ifusing anRS-422 converterthe converteris brokenor
needs power.

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AE-485
TheAE-485 connection is made with one wire pair. This pair has a plus (+) and a minus (-) polarity.After connecting the
wire pair, send some data out of the connected equipment. The Data-In LED on the front panel should flash. If it does not,
invert the wire pair and try again. Data-Linc GroupAE-485 usually connects the ‘+’to anAcontact and connects the ‘–‘ wire
to a B contact.
If no LED’s blink, then some things that could be wrong. (Note: at high baud rates the blinking may be very fast or faint.)
a. The modem is not connected to the equipment. -Check the cables.
b. DC power is missing or wired backwards -Check power supply.
c. The equipment you are using is set for the wrong communications port. Match the programs port settings to the
computers physical port number that the cable is plugged into.
d.The equipmentsprogram is not running.
e.TheAE-485 wire pairis inverted (+and – lines are swapped backwards).
f. The communications port is not an RS-485 device, or if using an RS-485 converter the converter is broken or
needs power.

DATA-LINC GROUP
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Dial Up Quick Start and Testing
The following setup procedure is for a DLM4500 in Dial-Up mode. It assumes that two phone jacks of dial-up lines are
available
1.Unpack the modem(s).
2. Verify that you have all of the parts and cables to power and connect the modem to your equipment.You must be using
a PC with an RS232 serial communication port.All three versions of the DLM4500 can be configured via the RS232 port.
3. Start a terminal program from the PC. Use a program like Hyperterminal or Procomm. Set the communications settings
in the terminal program.You must set or verify the setting for at least the following parameters:
SerialCommunications Port Mumber
Speed:Baud Rate
Character ormat: Parity, Number of Data bits, Number of Stop bits (n,8,1)
Handshake/ Flow Control:None
Figure 3 Figure 4 Figure 5
4.Apply DC power to the DLM4500. Check the Power LED. It must be ON. If not check:
a. DC power is off or disconnected. Check for the presence of a nominal 12 volts DC on the power connector.
b. DC power is wired backwards. Check the source voltage with a voltmeter.
5. Reset the modem by pressing the Reset button on the front of the unit. This resets the modem and returns theAT
command set to “last stored values” in NVRAM. The modem is ready to accept setup commands.
6. Connect the computer to the DLM4500 with a straight through 9 pin cable. DO NOTCONNECT THE PHONE LINEYET.
Check that only the RED Power LED is On.
7. Type the command string ‘AT’, then the Enter Key.The modem must reply with the characters ‘OK’. If this does not
happen, recheck step 6 above.
8.The DLM4500 will be configured to your application if the informationwas supplied to Data-Linc Group during the order
process. If not the Baud Rate and other paramater should be checked before connecting the modems (See Quick
Configuration for help)
9. Get the phone number of the modem you want to connect with. Connect a standard phone to the phone line. Pick up the
phone handset and verify that you get a dial tone. then remove the phone line from the phone and plug it into the
DLM4500.
10. Type the command string “ATDTxxx xxx xxxx” then the Enter Key. This is the standard dial string. (where the x’s(x) are
replaced with the 7 or 10 digit phone number)

DATA-LINC GROUP
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11. The modem will now take the phone line Off- hook and dial when the dial tone is received. The speaker will make
several noises including the dial tone. If a connection is made the modems speaker will go off, theAmber (carrier) LED
will illuminate and ‘Connect xxxx’ will display, where xxxx is the baud rate, and after that will display the error
correction modes if any is used.. If using a terminal program the modem will automatically be set in data transfer mode.
Failure to make a connection can be the result of:
a. Wrong phone number. Use a regular phone to dial the number and listen to the response.
b. No matching modem at the other end of the phone line.
c. Other modem must be set to answer the phone.
d. Other modem must be turned on.
e. Other modem must be plugged in.
f. This modem must be commanded to dial.
g. Connected software must support a modem and must dial out.
h. Modems at each end must have matching or compatible settings
12. Data can now be sent in either direction.or if a jumper is placed in the DB-9 Connector between pins 2 and 3 any
data sent from the master to the remote will be looped back. In this "Loopback" test the I and O LED’s should be
blinking when data is being sent back to the originating PC.
13. Disconnect the call. To set the modem into command mode while in data mode, send the escape sequence characters
[pause] +++ [pause] then wait for “OK”. Then type ATH(enter) to hang up an existing call. Unit will respond with “OK”.
End Dial-Up Quick Start and Testing
Leased Line Quick Start and Testing
The following setup procedure is for a DLM4500 in Leased Line mode. It assumes that two phone jacks of leased line or
phonecord wire is available for testing.
1.Unpack the modem(s).
2. Verify that you have all of the parts and cables to power and connect the modem to your equipment.You must be using
a PC with an RS232 serial communication port.All three versions of the DLM4500 can be configured via the RS232 port.
3. Start a terminal program from the PC. (Note: See Dial-Up Quick Start and Testing of setup help)
4.Apply DC power to the DLM4500. Check the Power LED. It must be ON. If not check:
a. DC power is off or disconnected. Check for the presence of a nominal 12 volts DC on the power connector.
b. DC power is wired backwards. Check the source voltage with a voltmeter.
5. Reset the modem by pressing the Reset button on the front of the unit. This resets the modem and returns theAT
command set to “last stored values” in NVRAM. The modem is ready to accept setup commands.
6. Connect the computer to the DLM4500 with a straight through 9 pin cable. DO NOTCONNECT THE PHONE LINEYET.
Check that only the RED Power LED is On.
7. Press reset button, wait one second ( in leased line mode the modems will only acceptAT commands for the first 10
seconds, and after 30 seconds should have started their connection process) then type the command string ‘AT’, then
the Enter Key. The modem must reply with the characters ‘OK’. If this does not happen, recheck step 6 above and try
again.

DATA-LINC GROUP
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8.The DLM4500 will be configured to your application if the informationwas supplied to Data-Linc Group during the order
process. if not the Modem Mode (ie Master or Remote), Baud Rate and other paramater should be checked before
connecting the modems (See Quick Configuration for help)
9.Connect a Master configured DLM4500 to aRemote configured DLM4500 using a phone RJ-11 cord. The modemswill
automatically connect after approximately 30 seconds. The carrier LED on both modems should light.
10. Leaving the PC computer connected to either of the modems, connect a wire jumper (bent paper clip) between pins 2
and 3 of the other (non-PC connected) DLM4500.
11. Type characters on the PC keyboard while running the terminal program. The characters must echo back on the display
exactly as typed.
12. Remove the 2-3 pins jumper, and the phone cord connection. Connect the DLM4500 to the leased line. Connect the
second modem to the RJ-11 at the other location. The modems will make a connection after approximately 30 seconds.
If the connection is dropped the units will automatically reset and try to restore the connection.
End Leased Line Quick Start and Testing

DATA-LINC GROUP
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Quick Configuration ***For Most Applications the DLM4500 Comes Preconfigured
Note:The Enter key produces theASCII character ‘cr’carriage return (decimal 13, hex 0d).
Note also that there are no ‘O’s (ohs) in any of the followingAT command string.All round
charactersare the number zero (0).
To verify the settings before and afterchanging parameterstype the command string:
AT&V (Enter) then examine the settings and registers displayed on the screen.
A. Set to Chipset’s default
AT&F0 (Enter)
Responds OK
B. Set Connection and Correction Modes
AT&D0&K0#P0%C0\K3\N4%E0$LB=3&W0(Enter)
Responds OK
C. Baud Rate
If this modem is to be forced to connect and communicate at a fixed baud rate, the following command will need to be
entered. If an auto-connect baud rate sequence is used between modems then skip this section and go to step D.
Note:The most industrial equipment are operatedat pre-selected fixed baud rates.TheseATcommands are
used to force the modem to connect at only the specified baud rate. It will not hunt to find a matching baud rate.
AT$SB9600$MB9600&W0 (Enter) - Where 9600 in both places is the desired baud rate
Responds OK
D. Mode
Dial-Up
Type:AT&L0%DC0&W0 (Enter)
Responds OK
Leased Line mode enter:
Master Type:AT&L1%DC1&W0 (Enter)
RespondsOK
Remote Type:AT&L2%DC1&W0 (Enter)
RespondsOK
Note: Leased line operations require one modem to be a Master and other to be a Remote.

DATA-LINC GROUP
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Short Description of AT Commands Used in Quick Configure Sections
Reconfiguring a DLM4500 after setting it to Leased Line mode
Since there is no jumper or switch to change between Leased Line and Dial-Up/Command Mode on the DLM4500, a
specialAT command is used during a 10 second time window after powering up or pressing the reset switch to allow
changingmodem settings.
To get a Leased Line configured DLM4500 modem intoCommand Modefollow these steps:
-Remove power from DLM4500
-Connect PC to RS232 9-pin port. Start aTerminal program
-Apply Power to DLM4500
-Press Reset on front panel
-Wait 1 or 2 seconds
-Type the following StringAT%DC0&L0<enter>
-Then follow the Quick Configuration Guide.
TheDLM4500 hasmany commands and various operating modes. It can be configured to perform underalmost alltype of
system designs. This manual does not try to cover each and every possible combination. If you are trying to use the
DLM4500 in a particular mode and you can not decide what commands to use fromAppendixA, then please contact
Data-LincGroupTechnicalservices for assistance.(Contact infromation is on page 14.)
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DATA-LINC GROUP
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DLM4500 User Guide
Technical Specifications
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DATA-LINC GROUP
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Technical Specifications Cont.
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DATA-LINC GROUP
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Technical Support
Data-LincGroupmaintains a fully trained staffofservice personnel who arecapableof providing complete product
assistance. They can provide you with technical, application, troubleshooting, and warranty assistance. Our technical staff is
basedinBellevue, Washington USAandmay be reachedat(425) 882-2206 ore-mail
[email protected]
Product Warranty
Data-LincGroupwarrants equipment ofits own manufacture tobe free from defectsin material and workmanshipfor one year
fromdate of shipmentto original user.Data-LincGroup will replaceor repair,at our option, any partfound to be defective.
Buyermust return any partclaimed defective to Data-LincGroup, transportation prepaid.
Return Material Authorization
If a part needs to be sent to the factory for repair, contact Data-Linc Group’s corporate office and request a Return Material
Authorization(RMA) number.The RMAnumber identifies thepartand the ownerand must beincluded with thepartwhen
shipped to the factory.
Contact Information
Corporate Office Data-Linc Group
3535Factoria Blvd. SE
Suite100
Bellevue,Washington98006USA
Telephone:[phone]
Fax:[phone]
E-mail:[email protected]
Website: www.data-linc.com

DATA-LINC GROUP
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DLM4500 User Guide
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Appendix A
Enclosure Dimensions
2.45 in
6.22 cm
Reference
9.00 in
22.86 cm
4.90 in
12.45 cm
2.75 in
6.99 cm
Slot Center
Reference
1.08 in
2.74 cm
4 Places
Ø 0.25 in
64 cm
Two Places
1.00 in
2.54 cm
4 Places
8.30 in
Center Reference
1.54 in
3.94 cm 0.06 in
.15 cm
7.75 in
19.69 cm
0.35 in
.89 cm
4 Places
21.08 cm

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Appendix B
AT Commands, S-Registers and Result Codes
TheAT commands are used to control the operation of your modem.They are calledATcommands because the characters
AT must precede each command to get the attention of the modem.
AT commands can be issued only when the modem is in command mode or on-line command mode. The modem is in
command mode whenever it is not connected to another modem. The modem is in data mode whenever it is connected to
another modem and ready to exchange data. On-line command mode is a temporary state in which you can issue
commands to the modem while connected to another modem. To put the modem into on-line command mode from data
mode, you must issue an escape sequence (+++). To return to data mode from on-line command mode, you must issue
thecommandATO.
To sendAT commands to the modem you must use a communications program, such as the HyperTerminal, an application
in Windows, or some other available terminal program. You can issue commands to the modem either directly, by typing
them in the terminal window of the communications program, or indirectly, by configuring the operating system or
communications program to send the commands automatically. Fortunately, communications programs make daily
operation of modems effortless by hiding the commands from the user. Most users, therefore, need to useAT commands
onlywhen reconfiguringthe modem,e.g., to turn auto-answer on or off.
Theformat for entering anATcommand isATXn,where Xis the command and n is the specific value for the command,
sometimes called the command parameter. The value is always a number. If the value is zero, you can omit it from the
command; thus,AT&W is equivalent toAT&W0. Most commands have a default value, which is the value that is set at the
factory.
You must press ENTER (depending on the terminal program it could be some other key) to send the command to the
modem.Any time the modem receives a command it sends a response known as a result code. The most common result
codes are OK, ERROR, and the CONNECT messages that the modem sends to the computer when it is connecting to
another modem. For a table of valid result codes, see “Result Codes” at the end of this appendix.
You can issue several commands in one line, in what is called a command string.The command string begins withAT and
ends when you press ENTER. Spaces to separate the commands are optional; the command interpreter ignores them.The
most familiar command string is the initialization string, which is used to configure the modem when it is turned on or
reset,or when your communications software calls another modem.

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AT Commands
ATAttention Code
Values: n/a
Description: The attention code precedes all command lines except A/, A:, and escape sequences.
ENTERKey
Values: n/a
Description: Press the ENTER (RETURN) key to execute most commands.
A Answer
Values: n/a
Description:Answer call before final ring.
A/ Repeat Last Command
Values: n/a
Description: Repeat the last command string. Do not precede this command with AT. Do not press
ENTERto execute.
B
n Communication Standard Setting
Values: n = 0–3, 15, 16
Default:1 and 16
Description: B0 Select ITU-TV.22 mode when modem is at 1200 bps.
B1 Select Bell 212A when modem is at 1200 bps.
B2 Deselect V.23 reverse channel (same as B3 ).
B3 Deselect V.23 reverse channel (same as B2 ).
B15 Select V.21 when the modem is at 300 bps.
B16 Select Bell 103J when the modem is at 300 bps.
D s Dial
Values: s = dial string (phone number and dial modifiers)
Default:none
Description: Dial telephone number s , where s may up to 40 characters long and include the 0–9, *,#, [ ] (space), B, C,
and D characters, and the L, P, T, V, W, S, [,](comma), [;](semicolon), !, @, ^and $ dial string modifiers.
Dial string modifiers:
L Redial last number. (Must be placed immediately after ATD.)
P Pulse-dialfollowing numbers in command.
T Tone-dialfollowing numbers incommand(default).
V Switch to speakerphone mode and dial the following number. Use ATH command to hang up.
W Wait for a new dial tone before continuing to dial. (X2, X4, X5, X6, or X7 must be selected.)
, Pause during dialing for time set in register S8.
; Return to command mode after dialing. (Place at end of dial string.)
! Hookflash. Causes the modem to go on-hook for one-half second, thenoff-hook again.
@Wait for quiet answer. Causes modem to wait for a ringback, then 5 seconds of silence, before processing next part of
command. If silence is not detected, the modem returns a NOANSWER code.
^ Disable data calling tone transmission.
$DetectAT&T call card “bong” tone. The character should follow the phone number and precede the user’s call card
number:ATDT1028806127853500$123456789

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DS=y Dial Stored Telephone Number
Values: n = 0–2
Default:none
Description: Dial a number previously stored in directory number y by the &Zy=x command.
Example: ATDS=2
En Echo Command Mode Characters
Values: n = 0 or 1
Default:1
Description: E0 Do not echo keyboard input to the terminal.
E1 Do echo keyboard input to the terminal.
Fn Echo Online Data Characters
Values: n = 1
Default:1
F0Enable online data character echo. (Not supported.)
F1Disable onlinedata characterecho (included for backward compatibility with some software).
Hn Hook Control
Values: n = 0 or 1
Default:0
Description:H0 Go on-hook(hang up).
H1Go off-hook(make thephone linebusy).
In Information Request
Values: n = 0–5, 9, 11
Default:None
Description:I0 Display default speed and controller firmwareversion.
I1 Calculate and display ROM checksum (e.g., 12AB).
I2 Check ROM and verify the checksum, displaying OK or ERROR.
I3Display default speed andcontroller firmware version.
I4Display firmware versionfor data pump(e.g., 94).
I5Display the boardID: software version, hardwareversion, and countryID
I9 Display the country code (e.g.,
NA Ver. 1 ).
I11 Display diagnostic information for the last modem connection, such as DSP and firmware version, link type, line speed,
serial speed, type of error correction/data compression, number of past retrains, etc.
M n Monitor Speaker Mode
Values: n = 0, 1, 2, or 3
Default:1
Description:M0 Speaker always off.
M1 Speaker on until carrier signal detected.
M2Speaker always on when modem is off-hook.
M3 Speaker on until carrier is detected, except while dialing.
N n Modulation Handshake
Values: n = 0 or 1
Default:1
Description: N0 Modem performs handshake only at communication standard specified by S37 and the B command.
N1 Modem begins handshake at communication standard specified by S37 and the B command.During handshake,
fallback to a lower speed can occur.