Westermo IDW-90 AT User Manual

AT Commands 

Interface Guide

6620-3200

IDW-90

Westermo Teleindustri AB 

©

ISDN

Terminaladapter

www.westermo.com

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1. Introduction

The Westermo IDW-90 is an industrialised ISDN Terminal adapter. This Terminal adapter 
has been developed with high speed industrial data communications in mind and has 
some features you would not expect to find on normal adapters.
    The unit is DIN rail mounted and has both an RS-232/V.24 and RS-485 interfaces with  
2 or 4 wire connections.
    Terminal data rates of up to 115.2 kbit/s can be handled with a 128 kbit/s ISDN

B-channel bit rate

The IDW-90 has been designed to meet the European ISDN standard DSS1.  
All standard ISDN transport protocols are supported including HDLC transparent,  
X75, PPP and ML-PPP.  
    V.110 asynchronous is supported with flow control at data rates up to 19.2 kbit/s. 
A watchdog facility continually monitors the power supply and internal hardware as well 
as the operational software. In the event of a problem the modem automatically resets. 
This feature has been included to make the unit more suitable for use in unmanned  
locations.

The IDW-90 is available in an LV version 

The nominal input voltage is 12–48 VDC ±10%.

The IDW-90 has 1 Digital opto-coupled input that can be used to trigger services  
specified in a list of service entries. The IDW-90 also has a relay output with change  
over contact. The relay output can be controlled from a remote Westermo modem 
(PSTN, GSM and ISDN).

The IDW-90 features DIP-switch configuration and can be programmed using  
AT-commands or a Configurator which allows local and remote configuration and  
CAPI 2.0 compatibility. It also has an internal analogue V.34 modem enabling connections  
from ISDN to analogue modem end locations.

The IDW-90 documentation includes extensive information on the command set,  
S registers, DIP-switches and error codes. Please call your local Westermo office if  
you need further technical information.

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1.1 LED Indicators

LED  Function  Description

L1  ISDN Line status   LED normally showing the status of the ISDN S

L1 together with L2 is also used to indicate error conditions  
in the IDW-90 and the connection to the ISDN S0 interface.

L2  ISDN Data connection  LED Normally showing the state of the data connection

ANL  Analogue line   OFF = No analogue connection established 

BLINK = Analogue call in progress 
ON = Analogue line established

TD  Transmit Data   LED showing data from the DTE, the LED will blink when  

data received

RD  Receive Data   LED showing data transmitted to the DTE, the LED will blink 

when data transmitted

RTS  Request to Send   LED showing the status of the handshake line RTS from DTE, 

LED is ON when DTE requests to send data

DCD  Data Carrier Detect   LED showing the status of the handshake line DCD from  

IDW-90, The behaviour of the DCD-line is programmable,  
see configuration command cdcd

DTR  Data Terminal Ready  LED showing the status of the handshake line DTR

L1  L2  Status

ON  5 blink/s  Start up phase

ON  OFF  S0 connection OK

ON  1 short blink/s  Call setup in progress

ON  1 long blink/s   Waiting for B channel synchronization

ON  ON  Data connection is established

OFF  OFF  No power or Hardware error

0.5 sec ON  OFF  Faulty or no S0 connection 

0.5 sec OFF

OFF  2 blink/s  IDW-90 internal RAM error

OFF   0.5 sec ON  IDW-90 internal ROM error 

0.5 sec OFF

 interface.   

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2. DIP-Switch Setup

The IDW-90 DIP-switches will be read at Power on and override the current  
database setting.

If an AT-command or Configurator command given after Power on is addressing  
the same parameter as a DIP-switch setting, the command will in turn override  
the DIP-switch setting.

To store the current DIP-switch setting use the configurator command save or AT&W.

3. Factory settings

Throughout this manual the default factory settings of parameters are shown with bold 
typeface and labelled (default) where applicable.

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4.  AT-command set

All parameters can be changed by using an extended AT command set described  
in this chapter. 
Check to see whether the factory setting will fit your environment.  
The factory setting is described (highlighted) in the parameter list shown below.
If you want a different configuration from the factory default setting, take the following 
steps:

…   Connect the IDW-90 to ISDN interface.
…   Connect the PC’s COM port to the DTE interface of the IDW-90.
…   Connect the power supply to the mains socket.
…   Start a terminal emulation on your PC, and verify that the baudrate setting

of the terminal emulation fits that of the IDW-90.

…   Set up the parameters of the IDW-90 from the terminal emulation and save  

the parameters using the AT command set.

Example:

To change the used B channel protocol to X.75 please enter the following commands:
  AT**prot=10<CR>  (set protocol to X.75)
  AT&W<CR>  (save the new configuration)
  Leave your terminal emulation and start your application program.

With the exception of the command A/ (Repeat command) all commands begin with the 
prefix AT and AT!,-where the prefix-AT! is used to identify commands to the analogue 
modem. Commands are terminated with <CR>. Corrections in a command line are done 
with <BACKSPACE>. A command line has a maximum of 240 characters. The command 
line is automatically cancelled by longer input. Blanks are ignored, capital/small letters are 
not significant.

The parameter settings of the IDW-90 obtained when using the-AT commands can be 
permanently stored (AT&W) and are not lost by resetting or by leaving the-AT command 
mode.

To enter the AT command mode during an active data connection you must use  
the following sequence (“Escape sequence”):
  at least 1 sec pause  <+><+><+> 1 sec pause.
The time gap between all three plus signs may not exceed 1 sec. 
The escape sequence is transmitted transparently to the remote device.

Note:   If B channel protocol PPPasync (AT**prot=3) is selected, the escape sequence  

has to be included in an asynchronous HDLC frame. The coding of the complete 
asynchronous sequence is: 7E 2B 2B 2B 1B B4 7E.

AT-command  Description

A/   Repeat last command line 

A   Accept incoming call 

##An   Only analogue outgoing call

B    B channel protocol  

(no function use IDW-90+Configurator command PROT)

%B   Set local baudrate 

CONF   Enter IDW-90+Configurator 

&C   DCD control 

#C   Received bearer service 

#C1=hbhb   Select bearer service outgoing 

#C2=hbhbhbhb  Select bearer service incoming 

!%C   Enable/Disable Data Compression 

D   Initiate outgoing call 

&D   DTR control 

!+DS   Data Compression 

E   Local echo 1

!%E   Enable/Disable Line Quality Monitor and Auto Retrain or Fallback/Fall Forward

!+ES   Error Control 

&F  Load factory defaults ISDN

!&F   Load factory defaults analogue option

H   Disconnect

#H   Display msn

I   Display version information

!I   Display version information for analogue modem.

&K   Flow control

!K  MNP Extended Services

!%L   Report Line Signal Level

#M   Received CLID

!+MS   Modulation Selection 

N   Set line baudrate V.110 (no function use IDW-90+Configurator command BRN)

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AT-command  Description

!\N   Operating Mode

O   Return to online state

#O   Received CLIP

Q   Suppress result

!%Q   Report Line Signal Quality

&R   CTS control

#R   Handle incoming calls

S   Display and set internal S register

&S   DSR control

V   Result format

&V   Display configuration

!&V1   Display Last Connection Statistics

W   Enhance result messages

&W   Store active configuration

!&W   Store active configuration for analogue modem

X   Reduce result messages

Z   Load stored settings

&Z   Store call number

#Z   Define own msn

**<cmd>   Execute configuration command 

!#UD   Last Call Status Report

Windows2000 AT command set change:
ATNxxx   All commands ATNxxx will respond OK without any functionality

behind it. V.110 baudrates can be set with AT**BRN.

ATBxxx   All commands ATBxxx will respond OK without any functionality 

behind it.  
The B-channel protocol settings can be set with AT**PROT.

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A/ – Repeat last command line

This command repeats the commands of the last entered command line.
Note: No prefix AT is required.
  A/

##An – Only analogue outgoing call 

Forces the IDW-90 to make analogue calls even if no control character (’#’ or ’!’) 
is used in the dial string.
This also implies that no digital outgoing call can be made when AT##A1 is set. 
Digital incoming calls can still be received.

  AT##A0:   configures the adapter to be able to make both analogue  

and digital outgoing calls. (default)

  AT##A1:  configures the adapter only to make analogue outgoing calls.

A – Accept incoming call

Using this command you can accept an incoming call, if automatic call acceptance is  
not set (Register S0 = 0). An incoming call is displayed by the message “RING” or  
the code “2”.
Must be the last command in an AT command line.
ATA

B – B channel protocol

This command  will respond with OK without any functionality after it. The B-channel 
protocol settings can be set with AT**prot.

%B – Set local baudrate

Sets the local baudrate of the IDW-90 to the desired value (fixed value) or to auto­detection. When autodetection is set, the IDW-90 will recognize the desired baudrate 
with every newly entered AT command by the terminal equipment (PC). With all other 
settings the PC must use the same baudrate.
Must be the last command in an AT command line.
  AT%B0  Automatic local baudrate detection enabled (autobauding, default)
  AT%B1  Local baudrate set to 1 200 bit/s
  AT%B2  Local baudrate set to 2 400 bit/s
  AT%B3  Local baudrate set to 4 800 bit/s
  AT%B4  Local baudrate set to 9 600 bit/s
  AT%B5  Local baudrate set to 19 200 bit/s
  AT%B6  Local baudrate set to 38 400 bit/s
  AT%B7  Local baudrate set to 57 600 bit/s
  AT%B8  Local baudrate set to 115 200 bit/s
  AT%B9  Local baudrate set to 230400 bit/s

Note:   Autobauding (AT%B0) is available for AT command set only.  

If autobauding is selected and no AT-command has been sensed  
before an incoming call baudrate 9600 will be used.

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CONF – Enter IDW-90+Configurator

Enters directly into the IDW-90+Configurator, the configuration prompt “#”  
will be displayed. Leave the IDW-90+Configurator with the command “quit”.
  ATCONF
Note:   During the change between the command sets from "AT command set" to

"configuration command set" the serial status line DSR becomes inactive.

#C – Received bearer service

Shows the bearer service that is received with an incoming call in hexadecimal coding 
hbhb.
The value for hbhb (word) is the CIP value as defined in the CAPI 2.0 specification.
  AT#C

#C1=hbhb – Select bearer service outgoing

Selects the bearer service that will be sent with an outgoing call
The value for hbhb (word) is the CIP value as defined in the CAPI 2.0 specification 
(default 0002).
  Example: an outgoing call as a data call:-AT#C1=0002.
  Example: an outgoing call as a voice call:-AT#C1=0004.

#C2=hbhbhbhb – Select bearer service incoming

Selects the bearer services that can be accepted with an incoming call.  
The definition of hbhbhbhb (double word) is the CIP mask as defined in the  
CAPI 2.0 specification
(default 00010016).

  Example:   AT#C2=00010016: Accept analogue incoming calls 

AT#C2=00000001: Accept all incoming calls.

Note:  Before issuing an outgoing call the command AT#C1 has to be set. 

To use the predefined services please setup factory defaults (AT&F).

!%C – Enable/Disable Data Compression

Enables or disables data compression negotiation for connection to PSTN.  
The modem can only perform data compression on an error corrected link.
The parameter value, if valid, is written to S41 bits 0 and 1.

AT!%C<value>
  0  Disables data compression. Resets S46 bit 1.
  1  Enables MNP 5 data compression negotiation. Resets S46 bit 1.
  2  Enables V.42 bis data compression. Sets S46 bit 1.
  3   Enables both V.42 bis and MNP 5 data compression. Sets S46 bit 1.

(default)

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&C – DCD control

Selects the behaviour of the DCD control line from the IDW-90.
  AT&C0  IDW-90 control line DCD is always ON
  AT&C1   DCD ON indicates ISDN or PSTN connection is established

and synchronized (default)
  AT&C2  DCD follows DTR
  AT&C3  DCD indicates link level established (X.31-D only)

 D – Initiate outgoing call

Dials the number (D for Dial). The dial modifier “W", “>”, “T”, “;”, “@” can be freely 
inserted in the dial string; they have no influence on the dial procedure of the IDW-90.
Must be the last command in AT command line.
Any character input while the IDW-90 is dialling will cancel the dialling procedure exept 
when dabort=0.

ATD<CALLEDnumber>[/<subaddr>]
[,X[Pxxx-][R ][N<nuipwd> ][G<cug> ]<X25number>]]

  CALLEDnumber:   ISDN call number for a dialled B channel connection or X.25 

number for X.31 D channel
  Subaddr   dialled sub address
  P:   use packet size xxx for X.25 connection (value from 64 – 2048)
  R:   request the facility reverse charging
  G:   access to X.25 closed user group
  O:   Outgoing call from X.25 closed user group
  N:    use NUI and password with call setup allowed chars: a-z, A-Z, 0-9.

(Overrides setting of nui configuration command)
  X25number:   dialled X.25 call number (X.25 B channel only)
  ATDL  Dial the last dialled number
  ATDS=n     Dial number n from stored telephone number list (n = 1..3)

(See command AT&Z to store numbers)

AT!D<PSTNnumber> 
  ATD#<PSTNnumber>
  ATDT#<PSTNnumber>

  PSTNnumber:   Call number for a dialled connection to an analogue PSTN  

number over ISDN using the internal analogue modem
  AT!DL  Dial the last dialled number
  AT!DS=n   Dial number n from stored telephone number list (n = 1..3)

(See command AT&Z to store numbers) and catab n

Notes:  – To setup the own sub address see configuration command sub.

ATD<CALLEDnumber>e

Adding an “e” to CALLEDnumber indicates that a connection to the internal remote 
access of an IDW-90 shall be performed, the protocol X.75 (ATB10) has to be used. 
Remote configuration can also be accessed through sending the remote access escape 
sequence  ´++++’. See section 5.5

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Examples for X.25 and X.31 calls:

ATD12345678<cr>
  X.31:  dial X.25 number 12345678
  X.25-B:  dial ISDN call to 12345678 without a specific X.25 number

ATD12345678X4000123456<cr>
  X.31:  ISDN number 12345678 will be ignored if X.25 number is set
      dial X.25 number 4000123456
  X.25-B:  dial ISDN call to 12345678
      with X.25 number 4000123456

ATD12345678XP64,R,O02,Nnuivalue,4000123456<cr>
  X.25-B:  dial ISDN call to 12345678
      with packet size 64 byte
      with active reverse charging
      with outgoing call from closed user group "CUG" 02
      with NUI selection string "nuivalue"
      with X.25 number 4000123456

&D – DTR control

Selects the behaviour of the IDW-90, when the DTE control line DTR changes from  
ON to OFF.
  AT&D  DTE control line DTR setting is ignored
  AT&D2   DTR is evaluated: dropping the DTR line by the DTE will disconnect

an existing ISDN connection. An incoming call will accepted only 
with DTR active. (default)

  AT&D4   DTR is evaluated: Incoming calls will be accepted independent of 

DTR status; DTR drop disconnects an active connection

For nearer information see also chapter 4.3 Serial status lines. 

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!+DS – Data Compression

This extended-format compound parameter controls the V.42bis data compression func­tion if provided in the modem. It accepts four numeric sub parameters:

  AT!+DS=[<direction>[,<compr_neg>[,<max_dict>[,<max_string>]]]]

  <direction>   Specifies the desired direction(s) of operation of the data compres-

sion function; from the DTE point of view. 
0  Negotiated; no compression (V.42bis P0=0). 
3  both directions, accept any direction (V.42bis P0=11) (default)

  <compr_neg>   Specifies whether or not the modem should continue to operate if 

the desired result is not obtained.

    0   Do not disconnect if V.42bis is not negotiated by the remote 

modem as specified in <direction>
  <max_dict>   Specifies the maximum number of dictionary entries (2 048 entries)

which should be negotiated (may be used by the DTE to limit the 
codeword size transmitted, based on its knowledge of the nature of 
the data to be transmitted).

  <max_string>   Specifies the maximum string length (32 bytes) to be negotiated 

(V.42bis P2).

Reporting Current or Selected Values

Command:  AT!+DS?
  Response:  +DS: <direction>,<compr_neg>,<max_dict>,<max_string>

  Example:  +DS: 3,0,2048,32 for the defaults and 2048 entry max dictionary

Reporting Supported Range of Parameter Values

Command:  AT!+DS=?
  Response:   +DS: (<direction>range),(<compr_neg>range), (<max_

dict>range),(<max_string>range)

  Example:  +DS: (0,3),(0),(2048),(32)

E – Local echo

Selects the local echo in command mode.
  ATE0  No local echo
  ATE1  Local echo on in command phase (default)

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!%E – Enable/Disable Line Quality Monitor and Auto-Retrain  
or Fallback/Fall Forward

Controls whether or not the modem will automatically monitor the line quality and 
request a retrain (%E1) or fall back when line quality is insufficient or fall forward when 
line quality is sufficient (%E2). The parameter value, if valid, is written to S41 bits 2 and 6. 
If enabled, the modem attempts to retrain for a maximum of 30 seconds.

AT!%E0   Disable line quality monitor and auto-retrain.
  AT!%E1   Enable line quality monitor and auto-retrain.
  AT!%E2   Enable line quality monitor and fallback/fall forward. (default)

Fallback/Fall Forward. When %E2 is active, the modem monitors the line quality 
(EQM). When line quality is insufficient, the modem will initiate a rate renegotiation to a 
lower speed within the V.34/V.32 bis/V.32 modulation speeds. The modem will keep falling 
back within the current modulation if necessary until the speed reaches 2 400 bit/s (V.34) 
or 4 800 bit/s (V.32). Below this rate, the modem will only do retrains if EQM thresholds 
are exceeded. If the EQM is sufficient for at least one minute, the modem will initiate 
a rate renegotiation to a higher speed within the current modulation speeds. The rate 
renegotiations will be done without a retrain if a V.32 bis connection is established.
Speeds attempted during fallback/fall forward are those shown to be available in the rate 
sequences exchanged during the initial connection. Fallback/fall forward is available in 
error correction and normal modes, but not in direct mode.

!+ES – Error Control 

This command specifies the initial requested mode of operation when the modem is 
operating as the originator, optionally specifies the acceptable fallback mode of operation 
when the modem is operating as the originator, and optionally specifies the acceptable 
fallback mode of operation when the modem is operating as the answerer. It accepts 
three numeric sub parameters:

AT!+ES=[<orig_rqst>[,<orig_fbk>[,<ans_fbk>]]]

  <orig_rqst>   Decimal number which specifies the initial requested mode of opera-

tion when the modem is operating as the originator. The options are:
  0  Not supported.
  1   Initiate call with Normal Mode

(also referred to as Buffered Mode) only.
  2   Initiate V.42 without Detection Phase. If V.8 is in use, disable V.42

Detection Phase.
  3  Initiate V.42 with Detection Phase. (default)
  4  Initiate MNP.
  6  Not supported.
  7   Initiate Frame Tunnelling Mode when connection is complete, and

Data Mode is entered.

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  <orig_fbk>   Decimal number which specifies the acceptable fallback mode of  

operation when the modem is operating as the originator.
  0  LAPM, MNP, or Normal Mode error control optional. (default)
  1  Not supported.
  2   LAPM or MNP error control required; disconnect if error control

is not established. 
  3   LAPM error control required; disconnect if error control is not

established. 
  4   MNP error control required; disconnect if error control is not

established.
  <ans_fbk>   Decimal number which specifies the acceptable fallback mode of

operation when the modem is operating as the answerer or specifies 

V.80 Synchronous Access Mode.
  0  Not supported.
  1  Error control disabled, use Normal Mode.
  2  LAPM, MNP, or Normal Mode error control optional. (default)
  3  LAPM, MNP, or Direct Mode error control optional.
  4   LAPM or MNP error control required; disconnect if error control

is not established.
  5   LAPM error control required; disconnect if error control is not

established.
  6   MNP error control required; disconnect if error control is not

established.
  8  Not supported.
  9  Not supported.

Example:
  AT! +ES=3   Enable V.42 with Detection Phase originator.

Disable V.80 Synchronous Access Mode originator. 
  AT!+ES=,,2   Allow LAPM, MNP, or Normal Mode connection answerer.

Disable V.80 Synchronous Access Mode answerer.
  AT!+ES=3,,2  Enable V.42 with Detection Phase originator, allow LAPM, MNP,

or Normal Mode connection answer. 

Disable Synchronous Access Mode originator and answerer.

Reporting Current or Selected Values

Command:  AT!+ES?
  Response:  +ES: <orig_rqst>,<orig_fbk>,<ans_fbk>
  Example:  +ES: 3, 0, 2   For default settings.

Reporting Supported Range of Parameter Values

Command:  AT!+ES=?
  Response:  +ES: (<orig_rqst> range),(<orig_fbk>range),(<ans_fbk>range)
  Example:  +ES: (0-4, 6, 7), (0-4), (0-6, 8, 9)

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&F – Load factory defaults

Factory default will be loaded, ISDN protocol setting and msn’s will not be overwritten. 
(for storing in non volatile memory please use the command AT&W).
  AT&F0  Setup all parameters concerning data port
  AT&F1  Setup all parameters including ISDN protocol and msn settings.

!&F – Load factory defaults

Factory default will be loaded for the analogue option  
(for storing in non volatile memory please use the command AT!&W).
  AT!&F  The analogue modem loads the factory default configuration (profile)

H – Disconnect

Disconnects existing ISDN data connection, after issuing the Escape sequence (+++).
To enter the ATH command during an active data connection you must use the follow­ing sequence "<1 sec pause> <+><+><+> <1 sec pause>" to reach the online command 
mode.
The time gap between all three plus signs may not exceed 1 sec. 
The escape sequence is transmitted transparently to the remote device.

   The timeout after sending the "escape sequence" <+><+><+> will increase if the 

configuration parameter "txfwd" will rise. The default value of "txfwd" is set to "0".

I – Display version information

Displays different information about version number and settings:
  ATI0   Returns the “Modem”-type; name of the terminal adapter (“IDW-

90“)
  ATI1  Returns internal checksum (“??”)
  ATI2  Returns “OK”
  ATI3  Returns version string: “410045vv” vv = version number.
  ATI4  Returns manufacturers name: “Westermo Teleindustri AB”
  ATI5  Returns ISDN selected D-Channel protocol: “0 – DSS1”
  ATI6  Returns copyright string: “(c) Copyright Westermo Teleindustri AB”
  ATI7   Returns the status of the IDW-90 configuration switches.
    1  1  1  1
    “00000000.00000000.00000000.00000000”
    SW1  SW2  SW3  SW4
    ‘0’ = switch OFF and ‘1’ = switch ON.
  ATI9  Returns plug and play ID string
  ATI99  Returns software version creation date

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!I – Display version information for analogue modem

Displays various information about version number and settings for the analogue modem:
  AT!I0  Reports product code,
  AT!I1   Reports the least significant byte of the stored checksum in decimal

(see firmware release notes). Reports 255 if the prestored checksum 

value is FFh.
  AT!I2  Reports “OK”.
  AT!I3   Reports identification codes in the form RevisionName-Modulation

where:
      RevisionName =Product family, CX06833.
      Modulation = V34 or V32

Example:  CX068330-V34
  AT!I4  Reports OEM Manufacturer string e.g.: Westermo IDW-90
  AT!I5  Reports Country Code parameter, e.g., 42.
  AT!I6  Reports modem data pump model and internal code revision
  AT!I7  Reports OK.

&K – Flow control

Selects the flow control behaviour of the IDW-90 while in data communication phase.
  AT&K0  No local flow control between the DTE and IDW-90 is used
  AT&K3    Local flow control is set to hardware handshake RTS/CTS (default)
  AT&K4     Local flow control is set to software handshake XON/XOFF

!-K – MNP Extended Services

Enables or disables conversion of a V.42 LAPM connection to an MNP 10 connection.  
The parameter value, if valid, is written to S40 bits 0 and 1.
  AT!-K0  Disables V.42 LAPM to MNP 10 conversion. (default)
  AT!-K1  Enables V.42 LAPM to MNP 10 conversion.
  AT!-K2   Enables V.42 LAPM to MNP 10 conversion; inhibits MNP Extended

Services initiation during V.42 LAPM answer mode detection phase.

!%L – Report Line Signal Level

Returns a value which indicates the received signal level. The value returned is a direct 
indication of the receive level at the MDP, For example, 009 = –9 dBm, 043 = –43 dBm, 
and so on. This command is only valid in online command mode.

#M – Received CLID

Shows the called line identification (CLID) that is received with an incoming call – this is 
the number of the called party addressed on the local S-bus (selected msn).
  AT#M

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! +MS – Modulation Selection

This command parameter controls the manner of operation of the modulation capabili­ties in the modem. It accepts six sub parameters:
AT!+MS=[<carrier>[,<automode>[,<min_tx_rate>[,<max_tx_rate>[,<min_rx_rate>
[,<max_rx_rate>]]]]]]
Where: Possible <carrier>,  <min_tx_rate>, <max_tx_rate>, <min_rx_rate>, and <max_rx_
rate> values are listed below.

!+MS Command Supported Rates

Modulation  <carrier>   Possible (<min_rx_rate>, <max_rx_rate>,  ( <min_tx_rate>)  

and <max_tx_rate>) Rates (bit/s)

Bell 103  B103  300
Bell 212  B212  1 200 Rx/75 Tx or 75 Rx/1 200 Tx
V.21  V21  300
V.22  V22  1 200
V.22 bis  V22B  2 400 or 1 200
V.23  V23C  1 200
V.32  V32  9 600 or 4 800
V.32 bis  V32B  14 400, 12 000, 9 600, 7 200 or 4 800
V.34  V34   33 600, 31 200, 28 800, 26 400, 24 000, 21 600, 19 200, 16 800,

14 400, 12 000,  9 000, 7 200, 4 800 or 2 400

Defined Values

  <carrier>   A string which specifies the preferred modem carrier to use in  

originating or answering a connection. <carrier> values are strings  
of up to eight characters, consisting only of numeric digits and 
upper case letters.

<carrier> values for ITU standard modulations take the form:  
<letter><1-4 digits><other letters as needed>.

  <automode>   A numeric value which enables or disables automatic modulation 

negotiation (e.g., ITU-T V.32 bis Annex A or V.8). 
0 = Automode disabled.

1 = Automode enabled. (default)
  <min_rx_rate>   Numeric values which specify the lowest (<min_rx_rate>) and  
         and  highest rate at which the modem may establish a receive connection.  
  <max_rx_rate>   May be used to condition distinct limits for the receive direction as

distinct from the transmit direction. Values for this sub parameter 

are decimal encoded, in units of bit/s. The possible values for each 

modulation are listed in Table 1. 

Actual values will be limited to possible values corresponding to 

the entered <carrier> and fall-back <carrier> as determined during 

operation. (default = lowest (<min_rx_rate>) and highest (<max_

rx_rate>) rate supported by the selected carrier.

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<min_tx_rate>   Numeric values which specify the lowest (<min_tx_rate>) and  
          and  highest (<max_tx_rate>) rate at which the modem may establish a  
  <max_tx_rate>   transmit connection. Non-zero values for this subparameter are

decimal encoded, in units of bit/s. The possible values for each 
modulation are listed in Table 1. 
Actual values will be limited to possible values corresponding to 
the entered <carrier> and fall-back <carrier> as determined during 
operation. (default = lowest (<min_tx_rate>) and highest (<max_
tx_rate>) rate supported by the selected carrier.)

Reporting Current or Selected Values

Command:  !+MS?
  Response:   +MS:  <carrier>, <automode>, <min_tx_rate>, <max_tx_rate>, <min_

rx_rate>, <max_rx_rate>

  Note:- The current active settings are reported under control of the !+MR  

parameter.

  Example:   !+MS=V90, 1, 300,   This example uses default values, allowing  

33 600, 300, 33 600  maximum system flexibility to determine  
       optimal receive and transmit rates during

operation.

Reporting Supported Range of Parameter Values

Command:  !+MS=?
  Response:   +MS: (<carrier> range), (<automode> range), (<min_tx_rate> range),

(<max_tx_rate> range), (<min_rx_rate> range), (<max_rx_rate> 
range)

  Example:   +MS: (B103, B212, V21, V22, V22B, V23C, V32, V32B, V34), (0,1),  

(300-33 600), (300-33 600)

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N – Set line baudrate V.110

This command will respond with OK without any functionality after it. V.110 baudrates 
can be set with AT**BRN.

!\N – Operating Mode

This command controls the preferred error correcting mode to be negotiated in a  
subsequent data connection. 
  AT!\N0   Selects normal speed buffered mode

(disables error-correction mode). 
  AT!\N1  Same as !\N0
  AT!\N2   Selects reliable (error-correction) mode. The modem will first

attempt a LAPM connection and then an MNP connection. Failure  

to make a reliable connection results in the modem hanging up. 

(Forces !&Q5, S36=4, and S48=7.)
  AT!\N3   Selects auto reliable mode. This operates the same as \N2 except

failure to make a reliable connection results in the modem falling 

back to the speed buffered normal mode. (Forces S36=7, and S48=7, 

(default)
  AT!\N4   Selects LAPM error-correction mode. Failure to make an LAPM

error-correction connection results in the modem hanging up. 

(Forces S48=0.)  

Note: The !-K1 command can override the !\N4 command.
  AT!\N5   Selects MNP error-correction mode. Failure to make an MNP

error-correction connection results in the modem hanging up.  

(Forces S36=4, and S48=128.)

O – Return to online state

If the IDW-90 is in command mode after issuing an escape sequence out of an existing 
connection, ATO brings the IDW-90 back to data phase.
Must be the last command in AT command line.
  ATO

#O – Received CLIP

Shows the calling line identification (CLIP) that is received with an incoming  
call – number of the calling party.
  AT#O

Q – Suppress result

Suppresses result codes.
  ATQ0  Return status – codes after command input (default)
  ATQ1  No result codes are returned

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!%Q – Report Line Signal Quality

Reports the line signal quality. Returns the higher order byte of the EQM value. 
Based on the EQM value, retrain or fallback/fall forward may be initiated if enabled 
by !%E1 or !%E2.
Only valid in online command mode.

&R – CTS control

Selects the behaviour of the CTS control line from the IDW-90.
  AT&R0  IDW-90 control line CTS is following all changes of RTS
  AT&R1  CTS is always ON (default)
  AT&R2  CTS follows DTR
For nearer information see also chapter 4.3 Serial status lines

S – Display and set internal S register

ATSnn?  Show actual values (decimal) of selected register nn
  ATSnn=xx  Set selected register nn to the decimal value xx.

&S – DSR control

Selects the behaviour of the DSR control line from the IDW-90.
  AT&S  TA control line DSR is always ON (default)
  AT&S1  DSR ON indicates ISDN connection is established and synchronized
  AT&S5  DSR ON indicates an active ISDN call procedure (off hook) 
For further information see also chapter 4.3 Serial status lines

V – Result format

ATV0  Result is presented as numbers (followed by <CR>)
  ATV1  Result is presented as text (default)
  ATV2  Result is presented as text 
     RING and CONNECT including ISDN address, all others include

error causes

&V – Display configuration

  AT&V0   Displays the actual configuration of AT command setting including 

stored ISDN numbers

  AT&V1   Displays the actual configuration of IDW-90+Configurator command 

setting.

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!&V1 – Display Last Connection Statistics
Displays the last connection statistics in the following format (shown with typical results):

TERMINATION REASON
LAST TX rate

.... 26400 BIT/S

HIGHEST TX rate
LAST RX rate

.... 33600 BIT/S

HIGHEST RX rate
PROTOCOL
COMPRESSION
Line QUALITY
Rx LEVEL

....... LAPM

.... V42Bis

... 038

........ 015

Highest Rx State
Highest TX State
EQM Sum
Min Distance
RBS Pattern
Rate Drop
Digital Loss

......... 00B4

.... 0000

..... 00

....... 00

.... 2000

Local Rtrn Count
Remote Rtrn Count

LOCAL REQUEST

. 26400 BIT/S

. 33600 BIT/S

67
67

00

00

Flex 9481814347C4

RBS Pattern:  Shows which bits are being robbed in the least significant 6 bytes, e.g.,  

03 indicates 2 robbed bits in bit positions 0 and 1.

Digital Loss:   Shows if a pad was encountered and if so, what was the digital loss.  

2000 means 0dB.

W – Enhance result messages

  ATW0    Shows result code (RING, CONNECT) without additional info 

(default)
  ATW1    Result is presented with extended result codes

RING and CONNECT including ISDN address, all others include 

error causes. 

Message RINGING will be displayed with an outgoing call.

&W – Store active configuration

The active configuration will be stored in non volatile memory.
  AT&W0
  AT!&W

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21

!&W – Store active configuration

The active configuration for the analogue modem will be stored in non volatile memory.
AT!&W
X – Reduce result messages
Reduces the number of result messages after trying to set up a connection
  ATX0  “CONNECT” only
  ATX1  “CONNECT” with line speed, “BUSY”, “NO DIALTONE” not used
  ATX2  “CONNECT” with line speed, “BUSY” not used
  ATX3  “CONNECT” with line speed, “NO DIALTONE” not used
  ATX4  “CONNECT” with line speed, all messages used (default).

Z – Load stored settings

The active configuration will be replaced by the stored configuration.
Must be the last command in an AT command line.
  ATZ
This command will also cause a soft reset of the analogue modem with a recall of stored 
configuration profile.

&Z – Store call-number

Stores dialling number nn as entry number x into the telephone list (x = 1..3).
  AT&Zx=nn  set entry number x to dialling number nn
  AT&Zx  shows entries number x.
  AT&Z  show all entries.

#Z – Define own msn

Defines the msn nn for the data port.
If the number is set to “*“ (default), all incoming calls are acceptable.
The msn can be displayed by command AT#H or AT&V1.
  AT#Z=nn
The msn is automatically stored to non volatile RAM.

**<cmd> – Execute configuration command

Executes one configuration command, for definition of commands  
see IDW-90+Configurator commands section.
  AT**<cmd>

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Table 1 S-registers

Register  Function  Range  Units  Saved  Default  Note

S0  Rings to Auto-Answer   0–255   rings   *  1

S1  Ring Counter   0–255   rings    0

S2  Escape Character ASCII   0–255  ASCII  *  43 (02Bh)

S3   Carriage Return Character   0–127   ASCII  *  13 (0Dh)

S4  Line Feed Character   0–127  ASCII   *  10 (0Ah)

S5  Backspace Character   0–128  ASCII   *  8

S6  Dial delay  0–255  ASCII  *

S7    Wait Time for Carrier, Silence,  

S9   Enable PNP functionality  

S10   Lost Carrier To Hang Up Delay   1–255  0.1 s   *  14  PSTN

S16   Last occurred CAPI/ISDN  

S30   Disconnect inactivity timer  

S36   LAPM Failure Control   –   –   *  7  PSTN

S40    General Bit-Mapped Options  

S41    General Bit-Mapped Options  

S46   Data Compression Control   –   –   *  138  PSTN

S48   V.42 Negotiation Control   –   –   *  7  PSTN

S86    Analogue Call Failure  

S90   Last incoming ISDN calling  

S91    PSTN Transmit Attenuation Level   0–15  dBm   *  13  PSTN

S93   Unknown AT command handling  0,1  ASCII  *  0 

S210   V.34 Symbol Rate   0–255  –    13 (0Dh)  PSTN

* Register value may be stored in the user profiles with the &W command.

or Dial Tone  0-60  s  *  50

for Windows  0–1  ASCII     1

error cause  –   –      

See *idle  0-255  10s  *  0 

Status  –   –   *  104 (68h)  PSTN

Status  –   –   *  195 (C3h)  PSTN

Indication   0–26  –    21  PSTN

number (CLIP)  –   –      

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S0 – Number of Rings to Auto-Answer

S0 sets the number of the rings required before the modem automatically answers a call.
Setting this parameter to zero disables auto-answer mode.
  0   No automatic call acceptance, acceptance of an incoming call is controlled

by the data terminal (command ATA after RING)

  1  Immediate call acceptance by the terminal adapter (default)

  2..n   Call acceptance through the terminal adapter after n “RING ” messages.

  Note:  The time between two ring messages can be configured using the  

IDW-90-configuration command “ringtimer “(default =5 sec.)

S1 – Ring Counter

Ring Counter (read only), S1 is incremented each time the modem detects a ring signal.

S2 – Escape Character

S2 holds the decimal value of the ASCII character used as the escape character.
The default value 43 corresponds to an ASCII '+'..

S3 – Carriage Return Character

S3 sets the command line and result code terminator character. Default: 13 Carriage 
Return

S4 – Line Feed Character

S4 sets the character recognised as a line feed. The Line Feed control character is output 
after the Carriage Return control character if verbose result codes are used. Default: 10 
Line Feed.

S5 – Backspace Character

S5 sets the character recognised as a backspace. The terminal adapter will not recognise 
the Backspace character if it is set to a value that is greater than 128 ASCII. This charac­ter can be used to edit a command line. When the echo command is enabled, the modem 
echoes back to the local DTE the Backspace character, an ASCII space character and 
second Backspace character; this means a total of three characters are transmitted each 
time the modem processes the Backspace character.

Default: 8 (Backspace)

S6 – Dial delay

This S-register defines how many seconds the unit will delay a call attempt.
The timer starts counting after the ATD command has been sent to the adapter.

S7 – Wait time for Carrier

S7 sets the time the terminal adapter will wait for synchronization and also the time the 
analogue modem will wait for carrier. Default: 50 sec

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S9 – Enable PNP functionality for Windows

S9 enables and disables the Windows Plug and Play identification of the terminal adapter.
(default = 1, enabled)

S10 – Lost Carrier To Hang Up Delay (analogue)

S10 sets the length of time, in tenths of a second, that the analogue modem waits before 
hanging up after a loss of carrier. This allows for a temporary carrier loss without causing 
the local modem to disconnect. When register S10 is set to 255, the modem functions as 
if a carrier is always present.
The actual interval the modem waits before disconnecting is the value in register S10
minus 0.6s.
Therefore, the S10 value must be greater than 0.6s or else the modem disconnects 
before it recognises the carrier.
Range: 1 – 255 tenths of a second

Default: 14 (1.4 seconds)

S16 – Last ocurred CAPI/ISDN error cause

See Table 6  ISDN causes and their explanation (DSS1) 84 and Table 8 CAPI causes and 
their explanation.91

S30 – Disconnect Inactivity Timer

S30 sets the length of time, in tens of seconds, that the modem will stay online before 
disconnecting when no data is sent or received. In error-correction mode, any data trans­mitted or received will reset the timer. In other modes, any data transmitted will reset 
the timer.
Range: 0–255 tens of seconds (0–2 550 seconds) See configuration command “idle”.

S36 – LAPM Failure Control (analogue)

Bits 0 – 2 This value indicates what should happen upon a LAPM failure. These fallback 
options are initiated immediately upon connection if S48=128.If an invalid number is 
entered, the number is accepted into the register, but S36 will act as if the default value 
has been entered.
  0  Modem disconnects.
  1  Modem stays on-line and a Direct mode connection is established.
  2   Reserved.
  3   Modem stays on-line and a Normal mode connection is established.
  4   An MNP connection is attempted and if it fails, the modem disconnects.
  5    An MNP connection is attempted and if it fails, a Direct mode connection is

established.
  6   Reserved.
  7    An MNP connection is attempted and if it fails, a Normal mode connection

is established.(default)

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S40 – General Bit Mapped Options Status (analogue)

S40 indicates the status of command options.
  Default: 0 (00h) (00000000b)
  Bits 0 – 1   MNP Extended Services (-Kn)

0  Disable extended services (-K0) (default) 
    1  Enable extended services (-K1) 
    2   Enable extended services (-K2)

  Bits 2 – 7   Reserved.

S41 – General Bit Mapped Options Status (analogue)

S41 indicates the status of command options.
  Default: 195 (C3h) (1100011b)
  Bits 0 – 1   Compression selection (%Cn)
        0  Disabled (%C0 )
        1   MNP 5 (%C1)
        2  V.42 bis (%C2)
      3   MNP 5 and V.42 bis (%C3) (default)
  Bits 2,  6   Auto retrain and fallback/fall forward (%En)
        0 0  Retrain and fallback/fall forward disabled (%E0)
        0 1  Retrain enabled (%E1)
      1 0  Fallback/fall forward enabled (%E2) (default)
  Bits 3 – 5, 7   Reserved.

S46 – Data Compression Control (analogue)

S46 controls selection of compression. The following actions are executed for the given
values:
  S46
  136   Execute error correction protocol with no compression.
  138   Execute error correction protocol with compression. (default)

S48 –V.42 Negotiation Control (analogue)

The V.42 negotiation process determines the capabilities of the remote modem. However, 
when the capabilities of the remote modem are known and negotiation is unnecessary, 
this process can be bypassed if so desired.
  S48
  0   Disable negotiation; bypass the detection and negotiation phases; and

proceed with LAPM.
  7  Enable negotiation. (default)
  128    Disable negotiation; bypass the detection and negotiation phases; and

proceed at once with the fallback action specified in S36. Can be 

used to force MNP.

S86 – Call Failure Reason Code (analogue)

When the internal analogue modem issues a NO CARRIER result code, a value is writ­ten to S86 Register to help determine the reason for the failed connection. S86 records 
the first event that contributes to a NO CARRIER message. The S86 register is only 
updated when the NO CARRIER is sent as result from a broken connection to an ana­logue subscriber. The code definitions are:

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S86
  0  Normal hangup,no error occurred.
  1  Reserved.
  2  Reserved.
  3  Call Waiting caused disconnect.
  4   Physical carrier loss.
  5   No error correction at the other end.
  6  No response to feature negotiation.
  7   This modem is async only; the other modem is sync only.
  8   No framing technique in common.
  9  No protocol in common.
  10  Bad response to feature negotiation.
  11   No sync information from the remote modem.
  12   Normal hang-up initiated by the remote modem.
  13   Retransmission limit reached.
  14   Protocol violation occurred.
  15   Lost DTR.
  16   Received GSTN clear down.
  17   Inactivity timeout.
  18  Speed not supported.
  19  Long space disconnect.
  20  Key abort disconnect.
  21   Clears previous disconnect reason.
  22   No connection established.
  23   Disconnect after three retrains.
  24   Call Waiting tone detected.
  25  Extension pickup detected.
  26  Remote hang-up detected.

S90 – Last incoming ISDN calling number (CLIP)

S90 displays the ISDN line identification of the last incoming call.

S91 – PSTN Transmit Attenuation Level (analogue)

S91 sets the transmit attenuation level from 0 to 15 dBm for the PSTN mode, resulting 
in a transmit level from 0 to – 15 dBm.

Default: 13.

S93 – Unknown AT command handling

Controls the response to unknown AT-commands
  0   Undefined AT commands will be responded to with ERROR (default)
  1  Undefined AT commands will be responded to with OK

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27

S210 – V.34 Symbol Rates (analogue)

The bits in this parameter control V.34 symbols rates and enables/disables V.34  
asymmetric rates. This parameter is used for diagnostic purposes only.
  Bits 0 – 2 
  Selects the range of allowed V.34 symbol rates.
  Bit      Symbol Rates (baud)
  2  1  0 
  0  0  0  2 400 only
  0  0  1  2 400 only (no 2 734)
  0  1  0  2 400, 2 800
  0  1  1  2 400, 2 800, 3 000
  1  0  0  2 400, 2 800, 3 000, 3 200
  1  0  1  2 400, 2 800, 3 000, 3 200, 3 429 (default)
  Bit 3 
Enable/disable V.34 asymmetric rates.
    0 = Disable asymmetric rates
   1 = Enable asymmetric rates (default)
  Bits 4 – 7 Reserved.

  Default: 13.

Table 1 S-registers

Short Form  Long Form  Description  Note

0  OK   A command line has been executed

1   CONNECT <rn>   Connection established 

2  RING <rn>  Indicates an incoming call  (SETUP received)

3  NO CARRIER <xx>   No synchronization (xx = ISDN error cause)  

4  ERROR   Illegal command or error that can not be  

    3.   A command parameter within the command  

5  CONNECT  1 200 <rn>   A connection with a line speed of 1200 bit/s  

6  NO  DIALTONE <xx>  No access to ISDN network (xx = ISDN error)

7  BUSY<xx>  Number engaged (xx = ISDN error cause)

( rn = call number of remote site)

or if the the call was to an analogue destination. 
Replaces BUSY and NO DIALTONE.  
Dependent on ATXn setting. Also sent when  
the modem auto-disconnects due to loss of  
carrier.

indicated otherwise e.g.  

1. The command line contains a syntax error.  

2.  The modem cannot execute a command  
contained in the command line, i.e., the  
command does not exist or is not  
supported. see register S93

line is outside the permitted range.

has been established.  
(V110 or analogue connection)

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Table 2 cont.

Short Form  Long Form  Description  Note

8  NO ANSWER<xx>   No connection; called number can not be  

9  CONNECT 600 <rn>  Connection, line speed 600 bit/s.  1

11  CONNECT 4 800 <rn>   Connection, line speed 4 800 bit/s.  

12  CONNECT 9 600 <rn>   Connection, line speed 9 600 bit/s.  

13  CONNECT 7 200 <rn>  Connection, line speed 7 200 bit/s.  1

14  CONNECT 12 000 <rn>  Connection, line speed 12 000 bit/s.   1

15  CONNECT 14 400 <rn>  Connection, line speed 14 400 bit/s.  1

16  CONNECT 19 200 <rn>   Connection, line speed 19 200 bit/s.  

19  CONNECT 64 000 <rn>  Connection, line speed 64 000 bit/s. 

59  CONNECT 16 800 <rn>  Connection, line speed 16 800 bit/s  1

61  CONNECT 21 600 <rn>  Connection, line speed 21 600 bit/s  1

62  CONNECT 24 000 <rn>  Connection, line speed 24 000 bit/s  1

63  CONNECT 26 400 <rn>  Connection, line speed 26 400 bit/s  1

64  CONNECT 28 800 <rn>  Connection, line speed 28 800 bit/s  1

84  CONNECT 33 600 <rn>  Connection, line speed 33 600 bit/s  1

91  CONNECT 31 200 <rn>  Connection, line speed 31 200 bit/s  1

Note 1. Analogue modem result code.

reached (xx = ISDN error cause) or if the the  
call was to an analogue destination. The modem  
is attempting to originate a call if a continuous  
ringing signal is detected on the line until the  
expiration of the timer S7.

(V.110 or analogue connection)

(V.110 or analogue connection)

(V.110 or analogue connection)  1

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4.1 Call number display

In AT command mode, call number display (does not belong to the AT command stand­ard) can be turned on by issuing the command ATW1. If turned on, the call number of 
the caller is shown with the Connect- or Ring-message (in pointed brackets), depending 
on the signalling in D-channel.
If the IDW-90 is used with the public network then the call number of the remote site 
(including area code) is displayed.

Example:  TxD  RxD
    ATW1

OK
      RING <040890880>
    ATA
      CONNECT 64000 <040890880>

4.2 Error cause display

Example:  Tx data  Rx data
    ATW1

OK
    ATD12345
      NO CARRIER <34A2>

In AT command mode, error cause display (does not belong to the AT command stand­ard) can be turned on by issuing the command ATW1. The shown error causes use the 
coding defined by the CAPI definition. ISDN error causes from the ISDN network are 
always coded as 34xxH, where xx represents the hexadecimal version of the ISDN error 
cause (see page 84). All other causes are CAPI error causes (see page 91).

4.3 Serial status lines

The behaviour of the output serial status lines DSR, CTS, DCD, RI and the input serial 
status lines DTR, RTS can be configured with AT and configurator commands

After power on all serial status lines from the TA will be inactive.
The serial status line DSR can be configured to signal the activation of the current com­mand set (cdsr=0). When changing the command set (cmds) the DSR line goes off during 
this change phase.
The serial input status lines DTR and RTS will be controlled of an interrupt in the IDW­90 firmware. With regard of this behave the maximum input level change must be lower 
than 1kHz.

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