TCP/IP Command Set - Falcom: Startseite · TANGO55I & TANGO56 TCP/IP COMMAND SET VERSION 1.00 1 USERS INTERFACE Both modems represent over TCP/IP stack a kind of serial communication.

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TCP/IP Command Set for TANGO55i/56i modems

Description

Version 1.00, 17/06/2005

TANGO55I & TANGO56 TCP/IP COMMAND SET VERSION 1.00

Index of contents

0 OVERVIEW...............................................................................4

0.1 RELATED DOCUMENTS ..............................................................................................................5 0.2 USED ABBREVIATIONS ...............................................................................................................5

1 USERS INTERFACE....................................................................6

2 GET STARTED............................................................................9

2.1 MODEM CONFIGURATION .......................................................................................................9 2.2 ISP, GPRS CONFIGURATION CONFIGURATION PARAMETERS OF GERMAN SERVICE PROVIDER ..... 17 2.3 SETUP SERIAL APPLICATIONS OVER TCP/IP.............................................................................. 18 2.4 AUTOMATIC START BY USING IP+AUTO=1 COMMAND............................................................ 18 2.5 TROUBLESHOOTING............................................................................................................... 19

This confidential document is a property of FALCOM GmbH and may not be copied or circulated without previous permission.

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Version history:

Version number Author Changes

1.00 Fadil Beqiri - Initial version


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Cautions Information furnished herein by FALCOM are accurate and reliable. However, no responsibility is assumed for its use. Please, read carefully the safety precautions. If you have any technical questions regarding this document or the product described in it, please contact your vendor. General information about FALCOM and its range of products are available at the following Internet address: http://www.falcom.de/

Trademarks Some mentioned products are registered trademarks of their respective companies.

Copyright This manual is copyrighted by FALCOM GmbH with all rights reserved. No part of this manual may be produced in any form without the prior written permission of FALCOM GmbH.

FALCOM GmbH. No patent liability is assumed with respect to the use of the information contained herein.


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http://www.falcom.de/


0 OVERVIEW This manual is focussed on the GSM and GPRS data solutions of the TANGO55i/56i using TCP/IP and PPP stack. TANGO55i/56i are GSM modems which contain the TCP/IP and PPP internet capable protocols. Internet applications for an embedded devices can be performed over a GPRS network. A possible application scenario for such devices would be e.g. that maintenance and configuration of many embedded devices is managed from the central system over the internet. The advantage of these modem is that the existing infrastructure is not required to be changed, instead additional functionalities can be extended. Another advantage of the modem is that it is GPRS capable i.e. it can 24 h on the day be on-line without additional costs.

The figure below shows a simply architecture of the TANGO55i/56i using TCP/IP stack functionality.

Figure 1: Simply architecture of the TANGO55i/56i using TCP/IP stack

The integration of TCP/IP stack into the equipment converts it to a stand-alone client that can be connected to the internet through any GSM 850/1800/1850 network (TANGO56i ) or any GSM 950/1800/1850 network (TANGO55i). Both modems can send and receive data by GSM/GPRS network using TCP/IP stack. they support SMS and fax calls. The TANGO55i/56i TCP/IP modems can be easily controlled by using AT or IP commands. Available in tri band configurations, this full type approved integrated modem constitutes a self contained, fully integrated implementation of the GSM/GPRS. TANGO55i/56i TCP/IP modems support GPRS class B, class 10 (making download at speeds up to 85 kbps). For further details regarding technical details refer to the related dokuments [1].


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0.1 Related documents

[1] TANGO55i/56i_user_manual.pdf [2] TANGO55/56 at_command_set.pdf

0.2 Used abbreviations

Abbreviation Description

GPRS General Packet Radio Service

GSM Global Standard for Mobile Communications

TCP Transmission Control Protocol

IP Internet Protocol

MT Mobile Terminal

TE Terminal Equipment

GGSN Gateway GPRS Support Node

GMM/SM GPRS Mobility Management/Session Management

SMS Short Message Service

PDP Packet Data Protocol

APN Access Point Name

DTE Data Terminal Equipment

DCE Data Communications Equipment

SDU Service Data Unit

WWW World Wide Web


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1 USERS INTERFACE Both modems represent over TCP/IP stack a kind of serial communication. Please note that, the description in chapters below is applied for both TANGO55i and TANGO56i. TCP is the most widely used transport protocol for non-realtime Internet applications like WWW, file Transfer. It provides a connection-oriented end-to-end service ensuring the reliable transfer of data. As with all other communications protocol, TCP/IP is composed of layers:

IP - is responsible for moving packet of data from node to node. IP forwards each packet based on a four byte destination address (the IP number). IP operates on gateway machines that move data from department to organization to region and then around the world.

TCP - is responsible for verifying the correct delivery of data from client to server. Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received.

PORT - is a name given to the package of subroutines that provide access to TCP/IP on most system.

The architecture of protocol stack is shown in the figure below.

Figure 2: Architecture of TANGO55i/56i TCP/IP stack.

The applications for Internet services such as the SMTP client, DNS, HTTP and FTP available in the figure above are already not functional (not implemented in the TCP-IP stack).


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The modem offers two kind of modes on the serial interface, the COMMAND and the DATA mode. Both modes are activated by software. In the DATA mode the serial communication between Modem and Server is applied over TCP/IP stack. For example, sending IP commands (ip+gprs=1 and ip+conn) enable the modem to perform a TCP connection to the server. So the Data which are sent to the serial port of the modem will be transmited via TCP connection to the remote server and vice versa. In the COMMAND mode the user can send commands/instructions to configure or to perform the specific events in the TANGO55i modem. The following commands representing the functionalities of modem:

Commands Description ip+help shows all IP commands ip+bridg Sets the target modem into the AT command mode (bridg mode). ip+abaud Reads the current baud rate communication between GSM and TCP/IP-modem

ports ip+debug activates/deactivates the Debug information ip+v knowledge about present GPRS configuration ip+ref reloads the factory settings ip+echo enable/disable command echo. Echo mode off/on ip+baud sets or queries the DTE-DCE interface bit rate ip+cpin enter PIN ip+gprs starts/stops/status of GPRS PDP context attached or detached ip+apn queries APN ip+reqq requests the selected Quality of Service ip+minq specifies/requests the Minimum a Quality of Service ip+call enters/requests the dialing number of Provider ip+user enters/requests user name and Password ip+saddr enters/requests IP address and Socket number of Servers ip+conn establishes a TCP connection to the Server ip+reset restarts the modem ip+w saves the current configuration of the modem ip+auto sets the start-up mode of the GPRS and TCP/IP connection ip+time sets the global time out of the modem

All of these commands are either for implementing, displaying or entering new parameters. The write commands and supported values are separated by equal sing “=”, which has to be entered directly after the command without space sings, e.g. ip+user=user1,pwd001 (enter the user name and password) or ip+gprs=1 (GPRS attach). In addition the modem support some AT commands for modem connection (X.25), too. So it is possible to use additional functions of GSM modem. In order to use this feature, the command ip+bridg=1 has to be sent from the user-side to the target modem via serial interface. Once the target modem responds OK, except the AT-Commands listed in table below all other command can be sent to the modem. By pressing the “ESC” key (decimal #27) the modem will be set back into the COMMAND mode. The AT commands listed in table below are not allowed, because they can change the modem status, so that the modem can be set up into an unstable condition. The following AT commands are not allowed:

Commands DESCRIPTION AT&C Set circuit Data Carrier Detect (DCD) function mode AT&D Set circuit Data Terminal Ready (DTR) function mode AT&F Set all current parameters to manufacturer defaults


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AT&S Set circuit Data Set Ready (DSR) function mode AT&V Display current configuration AT&W Store current configuration to user defined profile ATA Answer a call ATD Mobile original call to dial a number ATE Enable command echo ATH Disconnect existing connection ATO Switch from command mode to data mode/PHP online mode ATQ Set result code presentation mode ATV Set result code format mode ATZ Set all current parameters to user defined profile AT+IPR Set fixed local rate AT+CFUN Set phone functionality


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2 GET STARTED This chapter provides a reference of IP commands and responses, which allow the host application to easily access the Internet. To transmit data via GPRS and Internet, the application software uses a TCP/IP and a PPP stack, which enables manually performing of the TCP connections. However, application for TCP connections can be established by executing a series of IP commands. Of course, you may also manually type these commands using any terminal program. To set-up the hardware, please refer to the hardware description chapter 8. To update a new TCP/IP firmware onto the TANGO55i modem, please, refer to the chapter Fehler! Verweisquelle konnte nicht gefunden werden. in this document. Once the connection of the TANGO55i modem to PC host is made, just type ip+help and enter key; a number of the supported commands are received. Based on the these commands the TANGO55i modem can be configured and a wide of TCP applications can be implemented. The read commands can be set to the target modem and proper responses are returned, if the read parameter(s) corresponding to the command is/are already available, else the traget device responds ERROR (no value found). If the connected TANGO55i modem do not response when you send a command, please refer to the chapter 2.5. Sending of commands to the target modem, throughout the documentation is used <enter>, which signifies the ENTER key and it is not normally printed (for this reason they are customarily shown enclosed in brackets). The commands supported by the TANGO55i modem are describe in the following chapter.

2.1 Modem Configuration

COMMANDS DESCRIPTION Basis commands

Read command IP+HELP

Displays the list of all usable IP commands. Example

Enter: IP+HELP Response: (List of supported IP commands)

Excute command IP+BRIDG=<n>

This command enables sending of AT commands direct to the target modem. In this case it can be used as a normal GSM/GPRS modem. See description of this command. Parameter description: <n> possible values: 1 Set the TANGO55i into the AT command mode Examples

Enter: IP+BRIDG=1 Response: OK/ERROR

The target modem responds OK, if the TANGO55i modem is set into the AT command mode, otherwise the traget modem responds ERROR (the entered value is incorrectly typed, or the target device is already set into the Data mode).

Write command IP+DEBUG=<n>

This command activates/deactivates the debug information. It enables a special debugging mode that displays the data being sent to the GSM/GPRS engine and responses received. The integrated debugger can help you to track down the initialization/execution of firmware, to monitor the specified values and settings and runtime errors etc. Parameter description: <n> possible values: 0 Debug off 1 Debug on


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Examples Enter: IP+DEBUG=0 Response: OK/ERROR Enter: IP+DEBUG=1 Response: OK/ERROR

Read command IP+DEBUG

This command returns the current status of debug. Example

Enter: IP+DEBUG Response: Debug off/on OK/ERROR

Read command IP+V

This read command returns the current parameter of GPRS settings. The configuration depending on whether or not PIN authentication has been done. Example:

Enter: IP+V<enter> Response: see write commands (APN, REQQ, MINQ etc.)

Execute command IP+REF

This command loads the factory settings. The factory settings are listed below:

ECHO =1 SIMPIN =1111 APN =internet.t-d1.de REQQ =1,3,4,3,0,0 MINQ =1,0,0,0,0,0 CALL =*99***1# USERNAME =t-d1 PASSWORD =falx BAUD =57600 SADDR =132.151.6.21,80

Example: Enter: IP+REF<enter> Response: OK/ERROR

Write command IP+ECHO=<n>

This setting determines whether or not the TA echoes characters received from TE during command state. Parameter description:

<n> possible values: 0 echo off 1 echo on Example:

Enter: IP+ECHO=0<enter> //echoes characters are switched off Response: OK/ERROR

Write command IP+RESET

The write command can be used to reset the modem. Example:

Enter: IP+RESET<enter> Response: OK/ERROR

Read command IP+ABAUD

This command reads the current bit rate communication of GSM port (ASC0) to integrated i-modem. If “ERROR” is returned, there is no communication established, maybe the GSM engine is turned off or both ports are not connected properly. Example:

Enter: IP+ABAUD<enter> Response: OK/ERROR

Write command IP+BAUD=<value>

This command specifies the DCE bit rate. When you set a fix rate, make sure that both DTE (via terminal program which currently use) and DCE are configured to the same rate. The setting stored in the non-volatile memory will be used whenever the engine is powered up again. Parameter description:

< <value> possible values: 1200


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... 115200

Example: Enter: IP+BAUD=115200<enter> Response: OK/ERROR

Read command IP+BAUD

This command reads the current DTE-DCE bit rate communication. The setting stored in the non-volatile memory will be shown on the display of terminal program. Example:

Enter: IP+BAUD<enter> Response: 115200

Write command IP+CPIN=<pin>

The write command lets the modem store the entered PIN and allows the modem to register to the GSM network. Successful PIN authentication only confirms that the entered PIN was recognized and correct. The PIN acception does not necessarily imply that the TANGO55i is registered to the desired network. Typical example: PIN was entered and accepted, but the TANGO55i fails to register to the network. This may be due to missing network coverage, denied network access with currently used SIM card, no valid roaming agreement between home network and currently available operators etc. Example:

Enter: IP+CPIN=1111<enter> Response: OK/READY/ERROR

After three failures to enter PIN, the SIM card is blocked. ERROR will prompt the client to unblock the SIM card by entering the associated PUK (= PIN Unblocking Key/Personal Unblocking Key). After ten failed attempts to enter the PUK, the SIM card will be invalidated and no longer operable. In such a case, the card needs to be replaced. PIN consists of 4 to 8 digits, PUK is an 8-digit code only. To unblock a disabled PIN you have to set the TANGO55i into the AT command mode by using the IP+BRIDG=1. After the TANGO55i modem responds OK, enter the AT command AT+CPIN=<PUK>,<PIN>. For more details about this command refer to the “I56_TANGO55i_AT_Command_Set” manual.

Execute command IP+W

The TANGO55i modem stores the current set parameters to a user-defined profile in the on board FLASH memory. This configuration will be used after each power up of the TANGO55i modem, and as long as no new configuration is performed. Example:

Enter: IP+W<enter> Response: OK/ERROR

Write command IP+AUTO=<n>

This command specifies the start-up mode of GPRS and TCP/IP connection. Parameter description: <n> possible values: 0 auto off (manual start-up connection) 1 auto on (auto start connection) Example:

Enter: IP+AUTO=1<enter> Response: OK/ERROR

If the value of this command is set to 1, the TANGO55i modem will start up automatically to perform a GPRS and TCP/IP connection, after the settings are saved (by using IP+W) and after restarting the TANGO55i modem. See also chapter 2.4 for more details.

Read command IP+AUTO

This read command returns the current start-up mode of the GPRS and TCP/IP connection specified with the write command IP+AUTO=<n>. Example:

Enter: IP+AUTO<enter> Response: AUTO ON/OFF OK/ERROR

Write command IP+TIME=<n>

It specifies the global timeout (in milliseconds) for the modem. The default value is set to 1 msec. Parameter description: <n>=1..9 //unit is msec Example:

Enter: IP+TIME=1<enter> Response: OK/ERROR Parameter: 1-9

Read command Indicates the current set timeout value in milliseconds.


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IP+TIME

Example: Enter: IP+TIME<enter> Response: TIMEOUT:<current timeout> OK/ERROR

GPRS commands Write command IP+APN=<apn>

This command specifies the APN Access Point Name (text string). The APN is logical name that is used to select the GGSN or the external packet data network. In other word, the name of access point that connects the modem to the Internet. If the value is null or omitted, then the subscription value will be requested. The APN name that your network operator has provided you. Example:

Enter: AT+IPN= volume.d2gprs.de //for D2 operator Response: OK/ERROR

Write command IP+REQQ=<value>

This command allows the TE to specify a Quality of Service Profile that is used when the MT sends an Activate PDP Context Request message to the network. The write command specifies a profile for the context identified by the (local) context identification parameter, <cid> included in the <value> parameter. Parameters description: <value>=[<cid>[,<precedence>,<delay>[,<reliability>[,<peak>[,<mean>]]]]]]

<cid> (numeric) Parameter specifies a particular PDP context definition. The parameter is local to the TE-MT interface and is used in other PDP context-related commands. 1 ... 2.

<precedence> Precedence class (numeric) [0] network subscribed value 1 High Priority Service commitments shall be maintained ahead of precedence classes 2 and 3 2 Normal priority Service commitments shall be maintained ahead of precedence class 3 3 Low priority

Service commitments shall be maintained <delay> Delay class (numeric)

The Delay parameter defines the end-to-end transfer delay incurred in the transmission of SDUs through the GPRS network(s). [0] network subscribed value

SDU size: 128 octets: Delay Class Mean Transfer Delay 95 percentile Delay 1 (Predictive) <0.5 <1.5 2 (Predictive) <5 <25 3 (Predictive) <50 <250 4 (Best Effort) Unspecified

SDU size:1024 octets: Delay Class Mean Transfer Delay 95 percentile Delay 1 (Predictive) <0.5 <1.5 2 (Predictive) <5 <25 3 (Predictive) <50 <250 4 (Best Effort) Unspecified

<reliability> Reliability class (numeric) [0] network subscribed value 1 Non real-time traffic, error-sensitive application that cannot cope with data loss 2 Non real-time traffic, error-sensitive application that can cope with infrequent data loss 3 Non real-time traffic, error-sensitive application that can cope with data loss, GMM/SM, and SMS 4 Real-time traffic, error-sensitive application that can cope with data loss


5 Real-time traffic, error non-sensitive application that can cope with data loss<peak> Peak throughput class (numeric)

[0] network subscribed value Peak Throughput Class Peak Throughput (in octets per second) 1 Up to 1 000 (8 kbit/s). 2 Up to 2 000 (16 kbit/s). 3 Up to 4 000 (32 kbit/s). 4 Up to 8 000 (64 kbit/s). 5 Up to 16 000 (128 kbit/s). 6 Up to 32 000 (256 kbit/s). 7 Up to 64 000 (512 kbit/s). 8 Up to 128 000 (1 024 kbit/s). 9 Up to 256 000 (2 048 kbit/s).

<mean> numeric parameter for the mean throughput class [0] network subscribed value

Mean Throughput Class Mean Throughput (in octets per hour) 1 100 (~0.22 bit/s) 2 200 (~0.44 bit/s) 3 500 (~1.11 bit/s) 4 1 000 (~2.2 bit/s) 5 2 000 (~4.4 bit/s) 6 5 000 (~11.1 bit/s) 7 10 000 (~22 bit/s) 8 20 000 (~44 bit/s) 9 50 000 (~111 bit/s) 10 100 000 (~0.22 kbit/s) 11 200 000 (~0.44 kbit/s) 12 500 000 (~1.11 kbit/s) 13 1 000 000 (~2.2 kbit/s) 14 2 000 000 (~4.4 kbit/s) 15 5 000 000 (~11.1 kbit/s) 16 10 000 000 (~22 kbit/s) 17 20 000 000 (~44 kbit/s) 18 50 000 000 (~111 kbit/s) 31 best effort.

Example: Enter: IP+REQQ=1,3,4,3,7,31<enter> Response: OK/ERROR

Read command IP+REQQ

The read command returns the current settings for each defined context. If no requested profile was explicitly specified for a context, simply OK will be returned, but default values will be used for that context. Example:

Enter: IP+REQQ<enter> //read command Response:+CGQREQ:<PDP_type>, (list of supported <precedence>s), (list of supported <delay>s), (list of supported <reliability>s), (list of supported <peak>s), (list of supported <mean>s) [<CR><LF>+CGQREQ:...] OK/ERROR

Parameters description: <PDP_type> String parameter of Packet Data Protocol type IP <precedence> See write command <delay> See write command <reliability> See write command <peak> See write command <mean> See write command

Write command This command allows the TE to specify a minimum acceptable profile which is checked by the


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IP+MINQ=<value>

MT against the negotiated profile returned in the Activate PDP Context Accept message. The write command specifies a minimum acceptable profile for the context identified by the (local) context identification parameter, <cid> included in the <value> parameter. Parameters description: <value>:[<cid>[,<precedence>[,<delay>[,<reliability>[,<peak>[,<mean>] ]]]]]

<cid> (numeric) Parameter specifies a particular PDP context definition. The parameter is local to the TE-MT interface and is used in other PDP context-related commands. 1 ... 2

<precedence> Precedence class (numeric) [0] network subscribed value 1 High Priority Service commitments shall be maintained ahead of precedence classes 2 and 3 2 Normal Priority Service commitments shall be maintained ahead of precedence class 3 3 Low Priority Service commitments shall be maintained

<delay> Delay class (numeric) The Delay parameter defines end-to-end transfer delay incurred in the transmission of SDUs through GPRS network(s).

[0] network subscribed value SDU size:128 octets:

Delay Class Mean Transfer Delay 95 percentile Delay 1 (Predictive) <0.5 <1.5 2 (Predictive) <5 <25 3 (Predictive) <50 <250 4 (Best Effort) Unspecified

SDU size: 1024 octets: Delay Class Mean Transfer Delay 95 percentile Delay 1 (Predictive) <0.5 <1.5 2 (Predictive) <5 <25 3 (Predictive) <50 <250 4 (Best Effort) Unspecified

<reliability> Reliability class (numeric) [0] network subscribed value 1 Non real-time traffic, error-sensitive application that cannot cope with data loss 2 Non real-time traffic, error-sensitive application that can cope with infrequent data loss 3 Non real-time traffic, error-sensitive application that can cope with data loss, GMM/SM, and SMS 4 Real-time traffic, error-sensitive application that can cope with data loss 5 Real-time traffic, error non-sensitive application that can cope with data loss

<peak> (numeric) Peak throughput class (in octets per second) [0] network subscribed value

Peak Throughput Class

Peak Throughput (in octets per second)

1 Up to 1 000 (8 kbit/s). 2 Up to 2 000 (16 kbit/s). 3 Up to 4 000 (32 kbit/s). 4 Up to 8 000 (64 kbit/s). 5 Up to 16 000 (128 kbit/s). 6 Up to 32 000 (256 kbit/s). 7 Up to 64 000 (512 kbit/s). 8 Up to 128 000 (1 024 kbit/s).


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9 Up to 256 000 (2 048 kbit/s). <mean> (numeric)

Mean throughput class [0] network subscribed value

Mean Throughput Class Mean Throughput (in octets per hour) 1 100 (~0.22 bit/s) 2 200 (~0.44 bit/s) 3 500 (~1.11 bit/s) 4 1 000 (~2.2 bit/s) 5 2 000 (~4.4 bit/s) 6 5 000 (~11.1 bit/s) 7 10 000 (~22 bit/s) 8 20 000 (~44 bit/s) 9 50 000 (~111 bit/s) 10 100 000 (~0.22 kbit/s) 11 200 000 (~0.44 kbit/s) 12 500 000 (~1.11 kbit/s) 13 1 000 000 (~2.2 kbit/s) 14 2 000 000 (~4.4 kbit/s) 15 5 000 000 (~11.1 kbit/s) 16 10 000 000 (~22 kbit/s) 17 20 000 000 (~44 kbit/s) 18 50 000 000 (~111 kbit/s) 31 best effort.

Example: Enter: IP+ MINQ=1,0,0,0,0,0,0<enter> Response: OK/ERROR

Read command IP+MINQ

The read command returns the current settings for each defined context. If no minimum profile was explicitly specified for a context, simply OK will be returned, but default values will be used for that context. Example:

Enter: IP+MINQ<enter> //read command Response: <PDP_type>, (list of supported <precedence>s), list of supported <delay>s), (list of supported <reliability>s), (list of supported <peak>s), (list of supported <mean>s) [<CR><LF>+CGQREQ: ...] OK/ERROR

Parameters description: <PDP_type> String parameter of Packet Data Protocol type IP <precedence> See write command <delay> See write command <reliability> See write command <peak> See write command <mean> See write command

Write command IP+CALL=<value>

This command causes the MT to perform whatever actions are necessary to establish communication between the TE and the external PDN. The V.25ter command causes the MT to enter the V.25ter online data state and, with the TE, to start the specified layer 2 protocol. If the context to be used is already activated, it will be deactivated first. This ensures that the right context parameters will be used (e.g. QoS changes since the last context activation or the called address specified by IP+CALL). Example of how to use this command can be seen below. Example:

Enter: IP+CALL=*99***1# Response: CONNECT/ NO CARRIER

To confirm acceptance of the command to entering the V.25ter online data state the TANGO55i responds CONNECT, otherwise when the Layer 2 protocol has terminated, either as a result of an orderly shut down of the PDP or an error, the MT enters V.25ter command state and returns


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NO CARRIER. Write command IP+USER=<user>,<psw>

This command enters the user name and password that your network operator has provided you. The password, user name or ID allow you to log on your modem to the external data network. Contact your network provider in order to obtain the requested information. Example:

Enter: IP+USER=user,psw<enter> Response: OK/ERROR

Read command IP+USER

The read command returns the current settings for each defined user name and password. If no settings were specified, simply OK will be returned. Example:

Enter: IP+USER<enter> Response: <displays text strings or digits> OK/ERROR

Write command IP+GPRS=<value>

The write command enables you to activate or deactivate the specified PDP context. After the command has been completed, the TANGO55i modem remains in V.25ter command state. Parameter description: <value> possible values: 0 GPRS detach 1 GPRS attach Examples:

Enter: IP+GPRS=1<enter> Response: OK/ERROR Enter: IP+GPRS=0<enter> Response: OK/ERROR

If the TANGO55i modem is already in the requested state, the command is ignored and the OK response is returned. Any active PDP contexts will be automatically deactivated when the attachment state changes to detached. If the TANGO55i modem is not able to attach for more than 5 minutes, the command returns ERROR, though the TANGO55i modem is still trying to attach. If the TANGO55i modem is not able to detach for more than 1 minute, command returns ERROR, but the TANGO55i modem is still trying to detach. If an attach is issued during a running detach, command returns ERROR, unspecified GPRS error. If the TANGO55i modem is in dedicated mode, command returns ERROR: operation temporary not allowed.

Read command IP+GPRS

The read command enables the TANGO55i modem to request the current state of modem, means attached to or detached from the GPRS service. After the request command has been completed, the TANGO55i modem returns actual state of modem. Examples:

Enter: IP+GPRS<enter> Response: 0 or 1 //see write command

OK/ERROR Execute command +++

This command is only available during a TCP/IP connection. The +++ character sequence causes the TA to cancel the TCP connection and switch it back into the command mode, but the GPRS is still attached to the network. This mode allows you to enter the IP commands to the modem, but is not possible to use AT commands.

Commands for TCP/IP connection Write command IP+SADDR=<ip>,<port>

This command serves to set up the necessary parameters the IP address and port number (socked) that your modem uses when communicating with the external network (remote server). The specified settings are temporarily stored in the SRAM when the TCP connection is already established (using the IP+CONN). <ip>

To exchange data over TCP, the TANGO55i modem must know the address of the remote server. The IP address consists of 32 bits, each field above consists of up to three decimal numbers from 0 to 255. The entered IP address is responsible for moving packet of data from node to node. Entries of the IP addresses have the following format: XXX.XXX.XXX.XXX

<port> The port number is used for communication between the TANGO55i modem and remote server. The port number is a special memory location that exists when the TANGO55i modem and the remote server are in communication via TCP/IP. It is a name given to the package of subroutines that provide access to TCP/IP on most system.

If one of the specified values is invalid, or the parameter field is blank and it is required, the authentication to the remote server failed. If you do not know the correct settings of the romote server, contact your network administrator.


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Example: Enter: IP+SADDR=132.151.6.21,80<enter> Response: OK/ERROR

Read command IP+SADDR

This read command serves to request the current settings of the IP address and port number (socked) that your modem uses to communicate with the remote server. Example:

Enter: IP+SADDR<enter> Response: <displays the IP and PORT number>

OK/ERROR The target modem responds OK, if the parameters value corresponding to the command are already available, else the traget modem responds ERROR (no value available).

Write/Execute command IP+CONN=<ip>,<port>

This write/execute command serves to set up the necessary parameters such as the IP address and port number for a TCP connection. Using this setting the target modem starts automatically to establish a TCP connection to the remote server using the <ip> and <port>. In this case the execute command IP+CONN is not required to be entered. The specified settings are temporarily stored in the SRAM after that the TCP connection is established. <ip>

To exchange data over TCP, the TANGO55i modem must know the address of the remote server. The IP address consists of 32 bits, each field above consists of up to three decimal numbers from 0 to 255. The entered IP address is responsible for moving packet of data from node to node. Entries of the IP addresses have the following format: XXX.XXX.XXX.XXX

<port> The port number is used for communication between the TANGO55i modem and remote server. The port number is a special memory location that exists when the TANGO55i modem and the remote server are in communication via TCP/IP. It is a name given to the package of subroutines that provide access to TCP/IP on most system.

If one of the specified values is invalid, or the parameter field is blank and it is required, the authentication to the remote server failed. If you do not know the correct settings of the romote server, contact your network administrator. Examples:

Enter: IP+CONN=132.151.6.21,80<enter> Response: OK/ERROR

The target modem responds OK, if the TCP connection to the remote server (the IP address and Port number) is succesfully established, otherwise the traget modem responds ERROR (the IP address and Port number are not available, or the remote server is not operational or while trying to setup the TCP connection errors are occured).

Execute command IP+CONN

This execute command establishes a TCP connection to the specified IP address and port number. Examples:

Enter: IP+CONN<enter> Response: OK/ERROR

The target modem responds OK, if the TCP connection to the remote server (the IP address and Port number) is succesfully established, otherwise the traget modem responds ERROR (the IP address and Port number are not available, or the remote server is not operational or while trying to setup the TCP connection errors are occured).

2.2 ISP, GPRS configuration configuration parameters of German service provider

The following table presents GPRS parameters of selected German service providers and operators:

T-D1 Vodafon D2 E-Plus Genion O2 APN REQoS MIQoS USERNAME PASSWORD

internet.t-d1.de 1,3,4,3,0,0 1,0,0,0,0,0 (optional) (optional)

volume.d2gprs.de 1,3,4,3,7,31 1,0,0,0,0,0 ""(None) ""(None)

internet.eplus.de 1,2,4,3,9,31 1,0,0,0,0,0 "eplus" ""(None)

APN=internet REQoS=1,2,4,3,9,31 MIQoS=1,0,0,0,0,0 USERNAME=""(None) PASSWORD=""(None)


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Table 1: Service provider information, valid 16.10.2001

2.3 Setup serial applications over TCP/IP

In order to setup properly a serial application over TCP/IP the following essential prerequisites settings must be entered:

1. To allow sending of AT commands to the target modem, set the device into the AT-command mode by using the ip+bridg=1 command. Send all AT commands required for your application. Finally, press “ESC” key to set the target modem back into the IP command mode. Pass this step if no configuration is required.

2. Enter the GPRS settings from your network provider (see table below, the GPRS configuration settings differ depending on the SIM card used).

3. Attach the TANGO55I to the GPRS network. 4. Enter the IP-address and PORT-number of the remote server (see table

below, the IP-address and Port-number differ depending on the remote server used).

5. Store all current settings by using IP+W command. 6. Perform a TCP connection to the remote server.

The example below describes the TD-2 GPRS configuration: Enter command Command description

IP+APN=volume.d2gprs.de<enter> the APN of Provider IP+REGQ=1,3,4,3,7,31<enter> the maximal Quality of Service profile IP+MINQ=1,0,0,0,0,0<enter> the minimum Quality of Service profile IP+CALL=*99***1#<enter> dial number of Provider IP+USER=user,password<enter> Enter the User name and Password (if required) IP+GPRS=1<enter> GPRS attach

IP+SADDR=132.151.6.21,80<enter> Specifies the IP-address and Port-number of Server (IP=132.151.6.21 port=80)

IP+W<enter> Stores all specified settings. IP+CONN<enter> establish a TCP connection

After the TCP connection is established, the modem set itself in the DATA mode. All application data are divided into the TCP packets before transmissions. Correctly received packets are unpacked and transmitted to the serial port. To terminate the current TCP connection the command “+++”<enter> has to be sent to the TANGO55i. When TCP connection is terminated the modem enters automatically into the command mode.

2.4 Automatic start by using IP+AUTO=1 command

Starting the GPRS and TCP application of modem into the auto mode depends on the pre-defined TCP/IP configuration. In order to use properly this functionality of modem, please follow the instructions listed below:

• Send all parameters, which are required for a GPRS attachment of the modem.

• Enter all parameters, which are required to perform a TCP connection, such as IP-address and Port of the remote server, to which the target modem has to be conneted and sends its data.


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• Define the start up mode of connection by entering the command IP+AUTO=1 (auto start connection).

• Store all current settings by using IP+W command. • Finally, restart the target modem to load the new configuration settings.

NOTE: If the IP+W command is not sent to the target modem after the complete configuration is performed (see chapters 2.3 and 2.4), the user specified settings are temporarily stored in the SRAM memory. That means you have to specify the settings for a TCP connection after each power up of the target modem. Once the IP+W command is sent to the target modem the specified setting will be stored into the on board FLASH memory and available after each power up of the TANGO55i modem.

2.5 Troubleshooting

1. The device does not seem to make any GPRS connection. How do I make it? Check if the antenna is properly connected. Check the signal strength of GSM (using AT+CSQ?), see [1] for more

detailed information. Check the communication settings of host device:

The settings are: (57600 Baud rate, 8 Data bit, NO Parity bit, 1 Stop bit, NO Flow control).

Check the GPRS configuration. Turn the modem off and on again.

2. The device is already GPRS attached, but it does not seem to make any TCP connection. How do I perform it? Check if the user specified IP address and Port number of the remote

server are valid. Contact your network administrator to specify the correct IP address and port number.

Check, if the remote server is operational. Turn the modem off and on again. Enter the IP+CONN command to setup a TCP connection.

3. The device responses ERROR when I send a read command to the target modem. The read commands can be set to the target modem and a proper

response can be received, if the value(s) corresponding to the command is/are already available, otherwise the traget device responds ERROR (no value(s) available)


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TCP/IP Command Set - Falcom: Startseite · TANGO55I & TANGO56 TCP/IP COMMAND SET VERSION 1.00 1 USERS INTERFACE Both modems represent over TCP/IP stack a kind of serial communication.

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