ETSI ETS 300 585 ed.3 (1996-09)

Digital cellular telecommunications system (Phase 2) (GSM); Use of Data Terminal Equipment - Data Circuit terminating Equipment (DTE - DCE) interface for Short Message Service (SMS) and Cell Broadcast Service (CBS) (GSM 07.05)

RE/SMG-040705PR3

Digitalni celični telekomunikacijski sistem (faza 2) – Uporaba vmesnika za podatkovno terminalsko opremo –opremo za zaključevanje podatkovnih vodov (DTE-DCE) za storitev kratkih sporočil (SMS) in storitev celične radiodifuzije (GSM 07.05)

General Information

• Status: Published
• Publication Date: 16-Sep-1996
• Technical Committee: SMG 4 - Data Services
• Current Stage: 12 - Completion
• Due Date: 13-Sep-1996
• Completion Date: 17-Sep-1996
• Ref Project: SIST ETS 300 585 E3:2003 - Digital cellular telecommunications system (Phase 2) (GSM); Use of Data Terminal Equipment - Data Circuit terminating Equipment (DTE - DCE) interface for Short Message Service (SMS) and Cell Broadcast Service (CBS) (GSM 07.05)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 585 E3:2003
01-december-2003
'LJLWDOQLFHOLþQLWHOHNRPXQLNDFLMVNLVLVWHPID]D±8SRUDEDYPHVQLND]D
SRGDWNRYQRWHUPLQDOVNRRSUHPR±RSUHPR]D]DNOMXþHYDQMHSRGDWNRYQLKYRGRY
'7('&(]DVWRULWHYNUDWNLKVSRURþLO606LQVWRULWHYFHOLþQHUDGLRGLIX]LMH*60

Digital cellular telecommunications system (Phase 2) (GSM); Use of Data Terminal
Equipment - Data Circuit terminating Equipment (DTE - DCE) interface for Short
Message Service (SMS) and Cell Broadcast Service (CBS) (GSM 07.05)
Ta slovenski standard je istoveten z: ETS 300 585 Edition 3
ICS:
33.070.50 Globalni sistem za mobilno Global System for Mobile
telekomunikacijo (GSM) Communication (GSM)
SIST ETS 300 585 E3:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 585 E3:2003

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SIST ETS 300 585 E3:2003
EUROPEAN ETS 300 585
TELECOMMUNICATION September 1996
STANDARD Third Edition
Source: ETSI TC-SMG Reference: RE/SMG-040705PR3
ICS: 33.060.50
Key words: Digital cellular telecommunications system, Global System for Mobile communications (GSM)
R
GLOBAL SYSTEM FOR
MOBILE COMMUNICATIONS
Digital cellular telecommunications system (Phase 2);
Use of Data Terminal Equipment - Data Circuit terminating
Equipment (DTE - DCE) interface for
Short Message Service (SMS) and Cell Broadcast Service (CBS)
(GSM 07.05)
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
Tel.: [phone] - Fax: [phone]
Copyright Notification:
No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1996. All rights reserved.

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
Contents
Foreword .7
0 Scope.9
0.1 Normative references.10
0.2 Abbreviations .10
1 Reference configuration .11
1.1 V.24 Interface Circuits .11
1.1.1 Circuit definitions for the SMS Block mode.11
1.1.2 Circuit definitions for the SMS Text and PDU modes.12
2 SMS Block Mode.13
2.1 Beginning and ending of SMS/CBS Block Mode.13
2.1.1 Beginning SMS/CBS Block Mode.13
2.1.2 Returning from SMS/CBS Block Mode To Default Mode.13
2.2 Protocol description.14
2.3 Requesting messages already held in the Mobile Termination .15
2.3.1 Requesting List Of Messages.15
2.3.2 Requesting Transfer Of Messages.15
2.3.2.1 Requesting Transfer Of A Specific Message.15
2.3.2.2 Requesting Transfer Of All Messages .16
2.3.3 Requesting Diversion Of Incoming Messages.16
2.3.3.1 Requesting SMS Messages.16
2.3.3.2 Requesting CBS Messages .17
2.3.3.3 Requesting indication of message arrival.17
2.3.4 Requesting Transfer Into Mobile Termination .18
2.3.5 Requesting Deletion Of Messages .18
2.4 Message functional definitions and contents.19
2.4.1 Commands Issued By The Terminal Equipment.19
2.4.1.1 List Request.20
2.4.1.2 Get Message .20
2.4.1.3 Get First Message.20
2.4.1.4 Get Next Message.20
2.4.1.5 Transfer Inc SMS.20
2.4.1.6 Indicate Inc SMS .21
2.4.1.7 Transfer Inc CBS.21
2.4.1.8 Insert SMS.21
2.4.1.9 Delete message.21
2.4.1.10 Unable to process.22
2.4.1.11 End SMS Mode .22
2.4.1.12 Acknowledge Message .22
2.4.2 Responses/Indications Issued By The MT .22
2.4.2.1 Message List.23
2.4.2.2 Message.23
2.4.2.3 Get Message Failure.23
2.4.2.4 Inc Message.24
2.4.2.5 Message Arrived.24
2.4.2.6 Insert SMS Complete.24
2.4.2.7 Insert SMS Failure.24
2.4.2.8 Delete Message Complete .25
2.4.2.9 Delete Message Failure.25
2.4.2.10 Unable To Process.25
2.4.2.11 End SMS Mode .25
2.4.2.12 Request Confirmed .26

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2.5 General message format and information elements coding.26
2.5.1 Message Type .26
2.5.2 Other Information Elements.28
2.5.2.1 Short Message Reference .28
2.5.2.2 SMS Transfer Type.29
2.5.2.3 Indication Type .30
2.5.2.4 Insert Type.31
2.5.2.5 Short Message Index .32
2.5.2.6 Short Message Data .34
2.5.2.7 Cause .36
2.5.2.8 Index Count .37
2.5.2.9 CBS Transfer Type .37
2.5.2.10 Page Index.38
2.5.2.11 Last Short Message.38
2.5.2.12 Confirm Type.39
2.5.2.13 TP-Failure Cause.40
3. Text Mode.41
3.1 Parameter Definitions.41
3.2 General Configuration Commands.44
3.2.1 Select Message Service +CSMS .44
3.2.2 Preferred Message Storage +CPMS.45
3.2.3 Message Format +CMGF .45
3.2.4 Enter SMS Block Mode Protocol +CESP.46
3.2.5 Message Service Failure Result Code +CMS ERROR.46
3.2.6 Informative Examples.47
3.3 Message Configuration Commands.48
3.3.1 Service Centre Address +CSCA .48
3.3.2 Set Text Mode Parameters +CSMP.48
3.3.3 Show Text Mode Parameters +CSDH .49
3.3.4 Select Cell Broadcast Message Types +CSCB.49
3.3.5 Save Settings +CSAS .50
3.3.6 Restore Settings +CRES.51
3.3.7 Informative Examples.51
3.4 Message Receiving and Reading Commands.53
3.4.1 New Message Indications to TE +CNMI .53
3.4.2 List Messages +CMGL .56
3.4.3 Read Message +CMGR.57
3.4.4 Informative Examples.58
3.5 Message Sending and Writing Commands.60
3.5.1 Send Message +CMGS .60
3.5.2 Send Message from Storage +CMSS .61
3.5.3 Write Message to Memory +CMGW .61
3.5.4 Delete Message +CMGD .62
3.5.5 Send Command +CMGC.62
3.5.6 Informative Examples.63
4 PDU Mode .65
4.1 List Messages +CMGL .65
4.1.1 Read Message +CMGR.66
4.1.2 Send Message +CMGS .66
4.1.3 Write Message to Memory +CMGW .67
4.1.4 Send Command +CMGC.68
Annex A (Normative): Character Set Conversions for SMS Text Mode.69

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Annex B (Informative): Example of processing a data block.72
B.1 Example state diagrams for the block receiver.72
B.2 Example of coding and decoding a data block.72
History .76

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
Foreword
This European Telecommunication Standard (ETS) has been produced by the Special Mobile Group
(SMG) Technical Committee (TC) of the European Telecommunications Standards Institute (ETSI).
This ETS defines a protocol for use of the V series DTE/DCE interface over the R reference point for SMS
and CBS procedures within the Digital cellular telecommunications system (Phase 2).
This ETS correspond to GSM 07.05 version 4.6.0.
The specification from which this ETS has been derived was originally based on CEPT documentation,
hence the presentation of this ETS may not be entirely in accordance with the ETSI/PNE rules.
Reference is made within this ETS to GSM Technical Specifications (GSM-TS) (note).
NOTE: TC-SMG has produced documents which give the technical specifications for the
implementation of the Digital cellular telecommunications system. Historically, these
documents have been identified as GSM Technical Specifications (GSM-TSs). These
TSs may have subsequently become I-ETSs (Phase 1), or ETSs (Phase 2), whilst
others may become ETSI Technical Reports (ETRs). GSM-TSs are, for editorial
reasons, still referred to in current GSM ETSs.
Transposition dates
Date of adoption of this ETS: 30 September 1996
Date of latest announcement of this ETS (doa): 31 December 1996
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 30 June 1997
Date of withdrawal of any conflicting National Standard (dow): 30 June 1997

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
0 Scope
This European Telecommunication Standard (ETS) defines three interface protocols for control of SMS
functions within a GSM mobile telephone from a remote terminal via an asynchronous interface.
Section 2 defines a binary protocol (“Block Mode”). The protocol includes error protection and is suitable
for use where the link may not be completely reliable. It will be of particular use where control of remote
devices is required. Efficient transfer of binary encoded user data is possible.
Section 3 defines a character-based interfaced based on “AT” commands (“Text Mode”). This mode is
suitable for unintelligent terminals or terminal emulators, and for application software built on command
structures like those defined in V.25ter. Some of the commands defined in Section 3 will also be useful for
implementations of Section 2 and/or Section 4, for example enabling an indication of incoming SMS
messages.
Section 4 defines a character-based interface with hex-encoded binary transfer of message blocks (“PDU
Mode”). This mode is suitable for software drivers based on AT command structures which do not
understand the content of the message blocks and can only pass them between the MT and “upper level”
software resident in the TE.
In all three modes, the terminal is considered to be in control for SMS/CBS transactions.
This specification considers the mobile termination to be a single entity. Other GSM Technical
Specifications describe the split of functionality between the mobile equipment and SIM.
The three “modes” referred to above, are represented in figure 0.1/GSM 07.05.
The “Block mode” is a self contained mode in its own right, and when entered, control will remain within
that mode until the procedures to exit the mode are executed, after which control is returned to the V.25ter
“command” state or “on-line command” state.
The “Text” and “PDU” modes are not in themselves V.25ter states but are simply sets of commands which
will operate in either the V.25ter “command” state or “on-line command” state. The “Text” and “PDU”
modes are transitory states and after each operation, control is automatically returned to the V.25ter
“command” state or “on-line command” state. Whilst in the V.25ter command state, the MS is available to
handle incoming and outgoing calls such as Data or Facsimile.
V.25ter
"com m and" state
and "on-line com m and" state
SM S SM S
Text PDU
Mode Mode
SM S Block Mode
Figure 0.1/GSM 07.05: Block, Text and PDU modes

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
0.1 Normative references
This ETS incorporates by dated and undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply
to this ETS only when incorporated in it by amendment or revision. For undated references, the latest
edition of the publication referred to applies.
[1] GSM 01.04 (ETR 100): "Digital cellular telecommunication system (Phase 2);
Abbreviations and acronyms".
[2] GSM 03.38 (ETS 300 628): "Digital cellular telecommunication system
(Phase 2); Alphabet and language specific information".
[3] GSM 03.40 (ETS 300 536): "Digital cellular telecommunication system
(Phase 2); Technical realization of the Short Message Service (SMS) Point to
Point (PP)".
[4] GSM 03.41 (ETS 300 537): "Digital cellular telecommunication system
(Phase 2); Technical realization of Short Message Service Cell Broadcast
(SMSCB)".
[5] GSM 04.08 (ETS 300 557): "Digital cellular telecommunication system
(Phase 2); Mobile radio interface layer 3 specification".
[6] GSM 04.11 (ETS 300 559): "Digital cellular telecommunication system
(Phase 2); Point-to-Point (PP) Short Message Service (SMS) support on mobile
radio interface".
[7] GSM 04.12 (ETS 300 560): "Digital cellular telecommunication system
(Phase 2); Short Message Service Cell Broadcast (SMSCB) support on the
mobile radio interface".
[8] GSM 07.01 (ETS 300 582): "Digital cellular telecommunication system
(Phase 2); General on Terminal Adaptation Functions (TAF) for Mobile Stations
(MS)".
[9] GSM 07.07 (ETS 300 642): "Digital cellular telecommunication system
(Phase 2); AT command set for GSM Mobile Equipment (ME)”.
[10] GSM 11.11 (ETS 300 608): "Digital cellular telecommunication system
(Phase 2); Specification of the Subscriber Identity Module - Mobile Equipment
(SIM - ME) interface".
[11] CCITT Recommendation V.25ter: “Serial Asynchronous Automatic Dialling And
Control”.
[12] CCITT Recommendation V.24: "List of definitions for interchange circuits
between data terminal equipment (DTE) and data circuit-terminating equipment".
[13] CCITT Recommendation E.164: "Numbering plan for the ISDN era".
[14] CCITT Recommendation E.163: "Numbering plan for the international telephone
service".
0.2 Abbreviations
Abbreviations used in this ETS are listed in GSM 01.04 [1].

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
1 Reference configuration
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Figure 1: Reference configuration
The mobile termination consists of the mobile equipment (ME) and the SIM. Messages may be stored in
either, but this specification does not distinguish between messages stored in the SIM or in the ME. The
management of message storage in the two parts of the mobile termination is a matter for the mobile
termination implementation.
1.1 V.24 Interface Circuits
The operation of the CCITT V.24 blue book interface circuits for SMS is shown in table 1.1/GSM 07.05.
Table 1.1/GSM 07.05: Use of V.24 interface circuits
V.24 CIRCUIT DESCRIPTION TE to MT MT to TE
CT102 signal ground x x
CT103 TXD x
CT104 RXD x
CT105 RTS x
CT106 CTS x
CT107 DSR x
CT108.2 DTR x
CT109 DCD x
NOTE: CT105 at the TE is connected to CT133 at the MT
1.1.1 Circuit definitions for the SMS Block mode
CT103
All commands from the TE to the MT are transferred across this circuit. Inband flow control is not
permitted during Block Mode.
CT104
All responses/indications from the MT to the TE are transferred across this circuit. Inband flow control is
not permitted during Block Mode.

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
CT105
This circuit allows the TE to flow control the MT when in the Block Mode and at other times if hardware
flow control is enabled.
CT106
This circuit allows the MT to flow control the TE when in the Block Mode and at other times if hardware
flow control is enabled.
CT107
This circuit shall be set to the ON condition before entry into the Block Mode, and shall remain in the ON
condition during Block Mode. If the TE detects that this circuit returns to the OFF condition during the block
mode then the TE shall return CT108.2 to the OFF condition and exit the Block Mode.
CT108.2
This circuit shall be set in the ON condition before the AT+CESP command is sent from the TE to begin the
Block Mode, and shall be maintained in the ON condition during the Block Mode. It shall be returned to the
OFF condition after the command 'END SMS MODE' has been accepted and acknowledged by the MT. If
the MT detects that this circuit returns to the OFF condition during the Block Mode then the MT shall exit
the Block Mode.
CT109
This circuit shall be set to the ON condition before entry into the Block Mode and remain in the ON
condition during the Block Mode. If the TE detects that this circuit returns to the OFF condition during the
Block Mode then the TE shall return CT108.2 to the OFF condition and shall exit the Block Mode.
1.1.2 Circuit definitions for the SMS Text and PDU modes
Only circuits CT102, CT103 and CT104 are mandatory for the Text and PDU modes. The functionality and
operation of other circuits shall be in accordance with V.25ter.

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2 SMS Block Mode
2.1 Beginning and ending of SMS/CBS Block Mode
2.1.1 Beginning SMS/CBS Block Mode
As described in TS GSM 07.01, the DTE/DCE interface is normally associated with the terminal adaptation
function (TAF), if such a function is available. When no data connection is in progress, and the terminal
equipment wishes to enter SMS/CBS mode, the command 'AT+CESP' shall be issued by the TE through
the DTE/DCE interface requesting that the Block mode protocol described in this specification is to be
used. The syntax of this command is further described in section 3.2.4 later. The syntax for these
commands is derived from V.25ter, i.e. the command is encoded as an IA5 character string together with
delimiters as described in V.25ter.
Upon receipt of this command, the mobile termination shall respond as follows:
If the mobile termination supports SMS/CBS block mode commands, responses and indications as
described in this technical specification, it shall respond with 'OK' and enter the SMS/CBS mode.
If the mobile termination does not support SMS/CBS block mode commands, responses and
indications as described in this technical specification, it shall respond with 'ERROR' and remain in
the current mode.
If the SMS/CBS block mode command is accepted by the mobile termination, then all further commands,
responses and indications shall be as defined in section 2 of this technical specification. These SMS/CBS
mode commands, responses and indications use 8-bit encoded data and not IA5 characters.
2.1.2 Returning from SMS/CBS Block Mode To Default Mode
When the terminal equipment wishes to return to default mode from SMS/CBS mode, it shall issue the
command 'END SMS MODE', described in section 2.4.1.11. The mobile termination shall respond with 'OK'
to indicate that the DTE/DCE interface has returned to default mode. The TE shall change back to default
mode whether or not such a response is received.
The TE may also indicate that it has exit from the SMS/CBS mode through the use of CT 108/2 (see
section 1.1)
If an incoming data call arrives while the DTE/DCE interface is set to SMS/CBS mode, then the mobile
termination may autonomously issue the 'END SMS MODE' indication (section 2.4.2.11) and revert to
default mode in order to connect the data call through the TAF.
The MT may exit from SMS/CBS mode autonomously if the power to the MT is switched off and then on
again. In addition, the MT manufacturer may provide MMI to change the mode back to the default mode.
In the latter case, the MT shall issue the 'END SMS MODE' indication (section 2.4.2.11) and exit the
SMS/CBS mode immediately.
The MT may also indicate that it has exit from the SMS/CBS mode through the use of CT 107 and
CT 109 (see section 1.1).
A BREAK condition in either direction at the DTE/DCE interface shall cause the TE and the MT to exit from
the SMS/CBS block mode and return to the default mode.
In the event where the TE or the MT find themselves unable to recover from a protocol error then either
entity may exit the SMS/CBS mode using any of the mechanisms described above. Confirmation of default
mode operation will be achieved through the use of AT commands and responses.

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ETS 300 585: September 1996 (GSM 07.05 version 4.6.0)
2.2 Protocol description
The communication path between the MT and the TE across the DTE/DCE interface should be quite
reliable if it uses a short wire link. However, to ensure that the low error rate does not cause malfunction,
the following error protection scheme is provided.
Each message sent from the MT to the TE or vice-versa consists of a data block (DATA) and block check
sum (BCS, see figure 2.2.1). In the following description the notation DLE, STX, NUL and ETX refer to
control characters having the values 10 02 00 and 03 hexadecimal respectively.
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Figure 2.2.1/GSM 07.05: Format of DTE/DCE interface messages
The data block consists of a start transmission sequence, set to 00010000 00000010 (10 02 hex), the
message content as defined below and an end transmission sequence, set to 00010000 00000011 (10 03
hex). The least significant bit of each octet is always transmitted first.
The block check sum is calculated at the transmitter by adding all of the octets in the message content
modulo 65536. Each bit of the 16-bit result is then inverted, and 1 is added to the answer.
During transmission of the message content and the BCS octets, any occurrence of the value 10 hex (DLE)
shall result in an additional 'stuffing' octet of value 00 hex (NUL) being transmitted immediately following the
octet containing 10 hex. This is to ensure that the start and end markers are unambiguous. The receiver
shall remove stuffing octets by discarding any octet of value 00 hex (NUL) which immediately follows an
octet of value 10 hex (DLE).
After removal of any stuffing octets, the receiver can check the BCS by adding all of the octets in the
message content and the 16-bit BCS modulo 65536. The correct result is 0000 hex. If any message is
received with an incorrect BCS, then the message is discarded. No response is sent over the DTE/DCE
interface, but an indication may be provided to higher layers within the receiv
...