Asynchronous Facsimile DCE Control Standard, Service Class 1

TIA/EIA-578-B

Facsimile Digital Interfaces -

Asynchronous Facsimile DCE Control Standard, Service Class 1

CONTENTS

1 Introduction & Scope 1

1.1 Facsimile Terminals 1

1.2 Facsimile DCE 1

1.3 Scope 1

2 Overview 2

2.1 Service Class 1 2

2.2 Service Class 2 2

2.3 Service Class 3 (for further study) 2

2.4 Service Class 4 (for further study) 2

3 Normative References 3

4 Definitions 4

5 Facsimile DTE-DCE Interchange Circuits 4

5.1 DTE-DCE Communication Link Data Rates 5

5.2 Asynchronous to Synchronous conversion 5

5.3 Flow Control 5

5.4 Serial Data Interchange Circuits 6

5.4.1 Optional circuit behaviour 6

6 Autodialer Services 6

6.1 Command Syntax 6

6.2 Command execution 7

6.2.1 Command execution time 7

6.2.2 Aborting commands 7

6.3 Response Syntax 7

6.4 Capabilities Identification & Control 8

6.5 Call Answering 8

6.6 Call Origination 8

6.7 Call Termination 8

6.8 Result Codes 8

6.9 Serial Port Flow Control 9

6.10 Serial Port Speed Control 9

6.11 Transparent Data Commands 10

6.11.1 DTE to DCE streams 10

6.11.2 DCE to DTE streams 10

7 Facsimile Service Class 1 10

7.1 Connection Establishment 11

7.1.1 Answer Connection 11

7.1.2 Originate Connection 11

7.2 Waiting and Silence Detection 11

7.2.1 Waiting 11

7.2.2 Silence Detection 12

7.3 Data Transfer 12

7.4 HDLC Framing, Transparency, and Error Detection 12

7.5 Facsimile Carrier Error Message Response 12

8 Service Class 1 Commands and Responses 12

8.1 Command Summary 13

8.2 Capabilities Identification and Control 14

8.2.1 Service Class Indication, +FCLASS? 14

8.2.2 Service Class Capabilities, +FCLASS=? 14

8.2.3 Service Class Selection, +FCLASS=<value> 14

8.2.4 Request DCE Identification 15

8.3 Service Class 1 Action Commands 15

8.3.1 Transmit Silence, +FTS=<Time> 15

8.3.2 Receive Silence, +FRS=<Time> 15

8.3.3 Facsimile Transmit, +FTM=<MOD> 16

8.3.4 Facsimile Receive, +FRM=<MOD> 16

8.3.5 HDLC Transmit, +FTH=<MOD> 17

8.3.6 HDLC Receive, +FRH=<MOD> 17

8.4 Service Class 1 Result Code 18

8.5 Class 1 Parameters 18

8.5.1 Flow Control Select, +FLO 19

8.5.2 Serial Port Rate Control, +FPR 19

8.5.3 Double Escape Character Replacement, +FDD 20

8.5.4 Adaptive reception control (+FAR) 21

8.5.5 Carrier loss time-out, +FCL 21

8.5.6 DTE inactivity time-out, +FIT 21

ANNEX A (Informative) Service Class 1 Example Sessions 24

A.1 Calling Sequence, Transmitting a Single Page Facsimile 24

A.2 Answering and Receiving a Single Page Facsimile 26

ANNEX B (Informative) Recommendations for DTE Compatibility 28

B.1 Introduction 28

B.2 Clarification of +FTM Command, 8.3.3 28

B.3 Clarification of +FTH Command, 8.3.5 29

B.4 Clarification of Switching from HDLC Reception to Transmission 29

B.5 Clarification of Switching Transmit Modulation Schemes 30

B.6 Clarification of Abnormal Termination of Reception 30

B.7 Lack of Default Flow Control Method 30

Annex C (Informative) Interworking with standard DTE 32

Annex D (Normative) - Procedure for Service Class 1 support of V.34 modems 34

D.1 Introduction 34

D.1.1 V.34 Modems 34

D.1.2 T.30 procedures for use with V.34 modems 34

D.1.3 V.8 call negotiation 34

D.2 References 34

D.3 Functions 35

D.4 Definitions and Conventions 35

D.5 Transparent Data Commands 35

D.6 Initial V.34 Rate controls and indications 36

D.6.1 Initial V.34 rate controls, +F34 parameter 36

D.6.2 Initial V.34 rate indication 37

D.7 DTE-DCE Data 38

D.7.1 DTE to DCE messages 38

D.7.2 DCE to DTE messages 38

D.7.3 HDLC frame data 38

D.8 Source terminal procedures 38

D.8.1 Transition from V.8 negotiation 38

D.8.2 Initiate sending procedures 39

D.8.3 Terminate sending procedures 39

D.8.4 Half-duplex modem channel selection 40

D.8.5 Half-duplex primary rate renegotiation 40

D.8.6 Duplex rate negotiation 41

D.8.7 V.34 Retrain 41

D.9 Message Reception, ATO 41

D.9.1 Transition from V.8 negotiation 41

D.9.2 Initiate reception procedures 41

D.9.3 Terminate reception procedures 42

D.9.4 Half-duplex modem channel indication 42

D.9.5 Half-duplex primary rate renegotiation 43

D.9.6 Duplex rate negotiation 43

D.9.7 V.34 retrain 43

D.9.8 Turn around polling 43

D.10 Sample sessions. 43

D.10.1 Originate and send a 2-page facsimile with V.34 half duplex 45

D.10.2 Answer and receive a 2-page facsimile with V.34 half duplex 46

D.10.3 Control channel retrain 49

D.10.4 Originate and do initial polling 51

D.10.5 Turnaround polling 52

Annex E (Informative) Differences from EIA/TIA 578A 56

(This foreword is not part of this Standard)

FOREWORD

This Standard was prepared by the Telecommunications Industry Association Technical Subcommittee TR-29.2, Facsimile Digital Interfaces.

A device that conforms to this Standard may commonly implement the services and procedures defined in ANSI/TIA/EIA-602, Data Transmission Systems and Equipment - Serial Asynchronous Automatic Dialing and Control. It may also implement services and procedures defined in ANSI/TIA/EIA-592, Asynchronous Facsimile DCE Control Standard, Service Class 2 or TIA/EIA IS-101, Voice Control Interim Standard for Asynchronous DCE. It may also implement the similar ITU recommendations T.31 (Class 1 facsimile), T.32 (Class 2 Facsimile) and V.250 (data modems).

This is the second revised version of this Standard, previously issued as ANSI/EIA/TIA-578-A-1994, Asynchronous Facsimile DCE Control Standard, Service Class 1. It incorporates optional improvements developed in other work, particularly in ITU T.31 and V.250. It also incorporates informative material accumulated when this standard was implemented and problems were identified, previously published in TIA TSB-43, Recommendations for DTE Compatibility with EIA/TIA-578 DCEs and Corrections to Example Sessions as Annex B in this standard.

It is the intention of the formulating committee that all modifications, additions and clarifications keep this revision completely backward compatible with DCEs compliant with EIA/TIA-578-1990, and EIA/TIA-578-A-1994.

i

TIA/EIA-578-B

1 Introduction & Scope

1.1 Facsimile Terminals

Group 3 Facsimile machines were developed for sending digitized documents over the General Switched Telephone Network (GSTN). These facsimile terminals are now in widespread use around the world.

The operation of Group 3 Facsimile terminals has been standardized in ITU-T Recommendations T.4, T.6 and T.30.

1.2 Facsimile DCE

There are two types of adapters which allow data terminal equipment (DTE) to communicate as Group 3 facsimile terminals. Some of these adapters are installed inside the DTE, on the processor bus; these are called "FAX boards". Others are configured as an external "facsimile DCE", connected to the DTE by a standard serial port (e.g. EIA/TIA-232-E, ITU-T V.24), using serial data interchange.

1.3 Scope

This standard contains protocols for use between a DTE and a Facsimile DCE. It includes automatic calling and answering.

This standard defines the commands that the DTE may issue to configure and control the DCE, and the responses the facsimile DCE may issue to those commands.

This standard is useful for intelligent DTEs and DTE software, facsimile DCEs, facsimile terminals, and Multi-Functional Devices with digital connection to DTEs.

This standard assumes that the DTE and DCE are connected via serial asynchronous connection using EIA/TIA-232-E (or ITU-TITU V.24) circuits. However, the protocols defined may be implemented in any environment that provide a character serial bi-directional data stream, including processor bus attached "fax boards", local area networks, Small Computer Systems Interface (SCSI, ANSI X3.131), IEEE 1284 parallel ports, etc. The adaptation of the protocols and procedures to these alternative communication schemes is for future study.

2 Overview

A system including a DTE and a facsimile DCE partitions Group 3 facsimile functions between the two devices. There are several levels in the communications path where a functional partition can be made. This standard describes protocols for use at one of those levels, Service Class 1. Each level is described as a "Service Class" based on the functions performed by the DCE.

2.1 Service Class 1

Section 7 of this document describes a set of services at the physical and data link layers: waiting, signaling, and HDLC data formatting. ITU-T T.30 session management and ITU-T T.4 image data handling are done by the DTE.

2.2 Service Class 2

TIA/EIA-592, Asynchronous Facsimile DCE Control Standard, Service Class 2, describes a facsimile DCE which provides a set of services described by ITU-TITU-T Recommendation T.30. The facsimile DCE makes and terminates calls, manages the communication session, and transports image data. The DTE prepares and interprets image data in compressed form, as described in ITU-T recommendation T.4.

2.3 Service Class 3 (for further study)

A Service Class 3 facsimile DCE converts image file data into ITU-T T.4 compressed images for transmission, and may reverse the conversion on reception.

2.4 Service Class 4 (for further study)

A Service Class 4 DCE contains similar services to those described by this standard. In addition, it defines an improved mechanism for DTE-Facsimile DCE interaction, including an on-line data mode where commands are embedded within the data stream, and DTE commands and DCE responses are buffered; this mode can provide substantial relief from DTE critical timing in those environments where the DTE cannot maintain the responsiveness necessary to support a Service Class 1 DCE.

3 Normative References

The following standards contain provisions which, through reference in this text, constitute provisions of this Interim Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. ANSI and TIA maintain registers of currently valid national standards published by them.

ANSI/EIA/TIA-232-E, Interface between data terminal equipment and data communication equipment employing serial binary data interchange on unbalanced circuits.

ANSI/TIA/EIA-592-1992, Asynchronous Facsimile DCE Control Standard, Service Class 2

ANSI/TIA/EIA-602-1992, Serial Asynchronous Automatic Dialing and Control

ANSI/TIA/EIA-615-1992, Serial Asynchronous Automatic Dialing and Control - Extended Command Syntax

TIA/EIA IS-101-1993, Facsimile Digital Interfaces - Voice Control Interim Standard for Asynchronous DCE.

ITU-T() T.4-1993, Standardization of Group 3 Facsimile Apparatus for Document Transmission.

ITU-T() T.30-1993, Procedures for Document Facsimile Transmission in the General Switched Telephone Network.

ITU-T T.31-1995, Serial Asynchronous Facsimile DCE Control, Service Class 1

ITU-T T.32-1995, Serial Asynchronous Facsimile DCE Control, Service Class 2

ITU-T Recommendation T.50 (1992), International Reference Alphabet (IRA) (formerly International Alphabet No. 5 or IA5) – Information technology – 7-bit coded character set for information interchange.

ITU-T Recommendation V.4, General Structure of signals of International Alphabet Number 5 code for data transmission over public telephone network.

ITU-T Recommendation V.8 (1994), Procedures for starting and ending sessions of data transmission over the general switched telephone network.

ITU-T Recommendation V.17, 14400 bit/s 2-wire modem standardized for use in Facsimile Applications.

ITU-T Recommendation V.21, 300 bit/s duplex modem standardized for data transmission over the general switched telephone network.

ITU-T Recommendation V.24, List of definitions for interchange circuits between data terminal equipment and data circuit terminating equipment.

ITU-T Recommendation V.25, Automatic Calling and/or Answering equipment on the GSTN, including disabling of echo suppressers on manually established calls.

ITU-T Recommendation V.250 - 1995, Serial Asynchronous Automatic Dialing and Control

ITU-T Recommendation V.27ter, 4800/2400 bit/s modem standardized for use in the general switched telephone network.

ITU-T Recommendation V.29, 9600 bit/s modem standardized for use on point-to-point leased telephone-type circuits.

ITU-T Recommendation V.33, 14400 bit/s modem standardized for use on point-to-point 4-wire leased telephone-type circuits.

ITU-T Recommendation V.34 (1996), A modem operating at data signaling rates of up to 33 600 bit/s for use on the general switched telephone network and on leased point-to-point 2-wire telephone-type circuits.

ISO 646, 7 bit coded character set for information processing interchange.

ISO 21111972, Data communication Basicmode control procedures Code independent information transfer.

4 Definitions

For the purposes of this standard, the following definitions shall apply:

DTE, Data Terminal Equipment A DTE is any terminal or computer capable of providing commands and data to operate a DCE or facsimile DCE. In practice, these are computers of any size.

DCE, Data Circuit Terminating Equipment A DCE is any device that connects a DTE to a communications network. This standard focuses on DCEs which connect to the General Switched Telephone Network (GSTN). This class of DCEs includes DCEs compatible with the ITU-T V Series modem recommendations and facsimile DCEs described below.

Facsimile DCE A facsimile DCE is a device which provides facsimile communication facilities between a DTE and the GSTN. A Class 1 facsimile DCE includes the following functions:

Control Functions

Interchange circuits to the DTE

HDLC Data Link Layer Functions

V Series Signal converters

Autodialer Functions

GSTN Interface

Facsimile DTE A facsimile DTE must provide those Group 3 facsimile functions and services not provided by the facsimile DCE. The specific implementation of these functions is beyond the scope of this standard.

5 Facsimile DTE-DCE Interchange Circuits

A facsimile DCE described by this standard uses an asynchronous serial connection between the DTE and the DCE. Typically, serial data is formatted in 10 bit character frames, including a start bit, 8 data bits, no parity and 1 stop bit. Use of this protocol on other DTE-DCE interfaces is beyond the scope of this standard.

5.1 DTE-DCE Communication Link Data Rates

The DTE-facsimile DCE communications link shall provide full duplex character data at rates fast enough to accommodate the transfer of synchronous T.30 Phase C data. A data rate greater than or equal to 18,000 bit/s (e.g. 19,200 bit/s) is the minimum rate needed to support 14,400 bit/s V.17 Phase C data. A data rate greater than or equal to 42,000 bit/s is the minimum rate needed to support 28,800 bit/s V.34 Phase C data. With flow control, it is not necessary, and not recommended, to change the DTE-DCE communications link data rate during facsimile operation. Mechanisms to set the DTE-DCE serial rate are described in 6.10 and 6.2.10/V.25ter (IPR parameter).

5.2 Asynchronous to Synchronous conversion

Group 3 data communication is bit-synchronous. The DCE must delete start and stop elements from these characters before transmission and add them to received octets. Bit sequencing is maintained between the DTE-DCE interface and the DCE-remote station interface, as specified in T.4 and T.30.

5.3 Flow Control

Flow control is necessary to match the DTE-DCE data rate to the line signaling rate and to the requirements of Group 3 data transmission. (For example, provision must be made for minimum scan line times.) Provision of in-band unidirectional DC1/DC3 (XON/XOFF) flow control is mandatory; flow control using V.24 circuits 106 and 133 is optional.