ISO 6983-1:2009

INTERNATIONAL ISO
STANDARD 6983-1
Second edition
2009-12-15
Automation systems and integration —
Numerical control of machines —
Program format and definitions of
address words —
Part 1:
Data format for positioning, line motion
and contouring control systems
Systèmes d'automatisation industrielle et intégration — Commande
numérique des machines — Format de programme et définitions des
mots adresses —
Partie 1: Format des données pour les systèmes de positionnement, de
commande paraxiale de mouvement et de contourage

Reference number
©
ISO 2009
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ii © ISO 2009 – All rights reserved

Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 Program format.1
5 Format make-up.2
5.1 Data block.2
5.2 Data words .2
5.3 Omitted words .3
6 Words.3
6.1 All words.3
6.2 Address indexing .4
6.3 Dimension words.4
6.4 Non-dimensional words.5
7 Programming methods for interpolation .6
7.1 Principles.6
7.2 Linear interpolation .7
7.3 Circular interpolation .8
7.4 Parabolic interpolation.9
8 Tool length offset and tool offset .11
9 Tool radius (diameter) offset.11
10 Cutter compensation.11
11 Thread cutting.12
12 Constant surface speed.12
13 Dwell .12
14 Reset states .12
14.1 General .12
14.2 Point to point and line motion controls .13
14.3 Contouring controls other than those on lathes.13
14.4 Contouring controls on lathes .13
Annex A (normative) List of characters used from ISO/IEC 646.14
Annex B (normative) General format classification .16
Annex C (normative) Detailed format classification.18
Annex D (normative) Notes for program interchangeability .20
Annex E (normative) Preparatory (G) and miscellaneous (M) function codes.21
Bibliography.26

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 6983-1 was prepared by Technical Committee ISO/TC 184, Automation systems and integration,
Subcommittee SC 1, Physical device control.
This second edition cancels and replaces the first edition (ISO 6983-1:1982), which has been technically
revised.
The following changes have been made to the first edition:
⎯ the content has been restructured in a more logical order;
⎯ the commonly used preparatory (G) and miscellaneous (M) function codes have been grouped in one
standard (see Annex E);
⎯ address indexing has been introduced (see 6.2);
⎯ the equal (=) sign has been added to allow for axis indexing (see 6.2.1);
⎯ new data formats have been specified to existing programming methods: helical interpolation (see 7.3);
dwell time (see Clause 13); thread cutting (see Clause 11).
ISO 6983 consists of the following parts, under the general title Automation systems and integration —
Numerical control of machines — Program format and definitions of address words:
⎯ Part 1: Data format for positioning, line motion and contouring control systems
The following parts are under preparation:
⎯ Part 2: Coding of miscellaneous functions M (class 1 to 8) [Technical Report]
iv © ISO 2009 – All rights reserved

Introduction
ISO 6983 describes a word address program format for machine control programs on different data storages,
e.g. perforated tape, magnetic media, universal serial bus (USB) stick, hard disk, floppy disk, random-access
memory (RAM), etc., or provided from a remote data source. ISO 6983 covers variable block format only and
is not intended to specify machine design.
ISO 6983 is intended to specify the program format for the control program to be used for numerical controls
(NC) on machines/machine tools. However, ISO 6983 can also be used for all kinds of geometric
specifications and interactions with machines.
The program format specified by ISO 6983 is commonly referred to as “G code programming” or “ISO
programming”.
Compliance with ISO 6983 does not guarantee interchangeability of machine control programs between
different machines/machine tools. Annex D details some of the additional considerations necessary to ensure
this interchangeability.
INTERNATIONAL STANDARD ISO 6983-1:2009(E)

Automation systems and integration — Numerical control of
machines — Program format and definitions of address
words —
Part 1:
Data format for positioning, line motion and contouring control
systems
1 Scope
This part of ISO 6983 specifies requirements and makes recommendations for a data format for positioning,
line motion and contouring control systems used in the numerical control of machines. This part of ISO 6983
helps the co-ordination of system design in order to minimize the variety of program manuscripts required, to
promote uniformity of programming techniques, and to foster interchangeability of input programs between
numerically controlled machines of the same classification by type, process, function, size and accuracy. It is
intended that simple numerically controlled machines be programmed using a simple format, which is
systematically extensible for more complex machines.
This part of ISO 6983 is not intended for use in the specialized cases of numerically controlled flame cutting
machines and drafting machines used specifically and exclusively in the shipbuilding industry. In this
application, a related format (“the ESSI Format”) is specified in ISO 6582.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 2806, Industrial automation systems — Numerical control of machines — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 2806 apply.
4 Program format
The machine program shall be structured in blocks of data, which contain sets of commands to the control
system. A block shall consist of a number of words each of which is a specific instruction to the control system.
A character designated “end of block” shall terminate every block of data and in addition shall precede the first
block of data.
A “program start” character shall precede all control data including “end of block”. It is recommended that it
should be used as an “absolute rewind stop” character.
All alphabetic, numeric and special characters shall conform to Annex A. Those characters required for
reproducing a hard copy of the machine program, listed in Annex A as “non printing characters”, shall be
ignored by the control equipment, with the exception of the LF/NL (end of block) character.
If there is any group of characters that is not to be processed in accordance with this part of ISO 6983, this
group shall be within parenthesis characters (control out – control in). Any such group shall not contain either
“:” or “%” characters. This group may be processed for display purposes, e.g. as instructions to an operator.
Where it is necessary to identify a machine program, this identification should be placed immediately after the
program start character and before the first “end of block” character. If the identification contains alpha
characters, the entire identification should be enclosed with parentheses. Where it is desired to identify a
machine program number word, the program
...