ISO INTERNATIONAL 9543 STANDARD First edition 1989-04-01 Information processing systems - Information exchange between systems - : Synchronous transmission signal quality at DTE/DCE interfaces Systemes de traitement de I'information - Echange d'informations entre systemes Qualité des signaux en transmission synchrone a I'interface ETTD/ETCD Reference number ISO 9543 : 1989 (E) Copyright International Organization for Standardization cing permitted without license from IHS Not for Resale ISO 9543 : 1989 (E) 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. Internationat organizations, govern- mental 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISO Council. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 9543 was prepared by Technical Committee ISO/TC 97, Informationprocessing systems Annex A of this International Standard is for information only ISO ? 1989 Alf rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case postale 56 : CH-1211 Geneve 20 · Switzerland Printed in Switzerland Copyright International Organization for Standardization Not for Resale ed without license from IHS INTERNATIONAL STANDARD ISO 9543 : 1989 (E) Information processing systems - Information exchange between systems - Synchronous transmission signal quality at DTE/DCE interfaces 1 Scope organizations. It does not attempt to indicate what action, if any, is to be taken if the limits are not met, but it is intended to provide a basis for agreement between parties involved. This International Standard specifies signal quality re- 1.1 quirements for serial data transmission at the interface between synchronous transmission Data Terminal Equipment (DTE) and 1.4This tnternational Standard does not describe the signal Data Circuit-terminating Equipment (DCE). The interface re- quality of the DCE or the line associated with it. Neither does it ferred to in this International Standard conforms to CCITT describe any requirement for an acceptable bit error rate. Recommendations V.24 (telephone networks), X.24 (data net- works) as specified in DCEs of CCITT Recommendations : 1.5 This International Standard may also be used for DTE to DTE direct connections when the referenced CCITT Interfaces V.22, V.22bis, V.23, V.26. V.26bis, V.26ter, V.27, V.27bis, are applied. V.27ter, V.29, V.32, V.33, or X.21bis together with V.28, electrical characteristics; or Normative references 2 V.35 together with V.28/V.35 electrical characteristics; or The following standards contain provisions which, through reference in this text, constitute provisions of this International! V.36, V.37 or X.21 together with V.10/V.11, electrical Standard. At the time of publication, the editions indicated characteristics; or were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged X.22 together with V.11, electrical characteristics. to investigate the possibility of applying the most recent editions of the standards indicated below. Members of tEC and It is also r