1、ANSI INCITS 187-1990 (R2001) (formerly ANSI X3.187-1990 (R2001)for Information Systems Recorded Magnetic Tape forLongitudinal Recording ofInstrumentation Data InterchangeANSI X3.1 87-1990 American National Standard for information Systems - Recorded Magnetic Tape for Longitudinal Recording of Instru
2、mentation Data - Interchange Secretariat Computer and Business Equipment Manufacturers Association Approved August 21,199O American National Standards Institute, Inc. AmericanNationalStandardApproval of an American National Standard requires review by ANSI that therequirements for due process, conse
3、nsus, and other criteria for approval havebeen met by the standards developer.Consensus is established when, in the judgment of the ANSI Board of StandardsReview, substantial agreement has been reached by directly and materiallyaffected interests. Substantial agreement means much more than a simplem
4、ajority, but not necessarily unanimity. Consensus requires that all views andobjections be considered, and that a concerted effort be made toward theirresolution.The use of American National Standards is completely voluntary; their existencedoes not in any respect preclude anyone, whether he has app
5、roved the standardsor not, from manufacturing, marketing, purchasing, or using products, processes,or procedures not conforming to the standards.The American National Standards Institute does not develop standards and will inno circumstances give an interpretation of any American National Standard.M
6、oreover, no person shall have the right or authority to issue an interpretation ofan American National Standard in the name of the American National StandardsInstitute. Requests for interpretations should be addressed to the secretariat orsponsor whose name appears on the title page of this standard
7、.CAUTION NOTICE: This American National Standard may be revised orwithdrawn at any time. The procedures of the American National StandardsInstitute require that action be taken periodically to reaffirm, revise, or withdrawthis standard. Purchasers of American National Standards may receive currentin
8、formation on all standards by calling or writing the American National StandardsInstitute.Published byAmerican National Standards Institute11 West 42nd Street, New York, New York 10036Copyright 1991 by Information Technology Industry Council (ITI)All rights reserved.No part of this publication may b
9、e reproduced in anyform, in an electronic retrieval system or otherwise,without prior written permission of ITI, 1250 Eye Street NW,Washington, DC 20005.Printed in the United States of AmericaContents Page Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii 1 introduction 1 2 Normative references .2 3 Definitions 2 4 General considerations for longitudinal recording . .5 5 Recorded tape . 6 6 Head and head segment mec
11、hanical parameters .7 7 Head polarity . 7 8 Direct-record and reproduce systems .7 9 Timing signal recording . 8 10 Predetection recording 9 11 Tape signature recording 9 12 FM record systems .9 13 PCM recording 10 14 Recording without bias . .10 Tables 4 5 6 7 8 9 10 11 Record and reproduce paramet
12、ers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Standard tape widths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
13、 Dimensions - Recorded tape format, 4 tracks in-line on 6.3-mm- (l/4-in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Dimensions - Recorded tape format, 7 tracks i
14、nterlaced on 6.3- mm- (l/4-in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Dimensions - Recorded tape format, 7 tracks interlaced on 12.7 mm- (l/2-in-) wide tape . . . . . . . . .
15、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Dimensions - Recorded tape format, 14 tracks interlaced on 12.7- mm- (i/2-in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Dimensions - Recorded tape format, 21 tracks interlaced on 12.7- mm- (l/2-in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17、. . . . . . . . 16 Dimensions - Recorded tape format, 14 tracks interlaced on 25.4- mm- (1 -in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Dimensions - Recorded tape format,
18、 14 tracks in-line on 25.4-mm- (1 -in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Dimensions - Recorded tape format, 28 tracks interlaced on 25.4- mm- (1 -
19、in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Dimensions - Recorded tape format, 42 tracks interlaced on 25.4- mm- (1 -in-) wide tape . . . . . . . . . . . . . . . . . . .
20、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 12 Dimensions - Recorded tape format, 84 tracks interlaced on 50.8- mm- (2-in-) wide tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 13 Constant-amplitude speed-control signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 14 Predetection carrier parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
22、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 15 Intermediate, wideband, and double-density FM record parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
23、. . . . . . . . . . 26 Figures 1 Recorded tape format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2 Head and head segment mechanical parameters . . . . . . . . . . . . . . . . . . . . .
24、 . . . . . . . . . . 28 3 Record and reproduce head and head segment identification and location (7-track interlaced system) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4 Record and reproduce head and segment identification and loca-
25、 tion (N-track interlaced system) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 5 Recorded tape format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26、. . . . . . . . . . . . . . . . . . . 31 Annexes A Test procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 B Bibliography . . . . . . _ 62 ii Foreword (This Fore
27、word is not part of American National Standard x3.1 87-1990.) This standard presents format and recording requirements for interchange of analog data on instrumentation magnetic tape having nominal width of 0.25 inch, 0.5 inch, 1 inch, and 2 inches. This standard deals solely with recording on instr
28、umentation magnetic tape and is complemented by Ameri- can National Standard for Information Systems-Unrecorded Magnetic Tape for Longitudinal Recording of Instrumentation Data-Interchange.* This standard is similar but not identical to the applicable parts of IRIG Standard 106-86, Telemetry Standar
29、ds. The X3B6 subcommittee, which developed this standard, contains highly experienced representatives of the users, manufacturers, and general interest communities. In developing this standard, careful consideration was given to using the best and most current engineering practices, gaining maximum
30、acceptance, and providing a basis for future improvement in the use of the medium. This standard contains two informative annexes which are not considered part of the standard. Suggestions for improvement of this standard are welcome. They should be sent to the Computer and Business Equipment Manufa
31、cturers Association, 311 First Street, NW, Suite 500, Washington, DC 20001-2178. This standard was processed and approved for submittal to ANSI by Accredited Standards Committee on Information Processing Systems, X3. Committee approval of this standard does not necessarily imply that all committee m
32、embers voted for its approval. At the time it approved this standard, the X3 committee had the following members: Richard Gibson, Chair Donald C. Loughry, Vice-Chair Jean-Paul Emard, Administrative Secretary Organization Represented Name of Representative Allen-Bradley Company . . . . . . . . . . .
33、. . . . . . _. . . . . . . . . . . . . . . . . . . . . . . . . . . . Ronald H. Reimer Jon Lenner (Alt.) American Library Association . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I . . . . . . . . 1:. . . . . :.:I . . . . . . . . . . . . Paul Peters American Nuclear Soc
34、iety . . . . . . . . . . . . . Geraldine C. Main AMP, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Edward Kelly Patrick Lannon (Alt.) Apple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
35、 . . . . . . . . . . Karen Higginbottom Michael J. Lawler (Alt.) Association of the Institute for Certification of Computer Professionals . . . . . . . . . . Kenneth Zemrowski Eugene M. Dwyer (Alt.) AT for example, a 0 level is present when a 1 is expected, or a 1 level is present when a 0 level is
36、expected. 3.4 bit error rate (BER): Number of bits in error in a predetermined number of bits trans- mitted or recorded; for example, 1 in lo6 or a BER of 1O-6 3.5 bit packing density, linear: Number of bits recorded per inch or per millimeter of tape length. For serial PCM recording, the number of
37、bits per unit length of a single track. 3.6 bit slip: The increase or decrease in detected bit rate by one or more bits with respect to the actual bit rate. 3.7 cross-play: Reproducing a previously recorded tape on a recorder and reproducer system other than that used to record the tape. 3.8 cross-t
38、alk: Undesired signal energy ap- pearing in a reproducer channel as a result of coupling from other channels. 3.9 data azimuth 3.9.1 general: Angle in the plane of the tape, at any instant in time, between a line perpen- dicular to the reference edge of the tape and either of the two parallel lines
39、defining data scatter. NOTE-Data azimuth may be expressed as the sum of static and dynamic components in the form: 2, Available from the American National Standards Institute, 11 West 42nd Street, New York, NY 10036. 2 ANSI X3.1 87-l 990 A + W(O where Ojf( t)dt = 0 3.9.2 data azimuth (dynamic): Maxi
40、mum angular deviation, over a period of time, of the data azimuth from its mean value as defined by data azimuth (static). For the purposes of this definition, the word “maximum” is interpreted as being at the 95 percent probability level. For a Gaussian distribution, this is two standard deviations
41、 (20). NOTE-Data azimuth (dynamic) is the maximum value of the quantity Bf(t) in the note on data azimuth. 3.9.3 data azimuth (static): Mean value, over a period of time, of the data azimuth. 3.10 data scatter: The distance between two parallel lines (as defined under gap scat- ter) in the plane of
42、the tape, which contains all data transitions recorded simultaneously with the same head, at the same instant of time. 3.11 data spacing: For interlaced head systems, the distance on tape between simul- taneous events recorded on odd and even heads. 3.12 direct recording (ac bias recording): A magne
43、tic recording technique employing a high-frequency bias signal that is linearly added to the data signal. The composite signal is then used as the driving signal to the record- head segment. The bias signal, with a fre- quency well above the highest frequency that can be reproduced by the system, tr
44、ansforms the recording of the data signal to a more nearly linear process. 3.13 double-density recording: Direct, FM, or PCM recording on magnetic tape at bandwidths equal to those used in wideband instrumentation recording, but at one-half the wideband tape speeds (see table 1). Special record and
45、reproduce heads and high-output tapes are required for double-density record- ing. 3.14 dropout: An instantaneous abnormal reproduce signal amplitude that may cause data errors. 3.15 edge margin: The distance between the outside edge of the highest number track and the tape edge (see figure 1). 3.16
46、 edge margin minimum: The minimum allowable value of edge margin. 3.17 FM recording: Recording on magnetic tape using frequency-modulated record elec- tronics to obtain response from dc to an upper- specified frequency. FM systems forfeit upper bandwidth response of direct-record systems to obtain l
47、ow-frequency and dc response not available with direct recording. 3.18 flux transition: A 180-degree change in the flux pattern of a magnetic medium, brought about by a reversal of poles within the medium. 3.19 flux transition density: Numberof flux transitions per millimeter (mm) or per inch (in) o
48、f track length. 3.20 flutter: Undesired changes in the fre- quency of signals during the reproduction of a magnetic tape produced by speed variations of the magnetic tape during recording or repro- ducing. 3.21 gap length (physical): The dimension between leading and trailing edges of a record or re
49、produce head-segment gap measured along a line perpendicular to the track width. 3.22 gap scatter (record head): The dis- tance between two parallel lines defined as follows: a) The two lines pass through the geometric centers of the trailing edges of the two out- ermost head segment gaps within a record head. The geometric centers of the other head segment gap trailing edges lie be- tween the two parallel lines. b) The two parallel lines lie in the plane of the tape and are perpendicular to the head reference plane (see figure 2). 3.23 gap scatter (reproduce head): De- fined as for
