1、STD-ECMA ECMA-152-ENGL 1993 m 3404593 0032959 TBL m ECMA EUROPEAN COMPUTER MANUFACTURERS ASSOCIATION STANDARD ECMA-152 DATA INTERCHANGE ON 12,7 IIII 18mTRACK MAGNETIC TAPE CARTRIDGES = EXTENDED FORMAT = 2nd Edition - December 1993 Free copies of this document are available from ECMA, European Comput
2、er ManufaciUrers Association, 114 Rue du Rhne - CH-I204 Geneva (Switzerland) Phone: 41 22 735 36 34 Fax: 41 22 786 52 31 X.400: C=ch, A=arcom, *ma, *genevanet, OU l=ecma, S=help b) specify a method for identifying whether the recorded data has been processed and, if it has been processed, the algori
3、thm used for processing: c) specify a method for including recorded data blocks conforming to this Standard and recorded data blocks conforming to Standard ECMA-120 on the same tape. The permissible routes for the flow of data are shown in annex J. 2 Conformance 2.1 Magnetic tape cartridge A magneti
4、c tape cartridge shall be in conformance with this Standard if: a) b) c) the cartridge meets all the requirements of clauses 4 and 6 to 8; the recording on the tape meets the requirements of clauses 9 to 13; for each recorded packet the algorithm used for processing the data therein, if processed da
5、ta has been recorded, has (have) been registered and the registered identification is included in Byte 13 of the Packet ID Block of this packet (see 11.2). 2.2 Generating system A system generating B magnetic tape cartridge for interchange shall be entitled to claim conformance with this Standard if
6、 ail the recordings that it makes on a tape meet the mandatory requirements of this Standard. A chim of conformance shall state whether or not one, or more, registered algorithms are implemented and, if so, the registered number) of all implemented algorithm(s). 2.3 Receiving system A system receivi
7、ng a magnetic tape cartridge for interchange shall be entitled to claim conformance with this Standard if it is able to handle any recording made on the tape according to this Standard. In particular it shall: a) be able to recognize the occurrence of extended blocks and to identify and retrieve dat
8、a from individual packets within the extended blocks; b) be able to recognize that the data has been processed, to identify the aigorithm(s) used, and to indicate to the host if it cannot restore the data to its original form: c) be capable of restoring to its original form data which has been proce
9、ssed according to zero or more registered algorithms. A claim of conformance shall state whether or not one, or more, registered algorithm(s) is (are) implemented and, if so, the registered number) of all implemented algorithms. 3 References ECMA-13 (1985) ECMA-120 (1993) IS0 683-131986 IS0 1302:199
10、2 ISO/lEC 11576 1993 File Structure and Labelling of Magnetic Tapes for Information Interchange Data Interchange on 12.7 mm %Track Magnetic Tape Cartridges Heat-treatable steels, alloy steels and free-cutting steels - Part 13: Wrought stainless steels Technical drawing - Method for indicating surfac
11、e texture on technical drawings Information technology - Procedure for the registration of algorithms for the lossless compression of data 4 Definitions For the purposes of this Standard, the following definitions apply. 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.9.1 4.9.2 4.9.3 4.9.4 4.10 algorithm A se
12、t of rules for transforming the logical representation of data. Average Signal Amplitude The average peak-to- value of the signai output of the read head measured over a minimum length of kick of 25,4 mm exclusive of missing pulses. back surface The surface of the tape opposite the magnetic coating
13、used to record dah Beginning of Tape (BOT) The point along the length of the magnetic tape indicated by the stat of the Density Identification Burst. byte An ordered set of eight bits acted upon as a unit. cartridge A container holding a supply reel of magnetic tape with an attached leader block. Cy
14、clic Redundancy Check Character A character represented by two bytes, placed at the end of a byte string and used for error detection. Data Block The data entity resulting from concatenating one or more Packets, and appending control information. Data Records Processed Data Record (PDR) The data ent
15、ity resulting from the application of an algorithm to a Logical Data Record. Host Data Record The uc of circle. Out-of-phne distortions Ail visd evidence of out-of-plane distortion shall be removed when the tape is subjected to a uniform tension of 0,6 N. Out-of-plane distortions are local deformati
16、ons which cause portions of the tripe to deviate from the plane of the surface of the tape. Out-of-plane distortions are most readily observed when the tape is lying on a flat surface under no tension. Cupping The departure across the width of tape from ;I flat surface shall not exceed 0.3 mm. PrOCe
17、dUR Cut a 1,O m f 0.1 m length of tape. Condition it for a minimum of 3 hours in the test environment by hanging it so that the coated surface is freely exposed to the test environment. From the centre portion of the conditioned tape cut a test piece of 25 mm length. Stand the test piece on its end
18、in a cylinder which is at least 25 mm high with an inside diameter of 13.0 mm f 0.2 mm. With the cylinder standing on an optical comparator measure the cupping by aligning the edges of the test piece to the reticle and determining the distance from the aligned edges to the corresponding surface of t
19、he test piece ;It its centre. Dynamic frictional characteristics In the tests of 7.10.1 and 7.10.2 the specified forces of 1,0 N and 130 N, respectively, comprise both the force component of the dynamic friction and the force of 0,64 N applied to the test piece of tape. NOTE 4 STD-ECMA ECMA-252-ENGL
20、 2993 3404593 0032974 298 -7- 7.10.1 Frictional drag between the recording surface and the tape back surface The force required to move the recording surface in relation to the back surface shall not be less than 1.0 N. Procedure a) b) c) d) Frictional drag between the tape recording surface and fer
21、rite after environmental cyclhg The force required to move the tape at a point 1,34 m from the leader block of the cartridge shall not be greater than 1,50 N. The force required at a point 4,3 m from the junction of the tape with the cartridge hub shall not exceed the first force by more than a fact
22、or of 4. Procedure Wrap a test piece of tape around a 25,4 mm diameter circular mandrel with the back surface of the test piece facing outwards. Place a second test piece of tape, with the recording surface facing inwards, around the fit test piece for a total wrap angle of 90“. Apply a force of 0.6
23、4 N to one end of the outer test piece of tape. Secure its other end to a force gauge which is mounted on a motorized linear slide. Drive the slide at a speed of 1 mmh. 7.10.2 Wind tape on to a spool hub of diameter 50 mm to an outside diameter of 97 mm with a winding tension of 2.2 N f 02 N. Repeat
24、 the following two steps five times: 1) 2) Acclimatize the tape for 48 hours at a temperature of 30.5 “C and a relative humidity of 85 %. The tape shall remain in this environment for steps d) and e). Apply a force of O, N to one end of a test piece of not more than 1 m, taken 1,34 m from the leader
25、 block. Pass the test piece over a femte rod of diameter 254 mm with the recording surface in contact with the rod for a total wrap angle of 90“. The rod shall be made from the femte specified in annex C. It shall be polished to a roughness value R, of 0,05 pm (roughness grade N2, IS0 1302). Pull th
26、e other end of the test piece horizontally at 1 mmh. Repeat step d) for a similar test piece taken 4,3 m from the junction of the tape with the cartridge hub. Store for 48 hours at a temperature of 50 “C and a relative humidity of 10 % to 20 %. Acclimatize in the testing environment for two hours an
27、d rewind with a tension of 2,2 N i 0,2 N. 7.11 Coating adhesion The force required to peel any part of the coating from the tape base material shali not be less than 13 N. Procedure a) b) c) Take a test piece of the tape approximately 380 mm long and scribe a line through the recording coating acros
28、s the width of the tape 125 mm from one end. Using a double-sided pressure sensitive tape, attach the full width of the test piece to a smooth metal plate, with the recording surface facing the plate, as shown in the figure below. Fold the test piece over 180“, attach the metal pinte and the free en
29、d of the test piece to the jaws of a universal testing machine and set the speed of the jaw separation to 254 mm per min. Note the force at which any part of the coating first separates from the base material. If this is less than 1,5 N, the test has failed. If the test piece peels away from the dou
30、ble-sided pressure sensitive tape before the force exceeds 15 N. an alternative type of double-sided pressure sensitive tape shall be used. If the back surface of the tape is coated, repeat a) to d) for the back coating. d) e) STD-ECMA ECMA-152-ENGL I1993 3404593 0032975 124 = -8- Recording surf ace
31、 Scribed line I - I I I I L1J U Press ur e -sensitive tape 7.12 Flexural rigidity The flexural rigidity of the tape in the longitudinal direction shall be between 0,M N-mm2 and 0,16 N.mm2. Procedure Clamp a 180 mm test piece of tape in a universal testing machine, allowing a 100 mm separation betwee
32、n the machine jaws. Set the jaw separation speed at 5 mm per minute. Plot force against distance. Calculate the flexural rigidiy using the slope of the curve between 2.2 N and 6,7 N. The calculation is : GFIWT 6LIL E= I=wT3/12 Flexural rigidity = 1 where : 6F T W 6ur. = change in length of the test
33、piece between the jaws divided by the onginal length between the jaws. = change in force in N = measured thickness in mm = measured width in mm 7.13 Electrical resistance of coated surfaces The electrical resistance of any square area of the recording surface shall be within the range: - - The elect
34、rical resistance of my backcoating shall be less than lo6 fi. ProCedure Condition a test piece of tape to the test environment for 24 hours. Position the test piece over two %-carat gold-plated, semi-circular electrodes having a radius r = 25.4 mm and a finish of at least N4, so that the recording s
35、urface is in contact with each electrode. These electrodes shdl be placed parallel to the ground and parallel to each other at a distance d = 12.7 mm between their centres. Apply a force F of 1.62 N to each end of the test piece. Apply a d.c. voltage of 500 V f 10 V across the electrodes and measure
36、 the resulting current flow. From this value, determine the electrical resistance. id C to 5 x lo8 R for non-backcoated tapes, id R to 5 x lo9 R for backcoated tapes. STD-ECMA ECMA-152-ENGL 1993 3404593 0032776 Ob0 H -9- Repeat for a total of 5 positions along the test piece and average the 5 resist
37、ance readings. For back-coated tape repeat the procedure with the backcoating in contact with the electrodes. F F When mounting the test piece, make sure that no conducting paths exist between the electrodes except that through the coating under test. NOTE 5 Particular attention should be given to k
38、eeping the surfoces clean. 7.14 Tape durability This Standard does not specify puameters for assessing tape durability. However, a recommended procedure is described in annex D. 7.15 Inhibitor tape This Standard does not specify parameters for assessing whether or not a tape is an inhibitor tape. Ho
39、wever, annex B gives further information on inhibitor tapes. 7.16 Tape abrasivity Tape abmivity is the tendency of the tape to wear the tape transport. The length of the wear pattern on a wear bar shail not exceed 56 pm when measured as specified in annex C. 7.17 he-recording condition Prior to reco
40、rding data, or to testing, the tape shall have been erased utilizing alternating magnetic fields of decaying levels (anhysteretic process) to ensure that the remanent magnetic moment of the recording surface does not exceed 20 % of the maximum remanent magnetic moment. Annex E specifies the method o
41、f measurement. In addition no low density transitions shall be present on the tape. 7.18 Magnetic recording characteristics The magnetic recording characteristics shali be as defined by the testing requirements given below. When performing these tests, the output or resultant signai shall be measure
42、d on the same relative pass for both a tape calibrated to the Master Standard Reference Tape and the tape under test (read-while-write or first forward- read-pass) on the same equipment. The following conditions shail apply to the testing of all magnetic recording characteristics, unless otherwise n
43、oted. - tape condition - bpespeed : pre-recording condition : not greater than 2,5 m/s STD=ECMA ECMA-LSZ-ENGL I1993 3q04593 0032977 TT7 - 10- 7.18.1 7.18.2 7.18.3 7.18.4 - uidyd Reference Tape. Traceability to the overwrite of the Master Standard Reference Tripe is provided by the calibration factor
44、s supplied with each Secondary Standard Reference Tape. 7.18.4.2 Procedure A tone pattern shaii be recorded which shall be the following sequence of flux transitions. 1 O O O O O 1 O O O O O where: al = 1,029 pm a2 = OS 14 pm A 972 ftpmm signal is then recorded over the tone pattern. Measure the Ave
45、rage Signal Amplitude of the residual of the fundamental frequency of the tone pattern (one sixth of the equency of the 972 ftpmm signal) and the Avenge Signal Amplitude of the 972 ftpmm signal. Both amplitude measurements should be made using suitable filters. 7.18.5 Narrow-Band Signal-to-Noise Rat
46、io (NB-SNR) The Narrow-Band Signal-tis follows (see &o 8.10) 130 = 3.30 mm f 0.25 mm I31 = 18.40 mm f 0,25 mm 6 = 1,50mm &0,25 mm r7 = 130 mm f 0,25 mm The oblique edge of the case shdl be tangential to the arc of circle defined by 6 at an angle A =40f30 8.9 Other external dimensions of the case (fi
47、gure 6) The external form of the case shall be further specified by I, = 113,2 mm f 0.3 rnm I, = 26,OO mm f 0,25 mm STDmECflA ECNA-152-ENGL 1993 3404593 0032982 3b4 - 15 - r8 = 14530 mm f 0,25 mm r9 = 14550 mm f 0,25 mm 6 =30f30 8.10 Central window (figure 5) The bottom side of the case shall have a
48、 central window. The location of its centre shall be specified by I, and lu = 61.00 mm f 0,25 mm Its diameter shall be d,=43,5 mm + 2.0 m - 1,omm The angle with its apex at the centre of this window and formed by the two lines tangential to the parts shown in figure 5 in cross-section shall be e = i
49、6of 30 8.11 Stacking ribs (figures 4 and 5) The bottom side of the case shall have two parallel stacking ribs. Their dimensions shall be I, = 5.00 mm i 0.25 mm I, = 1.00 mm f 0,16 mm l, = 7430 mm f 0,25 mm Their locations shall be defined by Z, = 31.00 mm f 0.25 mm l, = 7,50 mm i 0,32 mm l, = 79.50 rnrn i 0,25 mm 8.12 Flexibility of the case The flexibility of the top and bottom sides of the case (see figure 1) is the amount of deflection observed when they are submitted to a perpendicular force F. 8.12.1 Requirements The amount of deflec
