1、ECMA E U R O PEAN CO MPUTER HAN U PACTU RE RS ASS OC1 ATION STANDARD ECMA-147 DATA INTERCHANGE ON 90mm FLEXIBLE DISK CARTRIDGES USING MFM RECORDING AT 31831 ftprad ON 80 TRACKS ON EACH SIDE - IS0 TYPE 303 - December 1990 ECMA*L47 90 3404593 0002626 9 W - BRIEF HISTORY Technical Committee TC19 of ECM
2、A began work on the standardization of flexible disk cartridges in 1974. As a result ECMA has produced a set of standards for different types of flexible disk cartridges (FDC): 200 mm FDCs 130 mm FDCs 90 mm FDCs ECMA-58 ECMA-59 ECM A-69 ECMA-66 ECMA-70 ECMA-78 ECMA-99 ECMA- 1 O0 ECMA- 125 Standards
3、ECMA-70, ECMA-78 and ECMA-99 specify two different track formats. The first specifies FM recording in Cylinder O0 and is intended for use with the labelling system specified in Standard ECMA-91. The second track format, which is identical with that of Standard ECMA-100, specifies MFM recording on al
4、l cylinders and is intended for use with the volume and file structure of Standard ECMA-107. Standard ECMA-100 was developed with a view to achieving a capacity of I Mbyte. Standard ECMA-125 is a further development of the same medium providing a capacity of 2 Mbytes. The present ECMA Standard is st
5、ill a further development of FDCs of 90 mm, but with a magnetic layer of barium ferrite allowing for a higher recording density. This medium provides an unformatied capacity of 4 Mbytes. Upon request of Committee ISO/lEC/JTC1/SCI 1, this ECMA Standard has been contributed to ISOIIEC for adoption und
6、er the fast-track procedure. This Standard has been accepted by the General Assembly of ECMA on 13th December 1990. , ECMA ECMAUL47 90 3404593 0002b27 O -i- TABLE OF CONTEN“S SECTION1 - GENERAL 1. SCOPE AND CONFORMANCE 1.1 Scope 1.2 Conformance 2. REFERENCES 3. DEFINITIONS 3.1 3.2 3.3 3.4 3.5 3.6 3.
7、7 3.8 3.9 3.10 3.1 1 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 3.2 1 3.22 Average Signal Amplitude Case Direction of Rotation Eraseability Formatting Hub In-Contact Index Initialization Line of Access Liner Master Standard Reference Flexible Disk Cartridge Recording Disk Reference Erase Field Ref
8、erence Field Secondary Standard Reference Flexible Disk Cartridge Shutter Side Standard Reference Amplitude Test Erase Current Test Recording Current Typical Field 4. GENERAL DESCRIPTION 4.1 Drawings 4.2 Main Elements 4.3 Description SECTION II - ENVIRONMENTS, MECHANICAL AND PHYSICAL CHARACTERISTICS
9、 5. GENERAL REQUIREMENTS Page 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 3 3 3 4 4 4 ECMA ECtlA*i147 90 H 3404593 0002b2B 2 W - ii - 6. 7. 5. I Environment and Transportation 5.1.1 Testing environment 5.1.2 Operating environment 5.1.3 Storage environment 5.1.4 Transportation 5.2 Materials 5.2.1 Case 5.2.2 Li
10、ner 5.2.3 Disk 5.2.4 Hub DIMENSIONAL CHARACTERISTICS 6. i Case 6.1.1 6. i .2 6.1.3 6.1.4 6.1.5 6.1.6 6.1.7 6.1.8 6.1.9 6.1.10 Shape (Fig. 7) Thick ness Hub access hole (Fig. 7) Locating holes (Fig. 7 and 9) Label area Head windows (Fig. 9) Write-inhibit hole (Fig. 8) Identification hole (Fig. 7 and
11、8) Profile of the shutter edge of the case (Fig. 7 and 9) Shutter (Fig. 8 and 9) 6.2 Liner 6.3 Disk (Fig. IO) 6.3.1 Diameter 6.3.2 Thickness 6.4 Hub (Fig. 10) 6.4.1 Dimensions 6.4.2 Optional Handling Notches (Fig. 7 and 8) Interface between Cartridge and Drive Hub orientation holes (Fig. 10) 6.5 6.6
12、 6.7 Compliance PHYSICAL CHARACTERISTICS 7.1 Flammability 7.2 7.3 7.4 Torque Coefficient of Linear Thermal Expansion of the Disk Coefficient of Linear Hygroscopic Expansion of the Disk 7.4.1 Starting torque 7.4.2 Running torque without heads loaded 4 4 4 4 5 5 5 5 5 5 5 5 5 6 6 6 7 7 7 8 8 9 9 9 9 9
13、 9 9 IO IO II 11 11 11 11 11 11 11 11 SECTION III - UNRECORDED FLEXIBLE DISK CARTRIDGE 12 8. MAGNETIC CHARACTERISTICS 12 8.1 Recording Area 8.2 Track Geometry 8.3 8.2.1 Number of tracks 8.2.2 Width of tracks 8.2.3 Track location 8.2.4 Track number Functional Testing 8.3.1 Surface tests 8.3.2 Track q
14、uality tests 8.3.3 Rejection criterion SECTION IV - RECORDING METHOD AND TRACK FORMAT 9. GENERAL REQUIREMENTS 12 12 12 12 12 12 12 13 14 14 15 15 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8 9.9 9.10 9.1 I 9.12 9.13 Mode of Recording Track Location Tolerance of the Recorded Flexible Disk Cartridge Recording Offs
15、et Angle Density of Recording Flux Transition Spacing Average Signal Amplitude Byte Sector Cy1 i nder Cylinder Number Data Capacity of a Track Hexadecimal Notation Error Detection Characters (EDC) IO. TRACK LAYOUT 10.1 index Gap 10.2 Sector Identifier 10.2.1 Identifier Mark 10.2.2 Address Identifier
16、 10.3 Identifier Gap 10.4 Data Block 10.4.1 Data Mark 10.4.2 Data Field 10.4.3 EDC 10.5 Data Block Gap 10.6 Track Gap -=- ,i- -3 15 15 15 16 16 Ih 16 17 17 17 17 17 17 17 18 18 18 18 19 19 19 19 19 19 20 Y y- I _ I _ - ECMA ECMA*lY7 90 c3 3404593 O002630 O E - iv - 11. CODED REPRESENTATION OF DATA 1
17、1.1 Byte coding 11.2 Bit Coding APPENDIX A - TEST FOR COMPLIANCE APPENDIX B - MEASUREMENT OF LIGHT TRANSMIITANCE APPENDIX C - METHOD FOR MEASURING THE EFFECTIVE TRACK WIDTH APPENDIX D - PROCEDURE AND EQUIPMENT FOR MEASURING FLUX TRANSITION SPACING APPENDIX E - DATA SEPARATORS FOR DECODING MFM RECORD
18、ING APPENDIX F - EDC IMPLEMENTATION APPENDIX G - CARTRIDGE DISTORTION TEST GAUGE APPENDIX H - METHOD FOR MEASURING PEAK SHIFT APPENDIX J - HEAD AND READ AMPLIFIER FOR FUNCTIONAL TESTING 20 20 20 31 33 37 39 41 43 45 47 51 APPENDIX K - PROCEDURE FOR DETERMINING TEST RECORDING CURRENT AND TEST ERASE C
19、URRENT 53 ECMA ECMA*IJ47 90 6 3404593 0002b31 - i -1- SECTION1 - GENERAL 1. SCOPE AND CONFORMANCE 1.1 scope This ECMA Standard specifies the characteristics of 90 mm flexible disk cartridges recorded at 31831 ftprad using modified frequency modulation recording, on 80 tracks on each side. Such flexi
20、ble disk cartridges are identified as IS0 Type 303. It specifies the mechanical, physical and magnetic characteristics of the cartridge, so as to provide physical interchangeability between data processing systems. It also specifies the method of recording, the quality of the recorded signais, the t
21、rack layout and the track format. Together with Standard ECMA-107, this Standard provides for full data interchange between data processing systems. 1.2 Conformance A 90 mm flexible disk cartridge is in conformance with this Standard if it meets all mandatory requirements specified herein. 2. REFERE
22、NCES ECMA-107 : Volume and File Structure of Flexible Disk Cartridges for Information Interchange 1SO 6831 i 3 IS0 9983 : Wrought Stainless Steels : Information processing systems - Designation of unrecorded flexible disk cartridges. 3. DEFINITIONS For the purpose of this Standard the following defi
23、nitions apply. 3.1 Average Signal Amplitude The Average Signal Amplitude for a track is the arithmetically averaged value of the output voltages measured peak-to-peak over the whole track. 3.2 CaSe A protective enclosure including a shutter mechanism, an identification hole and a write-inhibit hole.
24、 3.3 Direction of Rotation The direction of rotation shall be counter-clockwise when looking at Side O. 3.4 Eraseability The eraseability is the ratio (percentage) of the residual Average Signal Amplitude, after erasing the original signal, to the original Average Signal Amplitude on the specified t
25、rack and at the specified flux transition density. 3.5 Formatting Writing the proper control information establishing the physical cylinders and the addresses of physical records on the surfaces of the flexible disk. 3.6 3.7 3.8 3.9 3.10 3.1 1 3.12 3.13 3.14 3.15 -2- Hub A centring and referencing d
26、evice attached to the disk which allows torque to be transmitted to the disk. The hub is attached to the centre of the disk. it ensures centring of the disk on the drive shaft in a unique angular position. In -Con tact An operating condition in which the magnetic surface of the disk is in physical c
27、ontact with the magnetic heads. Index The signal generated in the index transducer of the drive by the drive spindle once per revolution. Initialization Writing any information initially required lo be on the flexible disk cartridge, e.g. the Volume Label, prior to the commencement of general proces
28、sing use. Line of Access The straight line described by the centre of the gap of the read/write head as it is positioned from Track O0 to Track 79. Liner Suitable material positioned between the case and the disk to provide cleaning action and protection from abrasion. Master Standard Reference Flex
29、ible Disk Cartridge A reference flexible disk cartridge selected as the standard for reference fields, signal amplitudes, resolution, peak shift, and reference erase field. Track O0 and Track 79 on both sides are declared as reference tracks. The reference tracks are calibrated at 300 rpm. NOTE i Th
30、U Master Standar will be established by the Physikalisch-Technische Bundcsansralt I PTBI, Bundesallee 100, 0-3300 Braunsch weig, Germany. The Master Standard established by Toshiba Corporalion shall be used uniil the PTB Master Standard established. Recording Disk A flexible disk which accepts and r
31、etains, on the specified side or sides, magnetic signals intended for inputloutput and storage purposes. Reference Erase Field The Reference Erase Field is the DC field which causes an eraseability of 5 % when measured for the Master Standard Reference Flexible Disk Cartridge. There are two Referenc
32、e Erase Fields, one for each side. Reference Field The Reference Field is the Typical Field of the Master Standard Reference Flexible Disk Cartridge. There are two Reference Fields, one for each side. 3.16 Secondary Standard Reference Flexible Disk Cartridge A flexible disk cartridge the performance
33、 of which is known and stated in relation to that of the Master Standard Reference Flexible Disk Cartridge. NOTE 2 Secondary Srandard Reference Flexible Disk Cartridges can be ordered from PTB, Lab. 1.41, under Part Number RM 10994 icnril the year 2001. it is intended that these be used for calibrah
34、g tertiary carlridges for use in routine calibration. Until they become available from PTB, Secondary Standard Reference FDCs can be ordered under part number TRD 301 from Toshiba Corporation, 1-1 Shibaura, i-chome, Minato-Ku, Tokyo 105. 3.17 Shutter A device which uncovers the head windows upon ins
35、ertion, and automatically covers them upon removal from the drive. 3.18 Side Side O is the side engaged by the spindle. Side 1 is the opposite side. 3.19 Standard Reference Amplitude The Standard Reference Amplitudes (SRAS) are the Average Signal Amplitudes derived from the reference tracks of the M
36、aster Standard Reference Flexible Disk Cartridge using the Test Recording Current. There are four SRAS, two for each side: SRA-If is the Average Signal Amplitude from a recording written using If at Track OO. SRA-2f is the Average Signal Amplitude from a recording written using 2f at Track 79. 3.20
37、Test Erase Current The erase current between 148 % and 152 % of the erase current which produces the Reference Erase Field at test Frequency If on track OO. 3.21 Test Recording Current The Test Recording Current is the current between 198% and 202% of the current which produces the Reference Field a
38、t 2f on Track 79. There are two Test Recording Currents, one for each side. 3.22 Typical Field The minimum recording field which, when applied to a flexible disk cartridge, causes an average signal amplitude equal to 95% of the maximum Average Signal Amplitude when taken as a function of the recordi
39、ng field at the specified track and flux transition density. 4. GENERAL DESCRIPTION 4.1 Drawings In the enclosed drawings an example of implementation of the flexible disk cartridge is shown schematically. 4.2 Main Elements The main elements of the flexible disk cartridge are: - the recording disk,
40、-4- - the liner, - the case. 4.3 Description The cartridge is of a substantially square form. It includes a central hole on one side, a head window on both sides, an identification hole and a write-inhibit hole. The liner is provided between the case and the disk. It comprises two layers of material
41、 between which the disk lies. The disk has a central hole with a metal hub attached. SECTION II - ENVIRONMENTS, MECHANICAL AND PHYSICAL CHARACTERISTICS 5. GENERAL REQUIREMENTS 5.1 Environment and Transportation 5.1.1 Testing environment Tests and measurements made on the cartridge to check the requi
42、rements of this Standard shall be carried out under the following conditions: Tem peratu re RH 40% to 60% : 23 “C f 2 “C Conditioning before testing : 24 hours minimum For the tests specified in 8.3 the temperature and the RH shall be measured in the air im- mediately surrounding the cartridge drive
43、. For all other tests the temperature and the RH shall be measured in the air immediately surrounding the cartridge. The stray magnetic field at any point on the disk surface, including that resulting from the concentrating effect of the recording head, shall not exceed 4000 Aim. 5.1.2 Operating env
44、ironment Cartridges used for data interchange shall be operated under the following conditions: Tem pe ra t u re RH : 20% to 80% Wet bulb temperature : 10 “C to 51,s “C : less than 29 “C The temperature and the RH shall be measured in the air immediately surrounding the cartridge. It is recommended
45、that the rate of change of the temperature should not exceed 20 “C per hour. It is also recommended that the temperature and the RH conditions when reading a cartridge are not at the opposite extremes to the conditions when it was recorded. There shall be no deposit of moisture on or in the cartridg
46、e. The stray magnetic field at any point on the disk surface, including that resulting from the concentrating effect of the recording head, shall not exceed 4000 Nm. 5.1.3 Storage environment During storage the cartridges shall be kept within the following conditions: Tem pera t u re : 4 “C to 53 OC
47、 Y. 5.1.4 5.2 5.2.1 5.2.2 5.2.3 5.2.4 RH : 8% to 90% The ambient stray magnetic field shall not exceed 4000 Alm. There shall be no deposit of moisture on or in the cartridge. NOTE 3 Cartridges which have been stored at temperatures and humidities exceeding the operating conditions may exhibit degrad
48、ed performance characteristics. Such cartridges should be sub- jecied to a conditioning period of not less than 24 hours within the operating environment prior to use. Transportation Responsibility for ensuring that adequate precautions are taken during the transportation shall be with the sender. T
49、he cartridge shall be in a protective package free from dust or extraneous matter. It is recommended that a sufficient space exists between cartridge and outer surface of the final container, so that risk of erasure due to stray magnetic fields will be negligible. It is recommended that the following conditions are not exceeded: Tem pera t u re : -40 “C to 60 “C Maximum rate of temperature change RH : 8% to 90% : 20 “C per hour There should be no deposit of moisture on or in the cartridge. Materials CaSe The case may be constructed from any suitable material su
