1、3404583 OOLL39 5LL EUROPEAN STANDARD EUROPISCHE NORM NORME EUROPENNE EN 61120-2 October 1993 UDC 621.396.7 : 681.84.083.84 : 681.327.636 Descriptors: Audio recording, digital recording, magnetic tape, data converter, code, format, recording characteristics, recording track English version Digital au
2、dio tape recorder reel to reel system, using 6)3 mm magnetic tape, for professional use Part 2: Format A (IEC 1120-2 : 1991) Systme denregistrement bande audionumrique, bobine bobine, utilisant une bande magntique de 6,3 mm, usage professionnel %il 2: Format A Digitales nnbandgert Spulensystem mit M
3、agnetband 6,3 mm fr Studioanwendungen Partie 2: Format A (CE1 1120-2 : 1991) (IEC 1120-2 : 1991) This European Standard was approved by CENELEC on 1993-09-22. CENELEC members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard
4、 the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French,
5、 German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Den
6、mark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotec
7、hnische Normung Central Secretariat: rue de Stassart 35, B- 1050 Brussels O 1993 Copyright reserved to CENELEC members Ref. No. EN 61120-2 : 1993 E = 3404583 OOLL40 233 Page 2 EN 61120-2 : 1993 Foreword The CENELEC questionnaire procedure, performed for finding out whether or not the International S
8、tandard IEC 1120-2 : 1991 could be accepted without textual changes, has shown that no common modifications were necessary for the acceptance as a European Standard. The reference document was submitted to the CENELEC members for formal vote and was approved by CENELEC as EN 61120-2 on 22 September
9、1993. The following dates were fixed: - latest date of publication . of an identical national standard (dop) 1994-09-01 - latest date of withdrawal of conflicting national standards (dow) 1994-09-01 For products which have complied with the relevant national standard before 1994-09-01, as shown by t
10、he manufacturer or by a certification body, this previous standard may continue to apply for production until 1999-09-01. Annexes designated normative are part of the body of the standard. In this standard, annex ZA is normative. 3404583 009LL41 17T Page 3 EN 61120-2 : 1993 CONTENTS 1 Main hck recor
11、ding . 1.1 1.2 1.3 1.4 1.5 Recording modulation method Signai Mock structure . 1.2.1 The Word fmat 1.2.2 The block structure . 1.2.3 SynchronizatEon pattern . Signai word distribution to tracks Error protection method . 1.4.1 The error correction code 1.4.1.1 C2Encoder 1.4.1.2 C1 der 1.4.2 Interleav
12、e sequen . Recording and reproducing characteristics . 1.5.1 Reference tape 1.5.2 Calibration tapes . 1.5.3 Procedure for adjusting recording current level and waveform 1.5.4 Spedficaons of tolerance relative to calibration tape . 2 Sub-track recording . 2.1 Digital recording method . Recording meth
13、od on sub-track 2 2.1.1 2.2 Alignment of digital audio signals and sub-track signals . 2.2.1 Alignment of cue audio-1 and cu8 audio-2 trade signal . 22.2 Alignment of time code iracl( signai . 3 Control word . 3.1 Control word configuration 3.2 Control data assignment 3.3 Block address . 3.4 C3 Enco
14、der 4 4 5 5 5 6 6 6 7 9 10 18 18 18 18 9 18 18 18 18 18 18 19 19 19 19 21 21 Annex ZA (normative) Other international publications quoted in this standard with the references of the relevant European publications 22 3404583 OOLL42 OOb W O0 O0 00 O0 Page 4 EN 61120-2 : 1993 O000 o001 O000 o1 O0 DIGIT
15、AL AUDIO TAPE RECORDER REEL TO REEL SYSTEM, USING 6,3 mm MAGNETIC TAPE, FOR PROFESSIONAL USE Part 2: Format A Electrical requirements for recording and reproducing equipment. 1 Main track recording 1.1 Recording modulation method In this subclause a method is first defined to convert binary data seq
16、uence of each of the 8 main digital tracks for recording on the magnetic tape. The second item described In 1.2.3, Is the definition of the synchronization pattern in recording code. The converted code is given by NRZI. The 2/4 M system is defined by dividing a binary data sequence into two-bit data
17、 segments and converting these into four-cell codes using the data of the four bits preceding and the four bits succeeding the two-bit data segment. The system uses the collected data to convert the two-bit data segments into four-cell codes ensuring that no less than two and no more than seven code
18、 cells “O“ exist between any code cells “1“ in a sequence of converted code. The conversion rule is given by the following table. 2i4 M conversion table “ O000 O100 YO0 1 Contents Unconditional E2 E, “10“ and 1, = OO “E, E,“ = 1 O and Il 4. I 00“ .E, E,“ = =io=, “L, L2“ I lo and I, L; = DO E, E, # 1
19、 O, “L, L; = 1 O and “I, L, = 00“ Except the foregoing E, c +-io-, WE ,9 = -109 and .L, 4 901 E, lo“, “E, E,“ I “10“ and .L, L,“ e D1 E, Es = lo and “E, E, = “10“ Except the foregoing where: E, = data bits preceded by n-bit. to 2-bit data to be conveited in original data sequence L, I data bits succ
20、eded by n-bit, to 2-bit data to be converted in original data sequence Y complement logic of logical sum of two cells immediately before code bit Y in the converted code sequence The converted code is given by N RZI. Page 5 EN 61120-2 : 1993 SYNC CTRLW or C3 PCM DATA or C2 CHECK 1.2 Signal block str
21、ucture 1.2.1 The word format - Main C1 (CRC) track The word slots to be recorded on the main tracks have 20 bits at speed I and 16 bits at speed II. PCM samples are specified as uniformly quantified and are represented in the form of sign bit (MSB) leading. 1.2.2 The block structure The following fi
22、gure shows the data configuration and the contents of frames and blocks. I+ t +I 4. 1 SYNC SYNC SYNC SYNC SYNC SYNC SYNC SYNC C3 CHECK C3 CHECK BA BA ID ID C3 CHECK C3 CHECK C2 CHECK PCM DATA PCM DATA PCM DATA PCM DATA PCM DATA PCM DATA C2 CHECK C1 (CRC) C1 (CRC) C1 (CRC) C1 (CRC) C1 (CRC) C1 (CRC)
23、C1 (CRC) C1 (CRC) Track 8 Track 7 Track 6 Track 5 Track 4 Track 3 Track 2 Track 1 Block configurat-ion Legend: BA P Blocaddress ID = Identification data Frame and block parameters: . SYNC length . p = 16 bits . Control word or C3 length . cw = 8 bits . Data or C2 length . d = 320 bits . C1 (CRC) len
24、gth . C = 16 blts . Frame length . f = 360 bits . Block configuration . b I 8 frames W 3404583 0091L44 989 Page 6 EN 61120-2 : 1993 1.2.3 Synchronization pattern The synchronization pattern in recording code consists of 32 cells, in which the magnetira- tion reversion interval is confined within the
25、 rule of 2i4 M scheme, so as to protect the overwrite characteristics from deterioration, and a pattern of lower cross correlation functlon is chosen so as to let the probability of erroneous SYNC detection be reduced at the vicinity of SYNC signal. The synchronization pattern is represented in NRZI
26、, and given as follows. - O01 O0001 O001 00001 O01 O01 O001 O0000 + recording direction + 1.3 Signai word distribution to tracks Input PCM samples of two audio channels are allocated for six tracks by a Matrix device and additionally two tracks of C2-check data are encoded in the way described in th
27、e following figure: 1.4 Error protection method Error protection method is two dimensional. Error detection is made possible by the CRC check word recorded for each frame of each track, and by the Reed-Solomon code. Error correction is made possibly by the Reed-Solomon code with the aid of CRC check
28、 results. 3909583 0091145 815 Page 7 EN 61120-2 : 1993 1.4.1 The error correction code The error correction code referred to as the RSC code shall be used. The RSC code is a sub-class of the generalized product code. The code is constructed by the (16.12.5) Reed- Solomon code over GF ), as code C2,
29、and by the (344,328,4) CRC over GF(2), as code C1. Symbol interleaving has been performed between C2 encoding and C1 encoding. Generator polynomials for code C2, and code C1 are given by the following equations: C1: G, (x) P xl + xl + xs + 1 3 C2: O, (x) 5 a (x - a) imo G, (x) is the generator polyn
30、ominal based on CCITT V41 recommended 16-bit Cyclic Redundancy Check (CRC) word: a is the primitive element of GF (2). The vector representation of a is a=(O O O O O O 1 O) a7a6a5 a a a a a 43210 and the primitive polynomial g(x) is 32 g(x)Pxa+x4+x +x +1 All elements are shown in the following table
31、: Page 8 EN 61120-2 : 1993 Number Element o 00000001 1 00000010 2 00000100 3 00001000 4 00010000 5 00100000 6 01000000 7 10000000 8 00011101 9 00111010 10 01110100 11 11101000 12 11001101 13 10000111 14 00010011 15 00100110 16 01001100 17 10011000 18 00101101 19 01011010 20 10110100 21 01110101 22 1
32、1101010 23 11001001 24 10001111 25 00000011 26 00000110 27 00001100 28 00011000 29 00110000 30 01100000 31 11000000 32 10011101 33 00100111 34 01001110 35 10011100 36 -00100101 37 01001010 38 10010100 39 00110101 40 01101010 41 11010100 42 10110101 43 01110111 44 11101110 4s 11000001 46 10011111 47
33、00100011 48 01000110 49 10001100 50 00000101 51 00001010 52 00010100 53 00101000 54 01010000 55 10100000 56 01011101 57 10111010 58 01101001 59 11010010 60 10111001 61 01101111 62 11011110 63 10100001 THE ELEMENT OVER GF (2) Number Element 64 01011111 65 10111110 66 01100001 67 11000010 68 10011001
34、69 O0101111 70 01011110 71 10111100 72 O1100101 73 11001010 74 10001001 75 00001111 76 00011110 77 00111100 78 01111000 79 11110000 80 11111101 81 11100111 82 11010011 83 10111011 84 01101011 85 11010110 86 10110001 87 01111111 88 11111110 89 11100001 90 11011111 91 10100011 92 O1011011 93 10110110
35、94 01110001 95 11100010 96 11011001 97 10101111 98 01000011 99 10000110 100 00010001 101 00100010 102 01000100 103 10001000 104 O0061101 105 00011010 106 O0110100 107 01101000 108 11010000 109 10111101 110 01100111 111 11001110 112 10000001 113 O0011111 114 00111110 115 01111100 116 11111000 117 111
36、01101 118 11000111 119 10010011 120 00111011 121 01110110 122 11191100 123 11000101 124 10010111 125 00110011 126 01100110 127 11001100 Number Element 128 10000101 129 00010111 130 00101110 131 010111100 132 10111000 133 01101101 134 11011010 135 10101001 136 01001111 137 10011110 138 00100001 139 0
37、1000010 140 10000100 141 O0010101 142 00101010 143 01010100 144 10101000 145 01001101 146 10011010 147 O0101001 148 O1010010 149 10100100 150 O1010101 151 10101010 152 O1001001 153 10010010 154 00111001 155 O1110010 156 11100100 157 11010101 158 10110111 159 O1110011 160 11100110 161 11010001 162 10
38、111111 163 O1100011 164 11000110 165 10010001 166 00111111 167 O1111110 168 11111100 169 11100101 170 11010111 171 10110011 172 01111011 173 11110110 174 11110001 175 11111111 176 11100011 177 11011011 178 10101011 179 01001011 180 10010110 181 00110001 182 01100010 183 11000100 184 10010101 185 001
39、10111 186 01101110 187 11011100 188 10100101 189 01010111 190 10101110 191 01000001 Number Element 192 10000010 193 00011001 194 00110010 195 01100100 196 11001000 197 10001101 198 00000111 199 00001110 200 00011100 201 00111000 202 01110000 203 11100000 204 11011101 205 10100111 206 O1010011 207 10
40、100110 208 01010001 209 10100010 210 01011001 211 10110010 212 01111001 213 11110010 214 11111001 215 11101111 216 11000011 217 10011011 218 00101011 219 O1010110 220 10101100 221 01000101 222 10001010 223 O0001001 224 00010010 225 O0100100 226 01001000 227 10010000 228 00111101 229 01111010 230 111
41、10100 231 11110101 232 11110111 233 11110011 234 11111011 235 11101011 236 11001011 237 10001011 238 00001011 239 00010110 240 00101100 241 01011000 242 10110000 243 01111101 244 11111010 245 11101001 246 11001111 247 10000011 248 00011011 249 00110110 250 01101100 251 11011000 252 10101101 253 0100
42、0111 254 10001110 255 00000001 3404583 0091147 b98 Page 9 EN 61120-2 : 1993 1.4.1.1 C2 Encoder The C2 check code shall be calculated so as to meet the following equation: H2 x V2 O where: V2 is encoded data consisting of input data stream and C2 check symbols, and H, is the parity check matrix which
43、 is to be given as follows: 1 11 l-1 v2 = 1 wl - 12d w2 w4 w3 - 12dl 1 WS - 12d w6 w7 - 12d w0 w9 - 12d 1 1 Wl o 1 wll - 12d . a15 a14 al a30 a2 1 . H2 = 42 a . (1 st symbol) (1 st symbol) (1 st symbol) (1 st symbol) (1st symbol) (1 st symbol) (1st symbol) (1st symbol) (1st symbol) (1 st symbol) (1s
44、t symbol) (1st symbol) c3 (1st symbol) c2 (1st symbol) Cl (1 s t symbol) Co (1st symbol) 1.4.1.2 CI encoder . a3 1 Input data symbols C2 check symbols The C1 code is a code over the Qalols Field GF (2), the C1 check code being referred to as CRC (Cyclic Redundancy Check) code, which is to be calcula
45、ted by the following formula: 3404583 0093348 524 Page 10 EN 61120-2 : 1993 “ I- a O 1 - - - 8 8 E E E E P a b 2 O O n P I K m P 3i 3404583 009LL49 460 Page 11 EN 61120-2 : 1993 C1 check code (1 + b,) x343 + (1 +b2) xS2 + + (1 + b16) x 328 x327 + b x326 + - + b328 xi6 Mod G, (x) + b17 18 where G, (x
46、) = x16 + x12 + xs + 1 Vl - bl b2 b16 b17 b18 - b328 1.4.2 Interleave sequence 1) Symbol and word structure The quantized two channel signals are restructured into 8 bits symbols and into a word structure comprising 2 x 20 = 40 bits for speed I and 2 x 16 = 32 bits for speed il. Figures 1 and 2 illu
47、strate this symbol and word structure for the two speeds. The symbol stands for a Galois field index composed of 8 bits, which is used for C2 code. 2) Interleave sequence Figure 3 shows the C2 encoder and interleave sequence: the values of d, d2, and d3, are given in the table below. Delay quantity
48、(unit I words) In Figures 4 and 5 examples of data arrangement in case of digital audio track (8 tracks) are given. In Figures 6 and 7 the data interleave diagram on the tape for each mode Is shown. Page 12 EN 61120-2 : 1993 m 3404583 OOL150 LB2 = t - O n E n ? (Y O n E m f Page 13 EN 61120-2 : 1993
49、 ,amtrn(t- F n Q2 W VJ + (Y W n m W A t + + 01 o + r 0 c I F r + (Y W + 01 U A VJ W f- + + + m 8 c 4 I (Y z N I (o F (Y I OD r (Y I c 7 I N F I m r I t t I t I t I I + + + + + + + + + + + m (Y- o I II I I l I I I I I II I II 1 l I I I I I I I !I II I I I I I I I I I1 I I I I I I I I I I 1 I I I l I I I I I I I 8 II I I I I I II I II II I I I II I1 I l If I II II II I I I I II II II Il II I II II I I I I II I I VJ (Yr o I I I Il I I I II I I I I II I II II II I I I I I I I I I I I I I + + I I
