GB2342259A

GB2342259A - Apparatus for multilevel encoding and recording

Info

Publication number: GB2342259A
Application number: GB9821419A
Authority: GB
Inventors: Dan Dobre; Costica Dobre
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-10-01
Filing date: 1998-10-01
Publication date: 2000-04-05
Also published as: GB9821419D0

Abstract

Data in the form of eight bit ASCII characters are encoded into one or more multilevel signals for subsequent recording. Specifically, the eight bits may be recorded as four signals each having four possible values, or two signals each having 16 possible values, or one signal having 256 possible values. The recording medium may be a magnetic disk (eg a floppy disk or hard disk drive) or an optical disk (eg CD-ROM or DVD), and the various signal values may be represented by predetermined widths (W-W<SB>3</SB>) on the recording medium. The base conversion is achieved by division of the ASCII character in decimal form (see tables 1-3 at the end of the description).

Description

2342259 PATENTS ACT 1977 Agent's Ref.. P 12804G13-ALNnH "A data encoding

method and apparatus" THIS INVENTION relates to a data encoding method and apparatus. More 1 particularly, the invention relates to a method and apparatus for encoding data 'for storage on a data storage medium.

Methods and apparatus for the storage of data on a disk, be it a magnetic disk or a recordable optical disk, are well-known. However, these methods suffer from the disadvantage that each ASCII character contained in the data is stored as an eight bit binary number (e.g. 0 10 1110 1).

It is an object of the present invention to seek to provide a method and apparatus for encoding data for storage on a disk or other data storage medium Z by representing an ASCII character or the like contained in the data by less than eight bits by encoding using a so-called decimal bit number.

Accordingly, one aspect of the present invention provides a method of encoding data for recordal on a recording medium comprising the steps of.

C c converting the data into a byte having a number of bits, each bit having more than two possible values.

Another aspect of the present invention proVides an apparatus for encoding data on a recording medium comprising means to convert the data into a byte having a number of bits, each bit having more than two possible values.

1 In order that the present invention may be more readily understood, embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which:

0 Figure I is a schematic representation of a view, from above, of a conventional binary bit "0" and "I" stored on a magnetic disk, Fiallre 2 is a schematic representation of a view, from above, of analogue C bits "0", "1", "2", and "33" stored on a magnetic disk in accordance with an embodiment of the present invention, Figure 3 is a schematic representation of the view, from one end, of a conventional binary bit "0" and " I " stored on an optical disk-, Figure 4 is a schematic representation of a view, from one end, of Z_D analogue bits "1", "2" and "-')" stored on an optical disk in accordance with an embodiment of the present invention; Figure 5 is a schematic representation of the voltage levels which a 0 0 transducer head needs to switch between in order to store data in a conventional binary form on a magnetic disk; I Figure 6 is a schematic representation of the voltage levels which a transducer head needs to switch between in order to store data in accordance with an embodiment of the present invention on a magnetic disk; Figure 7 is a schematic representation of the power levels which a transducer head needs to switch between in order to store data in a conventional binary form on an optical disk; and 1 1 Figure 8 is a schematic representation of the power levels which a transducer head needs to switch between in order to store data in accordance with an embodiment of the present invention on an optical disk.

Referring to the Figures and, in particular, Figure 1, a binary bit, be it 0 either a "0" or a " 1 " occupies a predetermined area of, for example, a track on a magnetic disk. In the example shown in Figure 1, a binary "0" and a binary " 1 " both occupy a strip of track having a length L and a width W. Referring to Figure 5 in combination with Figure 1, a voltage level VI is used to indicate a binary bit "V and a voltage level VO is used to indicate a binary bit "0".

0 Typically, VO is in the order of 0 V and V I is in the order of 30 mV.

A transducer head is provided to fly over the magnetic disk surface. The transducer head is operable both to read data from the magnetic disk surface and to write data onto the magnetic disk surface. To write data onto the magnetic disk surface, the transducer head applies a voltage to the magnetic disk surface over which it is flying. To write a binary bit "0", voltage level VO is applied and to write a binary bit "I", voltage level V1 is applied. The areas shown in Figure 1 therefore have a residual magnetic field which is determined by the voltage levels applied thereto by the transducer head.

In order to read data from the macnietic disk surface, the transducer head flies over the magnetic disk surface and a voltage is induced in the transducer head by the residual magnetic field fi.om the magnetic surface below the transducer head. The amplitude of the voltage induced in the transducer head is proportional to the strength of the magnetic field of the portion of the magnetic disk surface below the transducer head. Typically, a comparator is provided to distinguish between the voltage levels induced in the transducer 3 head and decide whether the induced voltage is indicative of a binary bit "0" or a binary bit " 1 ".

Similarly, data can also be written to and read from an optical disk such as a CD-ROM or a DVD. An electro-optical transducer head is provided in the form of a laser source for writing data to the optical disk and an electro-optical 0 detector for reading data from the optical disk. Referring to Figure 3 in combination with Figure 7, Figure 3 shows a schematic representation of a side view of data written on an optical disk. Binary bits are represented by lands and pits on the surface of the optical disk. There is a height difference H between a land and a pit. A land may represent a binary bit "I" and a pit may represent a binary bit "0". The laser on the electro- optical transducer head can alter the texture of the surface of the optical disk to produce both lands and pits and the electro-optical detector on the transducer head can distinguish, from light reflected from the surface of the optical disk, whether that light has been reflected from a land or a pit so as to make a decision as to whether the reflected light is representative of a binary bit "0" or a binary bit "I". Other encoding methods which recognise the transition of a signal as a threshold is passed between a land and a pit are commonly used.

Put simplistically, to produce a pit in the optical disk surface, a power level P I is required whereas to produce a land requires a power level PO.

Any character to be represented as data on a disk surface is represented initially by a series of eight binary bits, an eight bit data stream. The conventional means of writing data to a disk surface and reading data therefrom therefore requires the data to be written as a series of eight binary bits "0" and I" which takes up a substantial amount of disk space and requires a substantial amount of time to write to or read from the disk surface.

4 0 The present invention is a method of and apparatus for storing data on a recording medium and reading data from a recording medium which can represent characters which would normally be represented by a series of eight binary bits by a byte comprising a series of less than eight bits and, in the particular example given below, by a series of four bits, each of the bits having more than two possible values.

In one example of the present invention, the data for an ASCII character to be written to a magnetic disk surface is first converted into a byte referred to as a so-called decimal four bit number. The conversion method is described below. In order to describe clearly this example of the present invention, Table 1 at the end of this description will be referred to. Table 1 has five columns: a decimal number; its binary equivalent; its hexadecimal equivalent; the ASCII equivalent; and the so- called decimal four bit number produced in accordance with an embodiment of the invention. Each of the 256 ASCII characters used by a computer are converted to a so-called decimal four bit number.

It is assumed that the skilled person is capable of converting from decimal, to binary, to hexadecimal and therebetween based on the ASCII character corresponding to a respective decimal, binary or hexadecimal number. Conversion from a decimal number to the decimal four bit number is carried out as follows. Firstly, the decimal equivalent of a character is divided by 4 and the remainder stored. The resultant quotient is also divided by 4 and that remainder stored. This process is repeated until the resultant quotient is zero in which case the previous quotient becomes the last remainder. A maximum of four remainders (rl, 1-2, 1-3, j- 4) are obtained and comprise the socalled decimal four bit number which is in the form of four adjacent bits r4r3r2i.l.

1 1 By way of example, the ASCII character "F" has a decimal equivalent of 70. To convert the decimal number 70 into the decimal four bit number, the above-described process is carried out:

The decimal number to be converted, 70, is divided by 4 to give a quotient q 1 of 17 and a remainder r 1 of 2; the quotient qI of 17 is divided by 4 to give a quotient q2 of 4 and a remainder r2 of 1; the quotient q2 of 4 is divided by 4 to give a quotient q_35 of 1 and a remainder r'-)' of 0; and the quotient Q3 of 1 is divided by 4 to give a quotient q4 of 0 and a remainder 1-4 of 1.

The remainders r 1, r2, r_33 and r4 make up the four bits of the decimal four bit number in the form r4r3r2i- 1 -- i.e. 10 12 in the present case.

To convert back to a decimal number fl-om the decimal four bit number, the following formula is used..

(4 3 r4) + (4 2 r3) + (41 r2) + (40 rl) At the end of the conversion process, the ASCII character 'F' is now represented by the decimal four bit number 1012. It is this decimal four bit number which is to the recorded on the disk surface.

In contrast to the conventional method and apparatus for recording data on a disk surface, the apparatus embodying the present invention uses a Z:) transducer head, for a magnetic disk, which is switchable between four voltage 6 levels, VO, V1, V2 and V3. The voltage level VO corresponds to substantially 0 Volts. Voltage levels V I, V2 and V3 are progressively higher voltage levels than VO, their being equal voltage increments between the respective voltage levels. Thus, for example, V1 might be in the order of 10 mV, V2 in the order of 20 mV, and V3 in the order of '30 mV such that the different voltage levels result in respective magnetic field strenatlis on the magnetic disk surface.

0 0 A decimal four bit number has four "bits" and each "bit" can have four values: 0, 1,2 or 3). Each of the four values is represented by a different voltage level and, in the present example, as shown in Figure 6, value 0 is represented by voltage level VO, value 1 is represented by voltage level V1, value 2 is represented by voltage level V2 and value 3 is represented by voltage level V3.

The transducer head is therefore switched between the four voltage levels so that respective bit values can be written as data onto the disk surface. Thus, in accordance with the above example where the decimal four bit number is 10 12, the transducer head would switch between the following voltage levels: V1, then VO, V I, and V2.

By expressing the ASCII character "F" as a decimal four bit number and writing that information onto the disk surface using the respective voltage levels described above, it is apparent that the example of the invention is able to write the ASCII character using only four bits rather than the eight bits which would be required using a conventional binary encoding. This is a saving of both disk space, the example of the invention taking half the disk space which would be required for a conventional binary method, and also a time saving.

In another embodiment of the present invention, the four values of a decimal four bit number or byte can be represented on a disk surface by using 7 "bits" of different widths. Referring back to Figure 1, a binary bit "0" and a binary bit "I" occupy the same width on a track of a magnetic disk. In accordance with this embodiment of the present invention, each of the four values of a decimal four bit has a distinct width. In the example given in Figure 2. the 0 value has the smallest width W3), the 1 value has a width W2 which is preferably twice the width of the 0 value W3, the 2 value has a width Wl which is preferably twice the width of the 1 value W2, and the 3 value has a width W which is preferably twice the width of the 2 value W1. Thus, the values can be distinguished from one another by Virtue of their respective C1 widths.

The various widths can be written onto a disk surface by a specialised transducer head which is split into four adjacent write heads. Depending upon the value to be written to the disk surface, respective ones of the adjacent write heads are actuated to write a respective width. In this manner, the thickness of the "bit" to be written on the disk surface can be varied.

Similarly, when reading from a disk surface having data encoded thereon in the above described manner, a transducer head having four discrete but adjacent read heads of the same configuration as the four adjacent vmte heads can be used. Only those read heads which are located above a width of track which has been written to will have a voltage induced in them. Thus, the width of the "bit" included on the track below the transducer head can be detected and, from that width, the value of the "bit" can be derived.

Another variation on the above described embodiment encodes each "bit" from a decimal four bit number by using four discrete magnetic field strengths to represent the respective four values of a bit. The manner in which the respective magnetic field strengths are applied to the magnetic disk surface can

1 be achieved in a number of ways and include varying the voltage applied by the transducer head, varying the current applied by the transducer head and varying the physical dimensions of the area of the transducer head which carries out the writing function.

The invention can be applied to optical disks as well as to magnetic disks. As described with reference to Figures 3 and 7, the power level of a write laser determines the depth or height of the pit produced on the optical disk to encode a bit of information. For example, in the case of a CD, this operation would be carried out on the photo-resist material used to create the master or father stamper used to produce the resultant CD. In accordance with an example of the invention, the laser beam which writes information to the optical disk (the photo-resist material in the case of a CD master stamper) is switchable between a number of power levels, there being four power levels in the present example. Accordingly, as shown in Figures 4 and 8, a transducer head for use with a method and apparatus embodying the present invention is switchable between four power levels: PO, P 1, P2 and P3. The first and lowest power level PO which is preferably 0 W does not produce a pit. However, the subsequent power levels ranging from the lowest, P 1, to the highest, P3), do produce pits C which have a depth which is substantially, proportional to the respective power level applied. Thus, as shown in Figure 9, the laser on the transducer head can be used to produce pits of different depths to represent the respective values of the "bit" to be encoded on the disk, a land or no pit representing the 0 value, a pit of depth H2 representing the 1 value, a pit of depth H1 representing the 2 value, and a pit of depth H (being the maximum pit depth obtainable) representing the 3 value.

As previously described, when the transducer head is in read mode, to read data from the optical disk, the amplitude of light reflected from the various 3 pits and lands on the optical disk is indicative of the type of pit or land from which the light has been reflected. Thus, the electro-optical detector can distinguish between the respective values which are encoded in a "bit". Thus, the variations in the amplitude or power of the light reflected from the optical disk can be translated into the values 0, 1,2, and 3 3.

The above description is concerned with the use of a byte comprising a decimal four bit number whicli is converted from a decimal number or directly from an ASCII character. Using the same methodology it is possible to envisage other embodiments of the invention which use, for example, decimal two bit numbers or decimal one bit numbers to represent each of the 256 ASCII characters. Taking the example of a decimal two bit number, this would be made up of two values as opposed to the four values which make up a decimal four bit number. For example, considering the case of the ASCII character having a decimal equivalent of 255, this character would be represented by the decimal two bit number of 1515, Le. two values of 15.

The decimal number to be converted, 255, is divided by 16 to give a quotient q I of 15 and a remainder r I of 15; and the quotient q I of 15 is divided by 16 to give a quotient q2 of 0 and a remainder r2 of 15.

In order to encode a decimal two bit number on a magnetic disk, the transducer head must be switchable between 16 voltage or power levels so as to achieve the necessary number of discrete levels which are needed to represent the respective 16 possible values of each "bit" of the decimal two bit number. Preferably, the voltage level required to store the decimal two bit number 15 is the same as the voltage level required to store the binary bit "I" (a maximum value) and the voltage level required to store the decimal two bit number 0 is 10 H the same as the voltage level required to store the binary bit "0" (a minimum value). Further, the values intermediate the minimum and maximum values are advantageously represented by fractions of the maximum value, the increment between respective values of a bit being identical. Table 2 has five columns: a decimal number; its binary equivalent; its hexadecimal equivalent; the ASCII equivalent; and the so-called decimal two bit number produced in accordance with an embodiment of the invention. Each of the 256 ASCII characters used by a computer are converted to a so-called decimal two bit number.

To store the ASCII character "Y" having a decimal equivalent of 89 as a decimal one bit number, the decimal equivalent is first divided by 256 to calculate the quotient qI and the remainder rl. In this case, the quotient is 0 and the remainder is 89. Thus, the equivalent decimal one bit number to ASCII character number 89 is 89.

In order to encode a decimal one bit number on a magnetic disk, the transducer head must be switchable bet-ween 256 voltage or power levels so as to achieve the necessary number of discrete levels which are needed to represent the respective 256 possible values of the single "bit" of the decimal one bit number. Preferably, the voltage level required to store the decimal one bit number 255 is the same as the voltage level required to store the binary bit "I" and the voltage level required to store the decimal one bit number 0 is the same as the voltage level required to store the binary bit "0". Further, the values intermediate the minimum and maximum values are advantageously represented by fractions of the maximum value, the increment between respective values of a bit being identical. Table.3 has five columns: a decimal number; its binary equivalent; its hexadecimal equivalent; the ASCII equivalent; and the so-called decimal one bit number produced in accordance j 1 with an embodiment of the invention. Each of the 256 ASCII characters used by a computer are converted to a so-called decimal one bit number.

It is to be appreciated that there are other methods which could be envisaged for recording decimal four bit numbers, decimal two bit numbers and decimal one bit numbers within the area typically used by a single binary bit on a magnetic disk or a recordable optical disk. The prime consideration is that, for example in the case of a decimal four bit number, the four possible values for each bit can be distinguished from one another. Likewise, in the case of decimal two bit numbers and decimal one bit numbers, the respective 16 possible values and 256 possible values can be distinguished from one another.

The method of encoding data according to the invention can be used with any type of recording medium. Examples have been given above of embodiments of the invention recording data on a magnetic recording medium such as a floppy disk or a hard disk drive and also in respect of an optical recording medium such as a CD-ROM or DVD. Another example of a recording medium which may be used with the method of encoding data embodying the present invention comprises the CD-R which is a recordal compact disc having a sensitive dye layer which can be burnt by a laser to encode data on the dye layer. To store data in the decimal four bit number format, the power level of the laser can be varied so as to have three bum intensities: a first burden intensity to represent the I value, a second burden intensity to represent the 2 value and a third burden intensity to represent the 3 value. When no dye is burnt by the laser, this represents the 0 value. Similarly, when using the decimal two bit number format, 15 bum intensities C> are required and when using the decimal one bit number format, 255 bum intensities are required.

2- 1 A further example of a recording medium which may be used with the method of encoding data embodying the present invention comprises the CDIn RW (read/write, also known as CD-E, erasable). The CD-RW includes a surface alloy of silver, indium, antimony and tellurium which can have varying states of reflectivity, varying between a high and a low state depending on the power level of the laser impinged on the alloy. Intermediate states of 0 reflectivity between a high level and a low level can be used to represent the respective values of a decimal four bit number, a decimal two bit number, or a decimal one bit number. The different reflectivity values obtained when reading the CD-M can be translated into the respective values of the decimal bit numbers.

j3 I'ABLE ()i.'CONVr'.1z,',ION P'OR DECPv1AL, BINARY, 111-.XAI)]7CIMAI,, ASCIINNT) DECIMAL FOUR BIT DECIMAL BINARY HEXADECIMAL ASCII DECIMAL FOUR BIT 0 00000000 00 XUL 0 0 0 0 1 00000001 01 SOH 0 0 0 1 9 000000 10 02 STX 0 0 0 2 000000 11 01) ETX 0 0 0 13 4 000001 00 04 EOT 0 0 1 0 000001 01 05 ENQ 0 0 1 1 6 000001 10 06 ACK 0 0 1 2 7 000001 11 07 BEL 0 0 1 3 8 0000 1000 08 BS 0 0 2 0 1 1 9 0000 1001 09 HT 0 0 1 1.0 0000 10 10 OA LF 0 0 11 0000 10 11 OB IVIT 0 0 2 3 12 0000 11 00 OC FF 0 0 3 0 000011 01 OD CR 0 0 3 1 14 0000 11 10 OE so 0 0 3 2 0000 11 11 OF S1 0 0 3 3 16 0001 0000 10 DLE 0 1 0 0 17 0001 0001 11 DC1 0 1 0 1 18 0001 00 10 12 DC2 0 1 0 2 19 0001 00 11 13 DC3 0 1 0 13 0001 01 00 14 DC4 0 1 1 0 21 0001 01 01 15 NAK 0 1 1 1 22 0001 01 10 16 SYN 0 1 1 2 17 ETB 0001 01 11 0 1 1 24 0001 1000 18 CAN 0 1 2 0 0001 1001 19 EM 0 1 2 1 26 0001 10 10]A SUB 0 1 2 2 27 0001 1011 IB ESC 0 1 2 3 28 0001 11 00 ic FS 0 1 J1 0 29 0001 11 01 ID GS 0 1 3 1 0001 11 10]E RS 0 1 3) 2 0001 11 11 IF us 0 1 -3 3 12 00 100000 20 SP 0 2 0 0 J) 00 100001 21 1 0 2 0 1 3 4 c )4 00 1000 10 22 0 2 0 2 3 )5 00 1000 11 23) 0 2 0 Authors: X1r. DAN DOBRE and Mr. COSTICA DOBRE page 2 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL FOUR BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECINIAL FOUR BIT 3 6 00 1001 00 24 S 0 2 1 0 3 57 00 1001 01 25 % 0 2 1 1 38 00 1001 10 26 & 02 1 2 19 j 00 1001 11 27 0 2 1 33 00 10 1000 28 0 2 2 0 41 00 10 1001 29 0 2 2 1 42 00 10 10 10 2A 0 2 2 2 43 00 10 10 11 213 + 0 2 2 3) 44 00 10 11 00)c 1 0 2 3 0 00 10 11 01 2D 0 ? 13 1 46 00 10 11 10 2E 0 2 3 2 47 00 10 11 11 2F 0 2 31 3 48 00 11 0000 3 0 0 0 0 0 49 00 11 0001 33 1 1 0 0 1 00 11 00 10.37 0 3 0 2 51 00 11 00 11 0 1) 0 52 00 11 01 00 3 4 4 0 3 1 0 -33 00 11 01 01 335 5 0 3 1 1 54 00 11 01 10 3 6 6 0 3) 1 2 00 11 01 11 3 7 7 0 3 1 3) 56 00 11 1000 3 8 8 0 J3) 2 0 57 00 11 1001 -39 9 0 3) 2 1 58 00 11 10 10 3 A 0 3 2 2 59 00 11 10 11 3 B 0 3) 2 3) 00 11 11 00.3 C < 0 -3 3 0 61 00 11 11 01 33 D 0 3 3 1 62 00 11 11 10 33 E > 0 3) J3) 2 6 3 00 11 11 11 3) F 1) 0 3 3) 3) 64 01 000000 40 @ 1 0 0 0 01 000001 41 A 1 0 0 1 66 01 0000 10 42 B 1 0 0 2 67 01 0000 11 43 c 1 0 0.1) 68 01 0001 00 44 D 1 0 1 0 69 01 0001 01 45 E 1 0 1 1 01 0001 10 46 F 1 0 1 2 71 01 0001 11 47 G 1 0 1 3 72 01 00 1000 48 H 1 0 2 0 7 -3) 01 00 1001 49 1 1 0 2 1 74 01 00 10 10 4A j 1 0 2 2 01 00 10 11 4B K 1 0 2 -3) 76 01 00 11 00 4C L 1 0 3 0 77 01 001101 4D NI 1 0 3 1 Authors: Mr. DAN DOBRE and Mr. COSTICA DOBRE is Authors: Mr. DAN DOBRE and Mr. COSTICA DOBRE page 3 (Decimal, Binary, Hexadecimal, ASCII and DECIlkLAL FOUR BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL FOUR BIT 78 01 00 11 10 4E N 1 0 3 2 79 01 00 11 11 4F 0 1 0 3 3 so 01 01 0000 50 p 1 1 0 0 81 01 01 0001 51 Q 1 1 0 1 82 01 01 00 10 52 R 1 1 0 2 8 J1 01 01 00 11 53 S 1 1 0 3 84 01 01 01 00 54 T 1 1 1 0 010101 01 55 U 1 1 1 1 86 01 01 01 10 56 v 1 1 1 2 87 010101 11 57 W 1 1 1 13 88 01 01 1000 58 X 1 1 2 0 89 0101 1001 59 y 1 1 2 1 0101 10 10 5A z 1 1 2 2 91 01 01 10 11 5B 1 1 2 3 92 01 01 1100 5C 1 1 3 0 9-11 0101 1101 5D 1 1 3 1 94 0101 11 10 SE 1 1 3 2 01 01 11 11 5F 1 1 3 3 96 01 100000 60 1 2 0 0 97 01 100001 61 a 1 2 0 1 98 01 1000 10 62 b 1 2 0 2 99 01 1000 11 63 c 1 2 0 3 01 1001 00 64 d 1 2 1 0 101 01 1001 01 65 c 1 2 1 1 102 01 1001 10 66 f 1 2 1 2 101) 01 1001 11 67 c, 1 2 1 3) 104 01 10 1000 68 h 1 2 2 0 01 10 1001 69 1 2 2 1 106 01 10 10 10 6A 1 2 2 2 107 01 10 10 11 6B k 1 2 2 3 108 01 1011 00 6C 1 1 2 3) 0 109 01 10 11 01 61) m 1 2 3 1 01 10 11 10 6E n 1 2 3 2 01 1011 11 6F 0 1 2 3 -3) 112 01 11 0000 70 p 1.1) 0 0 113 01 11 0001 71 q 1 3 0 1 114 01 11 00 10 72 r 1 3 0 2 01 11 00 11 73 S 1 3 0 3 116 01 11 01 00 74 t 1 3 1 0 117 01 11 01 01 75 U 1 3 1 1 118 01 11 01 10 76 v 1 3 1 2 119 01 11 01 11 77 W 1 3 1 3) Authors: Mr. DAN DOBRE and Mr. COSTICA DOBRE page 4 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL FOUR BIT Conversion Table) DECIMAL BINARY HEX.ADECLMAL ASCII DECII,IAL FOUR BIT 01 11 1000 78 X 1 3 2 0 12 1 01 11 1001 79 y 1 3 2 1 01 11 10 10 7A 1 -)) 123 01 11 10 11 7B 1 3) 2 3) 1 0 124 01 11 11 00 7C 01 11 1101 71) 1 31 1 1 c 1 ' ' ') 126 01 11 11 10 7E 127 01 11 11 11 7F DEL J) 12 8 10000000 so 2 0 0 0 129 10000001 81 2 0 0 1 100000 10 82 2 0 0 2 1-171 100000 11 83 2 0 0 -3) 1 312 100001 00 84 2 0 1 0 133 100001 01 85 2 0 1 1 134 100001 10 86 2 0 1 2 1 3) 5 100001 11 87 2 0 1 3) 136 1000 1000 88 2 0 2 0 137 1000 1001 89 2 0 2 1 138 1000 10 10 8A 2 0 2 2 1-39 1000 10 11 8B 2 0 2 35 1000 11 00 8C 2 0 3) 0 141 1000 11 01 8D 2 0 3 1 142 1000 11 10 8E 2 0 J3) 2 14-33 1000 11 11 SF 2 0 3 3 144 1001 0000 90 2 1 0 0 1001 0001 91 2 1 0 1 146 1001 00 10 92 2 1 0 2 147 1001 00 11 93 2 1 0 -3) 148 1001 01 00 94 2 1 1 0 149 1001 01 01 95 2 1 1 1 1001 01 10 96 2 1 1 2 151 1001 01 11 97 2 1 1 15 15.2 1001 1000 98 2 1 2 0 1533 1001 1001 99 2 1 2 1 154 1001 10 10 9A 2 1 2 2 1001 10 11 9B 2 1 2 3) 156 1001 11 00 9C 2 1 -3) 0 157 1001 11 01 91) 2 1 3 1 158 1001 11 10 9E 2 1 3 2 159 1001 11 11 9F 2 1 3 3 10 100000 AO 2 2 0 0 161 10 100001 A 1 2 2 0 1 1"- Atifliors. 'Ar. DAN DOBRE and Mr. COSTICA DOBRE page 5 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL FOUR BIT Conversion Table) DECRI IAL BINARY HEXADECIMAL ASCII DECIMAL FOUR BIT 162 10 1000 10 A22 2 2 0 2 163 10 1000 11 A-33 2 2 0 3 164 10 1001 00 A4 2 2 1 0 10 1001 01 AS 2 2 1 1 166 10 1001 10 A6 2 2 1 2 167 10 1001 11 A7 2 2 1 3 168 10 10 1000 A8 2 2 2 0 169 10 10 1001 A9 2 2 2 1 10 10 10 10 AA 2 2 2 2 171 10 10 10 11 AB 2 2 2 3 172 10 10 11 00 AC 2 2 3 0 173 10 10 11 01 AD 2 2 3 1 174 10 10 11 10 AE 2 2 -3 2 10 10 11 11 AF 2 2 J3) 3 176 10 11 0000 BO 2 3) 0 0 177 10 11 0001 B1 2 3 0 1 178 10 11 00 10 B2 2 35 0 2 179 10 11 00 11 B33 2 J3) 0 3 10 11 01 00 B4 2 -3) 1 0 181 10 11 01 01 B5 2 3 1 1 182 10 11 01 10 B6 2 3) 1 2 181) 10 11 01 11 B7 2 3) 1 J3) 184 10 11 1000 B8 2 3) 2 0 10 11 1001 B9 2 3) 2 1 186 10 11 10 10 BA 2 3) 2 2 187 10 11 10 11 BB 2 3 2 3 188 10 11 11 00 BC 2 -3) J3) 0 189 10 11 11 01 BD 2 3) 3 1 10 11 11 10 BE 2 3 3 2 191 10 11 11 11 13F 2 3 37 3 19:11 11 000000 C0 3 0 0 0 193 11 000001 cl 0 0 1 194 11 0000 10 C2 0 0 2 11 0000 11 c 3 0 0 3 196 11 0001 00 C4 0 1 0 197 11 0001 01 C5 -3 0 1 1 198 11 0001 10 C6 3) 0 1 2 199 11 0001 11 C7 0 1 3 11 00 1000 C8 0 2 0 201 11 00 1001 C9 0 2 1 202 11 00 10 10 CA 0 2 2 2 0 3 11 00 10 11 CB 0 2 3 1 Authors: Mr. DAN DOBRE and Mr.COSTICA DOBRE page 6 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL FOUR BIT Conversion Table) DECIMAL BrNARY HEXADECIMAL ASCII DECIMAL FOUR BIT 204 11 00 1100 cc 3 0 3 0 205 11 00 1101 CD 3 0 3 1 206 11 00 11 10 CE 3 0 3 2 207 11 00 11 11 CF 3 0 3 3 208 11 Ol 0000 DO _3 1 0 0 209 11 01 0001 D I 1 0 1 210 11 Ol 00 10 D2 1 0 2 211 11 0100 11 D3 _3 1 0 1101 01 00 D4 _3 I 1 0 21 33 1101 0101 D5 _3 I I I 214 11 01 01 10 D6 1 1 2 215 11 01 01 11 D7 _3 1 1 3 216 11 01 1000 D8 3 1 2 0 217 1101 1001 D9 1 2 1 218 1101 10 10 DA 3 1 2 2 219 1101 10 11 DB 3 1 2 3) 220 1101 1100 DC 3 1 3) 0 1 221 1101 1101 DD 3 1 3 1 222 1101 11 10 DE.3 1 3 2 223 1101 11 11 DF 3 1 3 3 224 11 100000 EO 3 2 0 0 225 11 100001 El _3 2 0 1 226 11 1000 10 E2 2 0 2 227 11 1000 11 E3 3 2 0 3 228 11 1001 00 E4 _3 2 1 0 229 11 1001 01 E5 _3 2 1 1 230 11 1001 10 E6 _3 2 1 2 23) 1 11 1001 11 E7.3 2 1 3 23) 2 11 10 1000 E8 2 2 0 2 3 3 11 10 1001 E9 3 2 2 1 234 11 10 10 10 EA 3 2 2 2 2_33 5 11 10 10 11 EB 3 2 2 3 23) 6 11 10 1100 EC 3 2 3 0 2.37 11 10 11 01 ED 2 3 1 238 11 10 11 10 EE 3 2 3 2 23) 9 11 10 11 11 EF 3 2 3 3 240 11 11 0000 FO 3 3 0 0 241 11 11 0001 F1 3 3 0 1 242 11 11 00 10 F2 3 _3 0 2 243) 11 11 0011 F 33 3 3 0 3 244 11 11 01 00 F4 3 3 1 0 245 11 11 01 Ol F 5 3 3 1 1 Authors: Mr. DAN DOBRE and Mr. COSTICA DOBRE page 7 (Decimal, Binary, Hexadecimal, ASCII and FOUR BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL FOUR BIT 246 11 11 01 10 F6 1 2 247 11 1101 11 F7 1 3 248 11 11 1000 F8 2 0 249 11 11 1001 F9.3 3 2 1 250 11 11 10 10 FA 3 -) 2 2 251 11 11 10 11 FB 3 3 2 3 252 11 11 11 00 FC 3 3) 3) 0 253 11 11 11 01 I'D 3 1 254 11 11 11 10 FE.3.3 2 255 11 11 11 11 FF 2-0 i FABLE 017 CONVERSION FOR DEICIMAL, BINARY, HEXADECIMAL, ASCII AND DECRIAL TWO BIT DECIMAL BINARY HEXADECIMAL ASCII DECIMAL TWO BIT 0 00000000 00 NUL 0 0 1 00000001 01 SOH 0 1 2 000000 10 02 STX 0 2 000000 11 03 ETX 0 1) 4 000001 00 04 EOT 0 4 000001 01 05 ENQ 0 5 6 000001 10 06 ACK 0 6 7 000001 11 07 BEL 0 7 8 0000 1000 08 BS 0 8 9 0000 1001 09 HT 0 9 0000 10 10 OA LF 0 10 11 0000 10 11 OB VT 0 11 ]'? 0000 11 00 OC FF 0 12 13 0000 11 01 OD CR 0 1-13 14 0000 11 10 OE so 0 14 0000 11 11 OF SI 0 15 16 0001 0000 10 DLE 1 0 17 0001 0001 11 DC] 1 1 18 0001 00 10 12 DC2 1 2 19 0001 00 11 DC3 1 0001 01 00 14 DC4 1 4 21 0001 01 01 is NAK 1 5 22 0001 01 10 16 S YN 1 6 23) 0001 01 11 17 ETB 1 7 24 0001 1000 18 CAN 1 8 0001 1001 19 EM 1 9 26 0001 10 10 1 A SUB 1 10 27 0001 1011 IB ESC 1 11 0001 1100 ic FS 1 12 29 0001 1101 1 D GS 1 13 0001 11 10 IE RS 1 14 31 0001 11 11 IF us 1 15 32 00 100000 20 SP 2 0 3_) 00 100001 21 1 2 1 3 C4 34 00 1000 10 22 2 2 3 00 1000 11 2 -3) # 2 3 Authors. Dan Dobre and Costica Dobre 2- i on Table) page 2 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL TWO BIT Convers, DECIMAL BINARY HEXADECIMAL ASCII DECIMAL TWO BIT 36 00 1001 00 24 2 4 3 7 00 1001 01 25 % 2 5 8 00 1001 10 26 & 2 6 9 00 1001 11 27 2 7 00 10 1000 28 2 8 41 00 10 1001 29 2 9 42 00 10 10 10 2A 2 10 43 00 1010 11 2B 2 11 44 00 10 11 00 2C 2 12 00 10 1101 2D 2 13 46 00 10 11 10 2E 2 14 47 00 10 11 11 2F 2 15 48 00 11 0000 0 0 1 49 00 11 0001 31 1.3 1 00 11 00 10 32 2 2 51 00 1100 11 33 3 52 00 11 01 00 34 4 3 4 -3) 00 11 01 01 35 5 3 5 54 00 11 01 10 3 6 6 6 00 11 01 11 37 7 3 7 56 00 11 1000 38 8 3 8 57 00 11 1001 39 9 9 58 00 11 10 10 3A 10 59 00 11 10 11 313 1C 00 11 1100.5 < 3 12 61 00 11 11 01 3D I 62 00 11 11 10 3E > 3 14 63 00 11 11 11 3 F ? 15 64 01 000000 40 @ 4 0 01 000001 41 A 4 1 66 01 0000 10 42 B 4 2 67 01 000011 43) C 4 3 68 01 0001 00 44 D 4 4 69 01 0001 01 45 E 4 5 01 0001 10 46 F 4 6 71 01 0001 11 47 G 4 7 72 01 00 1000 48 H 4 8 73 01 00 1001 49 1 4 9 74 01 00 10 10 4A 1 4 10 01 00 10 11 4B K 4 11 76 0100 11 00 4C L 4 12 77 01 0011 01 4D M 4 13 Authors: Dan Dobre and Costica Dobre 92- page 3 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL TWO 131T Conversion Table) DECIMAL BrNARY HEXADECIMAL ASCII DECTMIAL TWO BIT 78 01 00 11 10 4E N 4 14 79 01 00 11 11 4F 0 4 15 01 01 0000 50 p 5 0 81 01 01 0001 51 Q 5 1 82 01 01 00 10 52 R 5 2 83 01 01 00 11 533 S 5 84 01 01 01 00 54 T 5 4 01 01 01 01 55 U 5 5 86 01 01 01 10 56 v 5 6 87 01 01 01 11 57 W 5 7 88 01 01 1000 58 X 5 8 89 01 01 1001 59 Y 5 9 01 01 10 10 SA z 5 10 91 01 01 10 11 5B 5 11 92 01 01 11 00 5C 5 12 91 01 01 11 01 5D 5 13 94 01 01 11 10 5E 5 14 01 01 11 11 5F 5 15 96 01 100000 60 6 0 97 01 100001 61 a 6 1 98 01 1000 10 62 b 6 2 99 01 100011 63 c 6 -3 01 1001 00 64 d 6 4 101 01 1001 01 65 c 6 5 102 01 1001 10 66 f 6 6 103 01 1001 11 67 6 7 104 01 10 1000 68 h 6 8 01 10 1001 69 1 6 9 106 01 10 10 10 6A j 6 10 107 01 10 10 11 613 k 6 11 108 01 10 11 00 6C 1 6 12 109 01 10 11 01 61) m 6 13 01 10 11 10 6E n 6 14 ill 01 10 11 11 6F 0 6 15 112 01 11 0000 70 p 7 0 113 01 11 0001 71 q 7 1 114 01 11 00 10 72 r 7 2 01 11 00 11 733 S 7 116 01 11 01 00 74 t 7 4 117 01 11 01 01 75 U 7 5 118 01 11 01 10 76 v 7 6 119 01 11 01 11 77 W 7 7 Authors: Dan Dobre and Costica Dobre 2-3 page 4 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL TWO BIT Conversion Table) DECEMAL BINARY HEXADECIMAL ASCII DECINIAL TWO BIT 01 11 1000 78 X 7 8 121 01 11 1001 79 y 7 9 122 01 11 10 10 7A z 7 10 123 01 11 10 11 7B 7 11 124 01 11 11 00 7C 7 12 01 11 1101 71) 7 1 -3 126 01 11 11 10 7E 41 7 14 127 01 11 11 11 7F DEL 7 15 128 10000000 80 8 0 129 10000001 81 8 1 100000 10 82 8 2 1-31 100000 11 81) 8 3 132 100001 00 84 8 4 133 100001 01 85 8 5 134 100001 10 86 8 6 1 J3) 5 100001 11 87 8 7 1 3) 6 1000 1000 88 8 8 137 1000 1001 89 8 9 138 1000 10 10 8A 8 10 139 1000 10 11 8B 8 11 1000 11 00 8C 8 12 141 1000 11 01 81) 8 13 142 1000 11 10 8E 8 14 143 1000 11 11 SF 8 15 144 1001 0000 90 9 0 1001 0001 91 9 1 146 1001 00 10 92 9 2 147 1001 00 11 93 9 1) 148 1001 01 00 94 9 4 149 1001 01 01 95 9 5 1001 01 10 96 9 6 151 1001 01 11 97 9 7 152 1001 1000 98 9 8 153) 1001 1001 99 9 9 154 1001 10 10 9A 9 10 1001 10 11 913 9 11 i 156 1001 11 00 9C 9 12 157 1001 11 01 91) 9 13 158 1001 11 10 9E 9 14 159 1001 11 11 917 9 is 10 100000 AO 10 0 161 10 100001 AI 10 1 Authors: Dan Dobre and Costica Dobre 2+ page 5 (Decimal, Binary, Hexadecimal, ASCII and DECINIAL TWO BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL TWO BIT 162 10 1000 10 A2 10 2 163 10 1000 11 A3 10 3 164 10 1001 00 A4 10 4 10 1001 01 AS 10 5 166 10 1001 10 A6 10 6 167 10 1001 11 A7 10 7 168 10 10 1000 A8 10 8 169 10 10 1001 A9 10 9 10 10 10 10 AA 10 10 171 10 10 10 11 AB 10 11 172 10 10 11 00 AC 10 12 173) 10 10 11 01 AD 10 11) 174 10 10 11 10 AE 10 14 10 10 11 11 AF 10 15 176 10 11 0000 BO 11 0 177 10 11 0001 B 1 11 1 178 10 11 00 10 B2 11 2 179 10 11 00 11 B3 11 3 10 11 01 00 B4 11 4 181 10 11 01 01 B5 11 5 182 10 11 01 10 B6 11 6 18-33 10 1101 11 B7 11 7 184 1011 1000 B8 11 8 10 11 1001 B9 11 9 186 10 11 10 10 BA 11 10 187 10 11 10 11 BB 11 11 188 10 11 11 00 BC 11 12 189 10 11 11 01 BD 11 13 10 11 11 10 BE 11 14 191 10 11 11 11 BF 11 15 192 11 000000 C0 12 0 193 11 000001 c 1 12 1 194 11 0000 10 C2 12 2 11 0000 11 C3 12 3 196 11 0001 00 C4 12 4 197 11 0001 01 C5 12 5 198 11 0001 10 C6 12 6 11 0001 11 C7 12 7 11 00 1000 C8 12 8 201 11 00 1001 C9 12 9 202 11 00 10 10 CA 12 10 2033 11 00 10 11 CB 12 11 Authors. Dan Dobre and Costica Dobrc )-S page 6 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL TWO BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECINIAL TWO BIT 204 11 00 1100 cc 12 12 205 11 00 1101 CD 12 13 206 11 00 11 10 CE 12 14 207 11 00 11 11 CF 12 15 208 11 01 0000 DO 11) 0 209 11 01 0001 D 1 12 1 210 11 01 00 10 D 2 13 ? 211 110100 11 D 3 13 3 212 11 01 01 00 D4 1 3) 4 213) 1101 0101 D5 1 3) 5 214 110101 10 D6 1 3) 6 215 110101 11 D7 I'll 7 216 1101 1000 D8 1 8 217 1101 1001 D9 1 9 218 11 01 10 10 DA 11) 10 219 1101 10 11 D13 11) 11 220 1101 11 00 DC 1 3) 12 221 1101 11 01 DD 13 13 222 1101 11 10 DE 13 14 223 1101 11 11 DF 13 15 224 11 100000 EO 14 0 225 11 100001 E 1 14 1 226 11 1000 10 E2 14 2 227 11 1000 11 E3 14 3) 22 8 11 1001 00 E4 14 4 229 11 1001 01 E5 14 5 23) 0 11 1001 10 E6 14 6 231 11 1001 11 E7 14 7 232 11 10 1000 ES 14 8 2333) 11 10 1001 E9 14 9 234 11 10 10 10 EA 14 10 23) 5 11 10 10 11 EB 14 11 23 6 11 10 11 00 EC 14 12 23) 7 11 10 11 01 ED 14 1 - 23 8 11 10 11 10 EE 14 14 239 11 10 11 11 EF 14 15 240 11 11 0000 FO 15 0 241 11 11 0001 F1 15 1 242 11 11 00 10 F2 15 2 243 11 11 00 11 F 33 15 3 244 11 11 01 00 F4 15 4 245 11 11 01 01 F 5 15 5 Authors: Dan Dobre and Costica Dobre page 7 (Decimal, Binary, Hexadecimal, ASCII and TWO BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL TWO BIT 246 2 11 11 01 10 F6 15 6 247 11 11 01 11 F7 15 7 248 11 11 1000 F8 15 8 249 11 11 1001 F9 15 9 250 11 11 10 10 FA 15 10 251 11 11 1011 FB 15 11 252 11 11 11 00 K 15 12 253 11 11 11 01 FD 15 13 254 11 11 11 10 FE 15 14 255 11 11 11 11 FF 1515 Authors: Dan Dobre and Costica Dobre 2j- -T-At Le TABLE, OF CONVERSION FOR DECI MAI.. BINARY, IE,.XADECINI,l,, ASCII AND DECINIAL ONE BIT DECIMAL BINARY HEXADECIMAL ASCII DECIMAL ONE BIT 0 00000000 00 NUL 0 1 00000001 01 SOH 1 2 000000 10 02 STX 2 n 1 000000 11 01) ETX.3 4 000001 00 04 EOT 4 000001 01 05 E Ni. Q 5 6 000001 10 06 ACK 6 7 000001 11 07 BEL 7 8 0000 1000 08 BS 8 9 0000 1001 09 HT 9 0000 10 10 OA LF 10 11 0000 10 11 OB VT 11 12 000011 00 OC FF 12 13 0000 11 01 OD CR 13 14 0000 11 10 OE so 14 000011 11 OF SI 15 16 0001 0000 10 DLE 16 17 0001 0001 11 DC1 17 18 0001 00 10 12 DC2 18 19 0001 00 11 13 DC3 19 0001 01 00 14 DC4 20 21 0001 01 01 is NAK 21 22 0001 01 10 16 SYN 22 233 0001 01 11 17 ETB 23 24 0001 1000 18 CAN 24 0001 1001 19 EM 25 26 0001 10 10 IA SUB 26 27 0001 10 11 IB ESC 27 28 0001 1100 IC FS 28 29 0001 11 01 ID GS 29 10 0001 11 10 IE RS 1 1 1 0001 11 11 IF us 332 00 100000 20 SP 32 33 00 100001 21 33 3 )4 00 100010 22 3 4 3 00 1000 11 23 4 35 Authors: Dan Dobre and Costica Dobre 2-9 page 2 (Decimal, Binary, Hexadecimal, ASCII and DUPWAL 0.NE 131T Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL ONE BIT 36 00 1001 00 24 $ 33 6 37 00 1001 01 25 % 3 7 38 00 1001 10 26 & 3 8 39 00 1001 11 27 1 339 00 10 1000 28 40 41 00 10 1001 29 41 42 00 10 10 10 2A 42 4 3 00 10 10 11 2B + 4 3 44 00 10 11 00 2C 44 00 10 11 01 21) 45 46 00 10 11 10 2E 46 47 00 10 11 11 2F 47 48 00 11 0000 330 0 48 49 00 11 0001 31 1 49 00 11 00 10 32 2 50 51 00 11 00 11 -35 3 1 51 52 00 11 01 00 3 4 4 52 -3) 00 11 01 01 35 5 53 54 00 11 01 10 3 6 6 54 00 11 01 11 37 7 55 56 00 11 1000 38 8 56 57 00 11 1001 39 9 57 58 00 11 10 10 3 A 58 59 00 11 10 11 3 B 59 00 11 11 00 3 C < 60 61 00 11 11 01 3 D 61 62 00 11 11 10 33 E > 62 63) 00 11 11 11 3 F ? 63) 64 01 000000 40 @ 64 01 000001 41 A 65 66 01 0000 10 42 B 66 67 01 0000 11 4 -3) C 67 68 01 0001 00 44 D 68 01 0001 01 45 E 69 01 0001 10 46 F 70 71 01 0001 11 47 G 71 72 01 00 1000 48 H 72 733 01 00 1001 49 1 7 -33 74 01 00 10 10 4A j 74 01 00 10 11 4B K 75 76 01 00 11 00 4C L 76 77 01 00 11 01 41) m 77 Authors.. Dan Dobre and Costica Dobrc -9 page 3 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL ONE BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL ONE BIT 78 01 00 11 10 4E N 78 79 01 00 11 11 4F 0 79 so 01 01 0000 50 p 80 81 01 01 0001 51 Q 81 82 01 01 00 10 52 R 82 8 3 01 01 00 11 53 S 83 84 01 01 01 00 54 T 84 01 01 01 01 55 U 85 86 01 01 01 10 56 v 86 87 01 01 01 11 57 W 87 88 01 01 1000 58 X 88 89 01 01 1001 59 y 89 01 01 10 10 5A z 90 91 01 01 10 11 5B 91 92 01 01 11 00 5C 92 9-3 01 01 11 01 513 9 3 94 01 01 11 10 5E 94 01 01 11 11 5F 95 96 01 100000 60 96 97 01 100001 61 a 97 98 01 1000 10 62 b 98 99 01 1000 11 6 -3) c 99 01 1001 00 64 d 100 101 01 1001 01 65 c 101 102 01 1001 10 66 f 102 103 01 1001 11 67 er 103 It) 104 01 10 1000 68 h 104 01 10 1001 69 1 105 106 01 10 10 10 6A j 106 107 01 10 10 11 6B k 107 108 01 10 11 00 6C 1 108 109 01 10 11 01 6D 109 01 10 11 10 6E n 110 ill 01 10 11 11 6F 0 ill 112 01 11 0000 70 p 112 113 01 11 0001 71 q 1113 114 01 11 00 10 72 r 114 01 11 00 11 733 S 115 116 01 11 01 00 74 t 116 117 01 11 01 01 75 U 117 118 01 11 01 10 76 v 118 119 01 11 01 11 77 W 119 Authors. Dan Dobre and Costica Dobre page 4 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL ONE BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL ONE BIT 01 11 1000 78 X 120 121 01 11 1001 79 y 121 122 01 11 10 10 7A z 122 12-33 01 11 1011 713 123 124 01 11 11 00 7C 124 01 11 11 01 7D 125 126 01 11 11 10 7E 126 127 01 11 11 11 7F DEL 127 128 10000000 80 128 129 10000001 81 129 1-30 100000 10 82 13 0 11) 1 100000 11 83 131 132 100001 00 84 l.3 2 13 3 100001 01 85 133 1 -3 4 100001 10 86 13 4 1 -33 5 100001 11 87 1-35 136 1000 1000 88 136 1 J3) 7 1000 1001 89 13 7 138 1000 10 10 8A 138 139 1000 10 11 8B 139 1000 11 00 8C 140 141 1000 11 01 81) 141 142 1000 11 10 8E 142 14-33 100011 11 8F 1433 144 1001 0000 90 144 1001 0001 91 145 146 1001 00 10 92 146 147 1001 00 11 91) 147 148 1001 01 00 94 148 149 1001 01 01 95 149 1001 01 10 96 150 151 1001 01 11 97 151 152 1001 1000 98 152 3 1001 1001 99 1533 154 1001 10 10 9A 154 1001 10 11 9B 155 156 1001 11 00 9C 156 157 1001 11 01 9D 157 158 1001 11 10 9E 158 159 1001 11 11 9F 159 10 100000 AO 160 161 10 100001 A 1 161 Authors: Dan Dobre and Costica Dobre L3 f page 5 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL ONE BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECINIAL ONE BIT 162 10 1000 10 A2 162 16-33 10 1000 11 A3 1633 164 10 1001 00 A4 164 10 1001 Ol A5 165 166 10 1001 10 A6 166 167 10 1001 11 A7 167 168 10 10 1000 AS 168 169 10 10 1001 A9 169 10 10 10 10 AA 170 171 10 10 10 11 AB 171 172 10 10 11 00 AC 172 17 3) 10 10 11 01 AD 173 174 10 10 11 10 AE 174 10 10 11 11 AF 175 176 10 11 0000 BO 176 177 10 11 0001 B 1 177 178 10 11 00 10 B2 178 179 10 11 00 11 B3 179 10 11 01 00 B4 ISO 181 1011 01 01 B5 181 182 1011 01 10 B6 182 1811 1011 01 11 B7 183 184 1011 1000 B8 184 10 11 1001 B9 185 186 10 11 10 10 BA 186 187 10 11 10 11 BB 187 188 10 11 11 00 BC 188 189 10 11 11 01 BD 199 10 11 11 10 BE 190 191 10 11 11 11 BF 191 192 11 000000 Co 192 19.3 11 000001 CI 193 194 11 0000 10 C2 194 11 0000 11 C3 195 196 11 0001 00 C4 196 197 11 0001 01 C5 197 198 11 0001 10 C6 198 199 11 0001 11 C7 199 11 00 1000 C8 200 201 11 00 1001 C9 201 202 11 00 10 10 CA 202 203 11 00 10 11 CB 203 Authors: Dan Dobre and Costica Dobre 32- page 6 (Decimal, Binary, Hexadecimal, ASCII and DECIMAL ONE BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECINIAL ONE BIT 204 11 00 11 00 cc 204 205 11 00 11 01 CD 205 206 11 00 11 10 CE 206 207 11 00 11 11 CF 207 208 11 01 0000 DO 208 209 11 01 0001 D 1 1-109 210 11 01 00 10 D2 210 211 11 01 00 11 D-33 211 212 11 01 01 00 D4 212 213 11 01 01 01 D5 2 13 214 11 01 01 10 D6 214 215 11 0101 11 D7 215 216 11 01 1000 D8 9 16 217 11 01 1001 D9 217 218 11 01 10 10 DA 218 219 11 01 10 11 DB 219 220 11 01 1100 DC 220 221 1101 1101 DD 221 222 1101 11 10 DE 222 2233 11 01 11 11 DF 223 224 11 100000 EO 224 225 11 100001 EI 22 5 226 11 1000 10 E2 226 227 11 1000 11 E3 227 228 11 1001 00 E4 228 229 11 1001 01 E5 229 2 J3) 0 11 1001 10 E6 230 23) 1 11 1001 11 E7 23 1 232 11 10 1000 E8 23)2 2 -33 33 11 10 1001 E9 23) 3 2.33 4 11 10 10 10 EA 2 13 4 2-33 5 11 10 10 11 EB 235 23) 6 11 10 11 00 EC 2.33 6 237 11 10 11 01 ED 213) 7 238 11 10 11 10 EE 2 -3) 8 239 11 10 11 11 EF 2 3 9 240 11 11 0000 FO 240 241 11 11 0001 F 1 241 242 11 11 00 10 F2 242 243 11 11 00 11 F3 24-33 244 11 11 01 00 F4 244 245 11 11 01 01 F5 245 Authors: Dan Dobre and Costica Dobre W pacre 7 (Decimal, Binary, Hexadecimal, ASCII and ONE BIT Conversion Table) DECIMAL BINARY HEXADECIMAL ASCII DECIMAL ONE BIT 246 11 11 01 10 F6 246 247 11 11 01 11 F7 247 248 11 11 1000 F8 248 249 11 11 1001 F9 249 250 11 11 10 10 FA 250 251 11 11 10 11 F13 251 252 11 11 11 00 K 252 2 5 35 11 11 11 01 FD 2535 254 11 11 11 10 FE 254 255 11 11 11 11 FF 255 Authors: Dan Dobre and Costica Dobre 34

Claims

CLAIMS:

1. A method of encoding C, data for recordal on a recording medium :1 comprising the steps of.. converting the data into a byte having a number of bits, C) each bit having more than two possible values.

2. A method according to Claim 1, wherein the data to be encoded comprises an ASCII character.

3. A method according to Claim 1 or 2, wherein the byte has four bits and each bit has four possible values.

4. A method according to Claim 1 or 2, wherein the byte has two bits and each bit has 16 possible values.

5. A method according to Claim 1 or 2, ",-herein the byte has one bit and 0 the bit has 256 possible values.

6. A method according to any preceding claim, further comprising the step of converting the data in the form of a decimal number to the byte having a number of bits, each bit havino more than two values.

0

7. A method according to any preceding claim, comprising the step of defining the values of a bit between a minimum value and a maximum value, the minimum value corresponding to a value for encoding a conventional binary bit "0" and the maximum value corresponding to a value for encoding a conventional binary bit " 1 1 1

8. A method according to Claim 7, wherein values of the bit intermediate 0 the minimum value and the maximum value are represented by fractions of the maximum value, the increment between respective values of a bit being identical.

9. A method according to any, preceding claim, wherein each value of a bit is represented by a predetermined voltage, current, power, magnetic field strength, or light intensity.

10. A method according to any one of Claims. 1 to 8, wherein each value of a bit is represented by a predetermined shape to be recorded on a recording medium.

11. A method according to Claim 10, wherein each value of a bit is represented by a respective dimension of a shape to be recorded on the recording medium.

12. A method according, to Claim 11, wherein the dimension is a width of the shape.

13. A method according to any preceding claim comprising the further step of recording the encoded data on the recording medium.

14. An apparatus for encoding data on a recording medium comprising means to convert the data into a byte having a number of bits, each bit having more than two possible values.

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15. An apparatus according to Claim 14, wherein a transducer is provided to record the encoded data on the recording medium.

16. An a paratus according to Claim 15, wherein the transducer is p 0 switchable bet,,,veen more than two possible outputs.

17. An apparatus according to Claim 16, wherein the transducer is 0 switchable between four possible discrete outputs.

18. An apparatus according to Claim 16, wherein the transducer is switchable between 16 possible discrete Outputs.

19. An apparatus according to Claim 16, wherein the transducer is 0 switchable between 256 possible discrete outputs.

20. An apparatus according to any one of Claims 15 to 19, wherein the C recording medium is a magnetic disk and the transducer is a magnetic transducer.

21. An apparatus according to any, one of Claims 15 to 19, wherein the 0 recording medium is an optical disk and the transducer is a laser source.

22. An apparatus according to any, one of Claims 14 to 21, wherein process are means are provided to convert the data into the byte having a number of bits, each bit having more than two possible values.

23. A recording medium encoded with data in accordance with the method 0 of any one of Claims 1 to 13.

24. A method or apparatus substantially as hereinbefore described with reference to and as shown in 2,4,6 and 8.

25. Any novel feature or combination of features disclosed herein.

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