XOR may mean Exclusive or logic XOR cipher , an encryption algorithm XOR gate XOR video game XOR video game x86 instruction listings XOR , an x86 instruction disambig cs XOR es XOR eo XOR fr XOR homonymie it XOR hu XOR egy rtelm s t lap ro XOR sk XOR ... more details
About XOR in the sense of an electronic logic gate e.g. CMOS 4030 XOR in the purely logical sense Exclusive disjunction other uses XOR disambiguation class wikitable align right bgcolor ddeeff align center colspan 2 INPUT br A B OUTPUT br A XOR B bgcolor ddffdd align center 0 0 0 bgcolor ddffdd align center 0 1 1 bgcolor ddffdd align center 1 0 1 bgcolor ddffdd align center 1 1 0 The XOR gate ... shown on the right. A way to remember XOR is one or the other but not both . It represents the inequality ... 0 . This function is addition modulo 2. As a result, XOR gates are used to implement binary addition in computers. A half adder consists of an XOR gate and an AND gate . Clear Symbols There are two symbols for XOR gates the military symbol which was originally developed in America and the rectangular ... . Image XOR ANSI.svg thumb 128px left ANSI Military XOR Symbol Image XOR IEC.svg frame left IEC Rectangular XOR Symbol Clear The XOR gate with inputs A and B implements the logical expression math ..., it can be constructed from other available gates. An XOR gate can be trivially constructed from ... B math , we can construct an XOR gate directly using AND, OR and NOT gates. However, this approach requires four gates of three different kinds. An XOR gate can be made from four NAND or five NOR ... text align center margin 1em auto 1em auto image XOR from NAND.svg frame right XOR gate constructed ... two signals are fed into an XOR gate, then the output of that gate is fed into a second XOR gate ... 74LVC1G386 data sheet ref . Applications Uses in Addition The XOR logic gate can be used ... . Since the trailing sum bit in this output is achieved with XOR, the preceding carry bit is calculated ... AND XOR circuit may be chained together in order to add ever longer binary numbers. File Half Adder.svg right frame Example half adder circuit diagram Signal crossing XOR gates can be used ... XOR gates, strategically positioned to cancel out the effects of each other. A similar result can ... more details
Refimprove date July 2009 In cryptography , the simple XOR cipher is a type of additive cipher , ref Harvnb Tutte 1998 p 3 ref an encryption algorithm that operates according to the principles A math oplus math 0 A, A math oplus math A 0, A math oplus math B math oplus math C A math oplus math B math oplus math C , B math oplus math A math oplus math A B math oplus math 0 B, where math oplus math denotes the exclusive disjunction XOR operation. This operation is sometimes called modulus 2 addition or subtraction, which is identical . ref Harvnb Churchhouse 2002 p 11 ref With this logic, a string of text can be encrypted by applying the bitwise XOR operator to every character using a given key. To decrypt the output, merely reapplying the XOR function with the key will remove the cipher. For example, the string Wiki 01010111 01101001 01101011 01101001 in 8 bit ASCII can be encrypted with the repeating key 11110011 as follows tt 01010111 01101001 01101011 01101001 tt math oplus math tt 11110011 ... 01101001 tt The XOR operator is extremely common as a component in more complex ciphers. By itself, using a constant repeating key, a simple XOR cipher can trivially be broken using frequency analysis .... Its primary merit is that it is simple to implement, and that the XOR operation is computationally inexpensive. A simple repeating XOR cipher is therefore sometimes used for hiding information in cases ..., the XOR cipher is much more secure than when there is key repetition within a message. ref Harvnb ... is a one time pad , which is unbreakable even in theory. In any of these ciphers, the XOR ... External links https chris.dod.net xor xor.php Solving the Basic XOR Cipher http www.programmer2programmer.net tips encryption decryption XOR Encryption.aspx XOR Encryption http www.known issues.net allgemein simple xor encryption.html XOR code snippets Category Stream ciphers es Cifrado XOR sl XOR ifriranje uk XOR zh ... more details
Infobox VG title XOR image caption developer Astral Software publisher Logotron Ltd designer engine released 1987 genre Puzzle game modes Single player ratings platforms ZX Spectrum , Commodore 64 , Amstrad ... input Computer keyboard, joystick XOR is a computer puzzle game created by Astral Software and published ... and the Game Boy Advance . XOR is a pure puzzle game with no random or arcade elements, as summed ... in XOR s labyrinthine palace, and there is no premium on hand eye coordination . You have all the time ... and tactical problem solving are part of the XOR experience. And XOR is not simply about finding ... of the Order of XOR. Gameplay Objective The player controls two shield s, Magus and Questor ... There are two types of bomb s in XOR V bombs vertical and H bombs horizontal . V bombs shaped like jars ... teleportation portal within the maze. Related releases XOR Designer allowed players to design their own levels. XOR for Schools included six new mazes and a paper planning sheet, intended to be photocopied by teachers. ref cite news first Dave last Reeder title The Arcade XOR for Schools date ... and the planner ... ref References Reflist External links WoS game id 0005800 name XOR http www.rvvz.demon.nl xor JavaScript XOR version by Rob Veldhuyzen van Zanten http xor.ovine.net Windows XOR remake by Ovine by Design http www.gbagames.dsl.pipex.com xor home.htm Game Boy Advance XOR remake by Mick Waites http www.danceswithferrets.org xor index.htm Risc OS XOR information site including RISC OS version for download. http cookingcircle.tumblr.com post 21751571383 xor has arrived SAM Coup XOR ... art.net http www.jwm art.net XorGramana XorGramana A XOR like game for Linux using SDL, by jwm art.net, also implementing XOR . http www.level7.org.uk chroma others.html Chroma , an accurate conversion of XOR for both Windows and Linux Category 1987 video games Category Puzzle video games Category ... ZX Spectrum games ro XOR joc video ... more details
Refimprove date February 2012 Image XOR Swap.svg thumb upright 2 alt With three XOR operations the binary values 1010 and 0011 are exchanged between variables. Using the XOR swap algorithm to exchange nibble s between variables without the use of temporary storage In computer programming , the XOR swap is an algorithm that uses the exclusive disjunction XOR bitwise operation to swap computer science ... the use of a temporary storage variable. Using the XOR swap algorithm, however, no temporary storage is needed. The algorithm is as follows syntaxhighlight lang pascal X X XOR Y Y Y XOR X X X XOR Y syntaxhighlight The algorithm typically corresponds to three machine code instructions. Since XOR is a commutative operation , X XOR Y can be replaced with Y XOR X in any of the lines. When coded in assembly ... 45em Pseudocode IBM System 370 assembly x86 assembly AT&T syntax code 1 X X XOR Y 2 pascal code 1 XR R1,R2 2 asm code 1 xorl ebx, eax 2 asm code 1 Y Y XOR X 2 pascal code 1 XR R2,R1 2 asm code 1 xorl eax, ebx 2 asm code 1 X X XOR Y 2 pascal code 1 XR R1,R2 2 asm code 1 xorl ebx, eax 2 asm In the above ..., since the value stored in that location will be zeroed out by the first XOR instruction, and then remain ... their values must already be equal. Proof of correctness The binary operation XOR over bit strings of length math N math exhibits the following properties where math oplus math denotes XOR ref The first ... of an Abelian group . The last property is a structural feature of XOR not necessarily shared by other ... math A math math B math 1 code R1 R1 XOR R2 code math A oplus B math math B math 2 code R2 R1 XOR ... align math L2 br L4 br L3 3 code R1 R1 XOR R2 code math begin align A oplus B oplus A & A oplus ... example A C programming language C function that implements the XOR swap algorithm This display template .... Limited situations in which XOR swapping may be practical include On a processor where the instruction set encoding permits the XOR swap to be encoded in a smaller number of bytes In a region ... more details
Refimprove date October 2009 An XOR linked list is a data structure used in computer programming . It takes advantage of the bitwise exclusive disjunction XOR operation, here denoted by , to decrease storage ... next next prev prev prev code An XOR linked list compresses the same information into one address field by storing the bitwise XOR of the address for previous and the address for next in one field ... are at C, you can take the address of the previous item, B, and XOR it with the value in the link ... of linked list may be inadvisable General purpose debugging tools cannot follow the XOR chain, making ... that do not contain literal pointer computer programming pointer s XOR of pointers is not defined ... the addresses of the other elements of the list. Two XOR operations suffice to do the traversal ... of the current say C list item and a work register containing the XOR of the current address ... is needed in the above sequence after the two XOR operations to detect a zero result in developing ... pointer be zero. A zero pointer is a mirror . The XOR of the left and right neighbor addresses, being the same, is zero. Why does it work? The key is the first operation, and the properties of XOR X X 0 X 0 X X Y Y X X Y Z X Y Z The R2 register always contains the XOR of the address of current item C with the address of the predecessor item P C P. The Link fields in the records contain the XOR of the left and right successor addresses, say L R. XOR of R2 C P with the current link field L R yields ... R, the P R and R cancel, leaving C L. In each case, the result is the XOR of the current address with the next address. XOR of this with the current address in R1 leaves the next address. R2 is left with the requisite XOR pair of the now current address and the predecessor. Variations The underlying principle of the XOR linked list can be applied to any reversible binary operation. Replacing XOR ... as the XOR linked list, except that a zero link field is not a mirror . The address of the next node ... more details
see also RAID What is RAID Parity? A parity drive is a hard drive used in a RAID array to provide fault tolerance . For example, RAID 3 uses a parity drive to create a system that is both fault tolerant and, because of data striping , fast. ref http computer.yourdictionary.com raid Definitions of RAID configurations Retrieved on 2010 11 15 ref One way to implement a parity drive in a RAID array is to use the exclusive or , or XOR, function. XOR is a Boolean logic function which means one or the other, but not both . The XOR of all of the data drives in the RAID array is written to the parity drive. If one of the data drives fails, the XOR of the remaining drives is identical to the data of the lost drive. Therefore, the when a drive is lost, recovering the drive is as simple as copying the XOR of the remaining drives to a fresh data drive. References Reflist Category RAID Compu hardware stub ... more details
, contains the ASCII string 1000.00 . He can change that to 9500.00 by xor ing that portion of the ciphertext with the string 1000.00 xor 9500.00 . To see how this works, consider that the cipher text we send is just C K xor 1000.00 . The new message the adversary is creating is C K xor 1000.00 xor 1000.00 xor 9500.00 C K xor 1000.00 xor 1000.00 xor 9500.00 C K xor 9500.00 Recall that a string Exclusive or xor ed with itself produces all zeros and that a string of zeros xor ed with another string leaves that string intact. The result, C K xor 9500.00 , is what our ciphertext would have been if 9500 ... more details
like the one shown in the picture to the right, there are 5 outputs. Below is the expansion S0 A0 XOR B0 XOR Cin S1 A1 XOR B1 XOR A0 AND B0 S2 A2 XOR B2 XOR A1 XOR B1 AND A0 AND B0 OR A1 AND B1 S3 A3 XOR B3 XOR A2 XOR B2 AND A1 XOR B1 AND A0 AND B0 OR A2 XOR B2 AND A1 AND B1 OR A2 AND B2 S4 A4 XOR B4 XOR A3 XOR B3 AND A2 XOR B2 AND A1 AND B1 OR A3 XOR B3 AND A2 AND B2 OR A3 AND B3 References references ... more details
XEX is the callsign of the following broadcast stations in Mexico XEX TV , channel 8 in Altzomoni, M x. XEX AM , 730 kHz XEX FM , 101.7 MHz disk encryption theory Xor encrypt xor XEX XEX is also a tweakable block cipher modes of operation mode of operation of a block cipher . It may also refer to Morimoto XEX , the Michelin Star winning Tokyo restaurant of Masaharu Morimoto . disambig es XEX ... more details
PPRM may refer to Algebraic normal form Positive Polarity Reed Muller representation of a boolean function as a single algebraic sum xor of one or more conjunctions of one or more literals Greater Romania Party it would be nice to know why is this disambig ... more details
B B B N, and so on. All levels of recovery except the final one use an LDPC, which works by xor exclusive or . Xor operates on binary values, 1s and 0s. A xor B is 1 if A and B have different values and 0 if A and B have the same values. If you are given A xor B and A, you can determine the value for B. A xor B xor A B Similarly, if you are given A xor B and B, you can determine the value for A. This extends to multiple values, so given A xor B xor C xor D and any 3 of the values, the missing value can be recovered. So the recovery blocks in level one are just the xor of some set of input blocks. Similarly, the recovery blocks in level two are each the xor of some set of blocks in level one. The blocks used in the xor are chosen randomly, without repetition. However, the number of blocks xor ed to make a recovery block is chosen from a very specific distribution for each level. Since xor is a fast operation and the recovery blocks are an xor of only a subset of the blocks in the input ... is less than the present blocks in the final level. Going lower, the LDPC xor recovery level can be used ... level. Then the xor of the recovery block with all of the blocks that are present is equal to the missing ... more details
A Raid Processing Unit is an Integrated Circuit designed to implement RAID for persistent storage devices. The RPU performs calculations, such as XOR , to maintain data integrity over all connected drives in an array. RAID calculations can be performed by the computer s central processing unit CPU , but using a separate specialized chip for this task can save much array built time and increases overall usage performance. RPU s are used mainly on specialized RAID adapters. Such a RAID adapter acts as an intermediary between the array of inexpensive drives and the computers main data interface such as Conventional PCI PCI , ISA or PCI Express Most RAID adapter use a general purpose Integrated Circuit to perform array built calculations and RAID calculations. Those integrated circuits usually have a good performing XOR unit s . XOR calculations are used to compute data blocks on more advanced RAID levels like RAID 5 and RAID 6 when writing data to the persistent storage devices. Category RAID Compu hardware stub ... more details
Unreferenced auto yes date December 2009 Cover coding is a technique for obscuring the data that is transmitted over an insecure link, to reduce the risks of snooping. An example of cover coding would be for the sender to perform a bitwise Exclusive or XOR exclusive OR of the original data with a password or random number which is known to both sender and receiver. The resulting cover coded data is then transmitted from sender to the receiver, who uncovers the original data by performing a further bitwise Exclusive or XOR exclusive OR operation on the received data using the same password or random number. DEFAULTSORT Cover Coding Category Cryptography crypto stub ... more details
merge Symmetric key algorithm date January 2012 Portal Cryptography A reciprocal cipher means, just as one enters the plaintext into the cryptography system to get the ciphertext , one could enter the ciphertext into the same place in the system to get the plaintext. Sometimes also referred as self reciprocal cipher. Examples of reciprocal ciphers are Beaufort cipher Enigma machine ROT13 XOR cipher Categories Category Ciphers Crypto stub zh ... more details
byte in the input, multiply hash by the FNV prime , then XOR it with the byte from the input. The alternate algorithm, FNV 1a, reverses the multiply and XOR steps. FNV 1 hash The FNV 1 hash algorithm ... hash XOR octet of data return hash In the above pseudocode , all variables are signedness unsigned ... by the math times math symbol returns the lower 64 bits of the Product mathematics product . The XOR ... and XOR is performed ref http www.isthe.com chongo tech comp fnv index.html FNV 1a FNV 1a alternate algorithm ref hash FNV offset basis for each octet of data to be hashed hash hash XOR octet of data ... by brute force. Sticky State Being an iterative hash based primarily on multiplication and XOR, the algorithm ... bit is always the XOR of the rightmost bit of every input bit. This can be mitigated by XOR folding ... more details
Puzzles Logic mazes , sometimes called mazes with rules , are logic puzzle s with all the aspects of a tour puzzle that fall outside of the scope of a typical maze . These mazes have special rules, sometimes including multiple states of the maze or navigator. Popular logic mazes include tilt mazes and other novel designs which usually increase the complexity of the maze, sometimes to the point that the maze has to be designed by a program to eliminate multiple paths. Additional examples include Area mazes or A mazes, which the area of the tile stepped on must alternately increase and decrease with every step. Rolling dice mazes, in which a die is rolled onto cells based on various rules. Number mazes, in which a grid of numbers is navigated by traveling the number shown on the current square. Multi State mazes, in which the rules for navigation change depending on how the maze has been navigated. External links Examples http www.clickmazes.com http www.logicmazes.com http www.mazelog.com Mazelog a collection of original logic mazes of different types. http www.rvvz.demon.nl xor index.html Xor game Category Logic puzzles Category Mazes ... more details
File Domino Logic Gates.svg thumb The two domino logic gates, from which all others can be built. The XOR gate is dependent on timing. A domino computer is a mechanical computer built using dominoes ref name domcom http everything2.com index.pl?node id 1764437 Domino computer ref to represent mechanical Operational amplifier amplification or Logic gate logic gating of digital signal s. Because of the existence of multiple schemes, domino computer will be used in this article as a collective noun, denoting any particular scheme that uses the mentioned base phenomenon of domino sequences for building machines equivalent to a computer. This choice of terminology may be somewhat arbitrary, because only few resources write on this topic. ref name comdomcon http www.pinkandaint.com oldhome comp dominoes index.html Domino computers , a detailed description written by http www.pinkandaint.com David Johnston ref Basic phenomenon Sequences of standing dominoes so that each topples the next one can be arranged to demonstrate digital concepts such as amplifier amplification and digital signal s. It is some digital information that is conducted by a string of dominoes, thus this effect differs from Phenomenon phenomena where energy is conducted without amplification , thus it dissipates or where amplification is applied to non digital signals, thus noise effects occur. The Domino Day event shows many constructs, mainly with purpose of entertainment. Some constructs may remind people of digital circuit s. Some of them suggest that not only telegraph like tools can be shown, but also simple information processing modules can be built. It is possible to use this phenomenon for constructing unconventional computing tools. ref name domcom ref name comdomcon ref name moldom James Maguire http ... synapse s. Logic elements The two logic gates XOR and OR are the easiest to make with dominoes. All other gates can be built from these A XOR 1 and A OR B XOR A XOR B A AND B . The XOR gate shown here ... more details
. XOR tag routing In XOR tag routing, switch settings are based on source PE XOR destination PE . This XOR ... source and destination have in common. The most significant bit of the XOR tag is used to select ..., if PE 001 wishes to send a message to PE 010, the XOR tag will be 011 and the appropriate switch ... more details
of the XOR. Then, the algorithm moves to the right by one byte. So if it were working on bytes 2, 3 ... of rotation and XOR. The rightmost byte of it is used in each iteration to XOR with the rightmost .... Due to the nature of the XOR operation, it is reversible. Analysis of Madryga At a glance, Madryga ... the parity of the ciphertext for any plaintext. Here, parity bit Parity parity refers to the XOR sum ... more details
Unreferenced date November 2008 align right image Data Strobe Encoding.png small Data strobe encoding and recovered clock. small Data strobe encoding or D S encoding is an encoding scheme for transmitting data in digital circuit s. It uses two signal lines e.g. wires in a cable or traces on a printed circuit board , Data and Strobe . These have the property that either Data or Strobe changes its Truth value logical value in one clock cycle , but never both. This allows for easy clock recovery with a good jitter tolerance by XOR ing the two signal line values. There is an equivalent way to specify the relationship between Data and Strobe. For even numbered Data bits, Strobe is the opposite of Data. For odd numbered Data bits, Strobe is the same as Data. From this definition it is more obvious that the XOR of Data and Strobe will yield a clock signal. Also, it specifies the simplest means of generating the Strobe signal for a given Data stream. Data strobe encoding originated in IEEE 1355 Standard and is used on the signal lines in SpaceWire and the FireWire IEEE 1394 also known as FireWire 400 system. Gray code is another code that always changes one logical value, but never more than one. Category Line codes telecomm stub ... more details
Unreferenced date December 2009 In cryptography , residual block termination is a variation of cipher block chaining mode CBC that does not require any Padding cryptography padding . It does this by effectively changing to cipher feedback mode for one block. The cost is the increased complexity. Encryption procedure If the plaintext length N is not a multiple of the block size cryptography block size L Encrypt the N L full blocks of plaintext using the cipher block chaining block cipher modes of operation mode Encrypt the last full encrypted block again XOR the remaining bits of the plaintext with leftmost bits of the re encrypted block. Decryption procedure Decrypt the N L full encrypted blocks using the Cipher Block Chaining mode Encrypt the last full encrypted block XOR the remaining bits of the ciphertext with leftmost bits of the re encrypted block. Proof that this decryption procedure really is the inverse of the encryption procedure is left as an exercise for the reader. Short message For messages shorter than one Block size cryptography block , residual block termination can use an encrypted Initialization vector IV instead of the previously encrypted block. Cryptography navbox block DEFAULTSORT Residual Block Termination Category Cryptographic algorithms ... more details
Image MunchingSquaresAnim.gif thumb Munching squares animation Image munchingsquares.jpg thumb The Munching Square is a display hack dating back to the PDP 1 ca. 1962, reportedly discovered by Jackson Wright , which employs a trivial computation repeatedly plotting the graph Y X XOR T for successive values of T to produce an impressive display of moving and growing squares that devour the screen. The initial value of T is treated as a parameter, which, when well chosen, can produce amazing effects. Some of these, later re discovered on the LISP machine, have been christened munching triangles try AND for XOR and toggling points instead of plotting them , munching w s, and munching mazes. More generally, suppose a graphics program produces an impressive and ever changing display of some basic form, foo , on a display terminal, and does it using a relatively simple program then the program or the resulting display is likely to be referred to as munching foos . References http www.catb.org jargon html M munching squares.html Munching squares entry in the Jargon File . External links http www.computerhistory.org pdp 1 index.php?f showitem&id 25.4&popupwin 1 Video of the original Munching Squares demo running on a PDP 1 http mathworld.wolfram.com MunchingSquares.html Munching Squares at MathWorld Category History of software Category Screensavers Category Novelty software software stub ... more details
orphan date September 2010 Infobox video game title Basketball Challenge collapsible state show image image caption aspect ratio resolution developer XOR Corporation publisher distributor license series engine version released vgrelease genre modes ratings vgratings platforms IBM micros and compatibles media requirements input Basketball Challenge is a computer game developed by the XOR Corporation in 1987 for IBM micros and compatibles. Gameplay The player is the coach of a basketball team, and determines the plays and sets, offense and defense. The basketball players are represented by numbers on the onscreen court, and the coach must learn how to effectively use the team s stars and how to obtain the best performance from the regular players. Basketball Challenge can be played by one or two players, or the computer can also play against a human opponent or run the entire game as both players. ref name Dragon136 Reception The game was reviewed in 1988 in Dragon magazine Dragon 136 by Hartley, Patricia, and Kirk Lesser in The Role of Computers column. The reviewers gave the game 3 out of 5 stars. ref name Dragon136 cite journal title The Role of Computers author Lesser, Hartley, Patricia, and Kirk journal Dragon issue 136 date August 1988 pages 76 81 ref References reflist Category 1987 video games Category Basketball video games basketball videogame stub ... more details
The abbreviation IOR may refer to Institute of Recruiters , a non profit Institute for recruiters and HR professionals Refractive index Index of refraction Istituto per le Opere di Religione Institute for Religious Works , the Vatican Bank Interoperable Object Reference , a reference to a CORBA or RMI IIOP object Inhibition of return , a phenomenon in visual perception International Offshore Rule , an early handicapping system for yacht racing Independent Order of Rechabites inclusive or as opposed to XOR exclusive OR IORgroup Ltd formerly Interiors of Richmond , a London based commercial interior design company I.O.R. , optics company of Romania Interest on Reserves, a term used in macroeconomics having to do with the Federal Reserve System disambig de IOR it IOR ja IOR pl IOR ... more details
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