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55-408: S/PDIF ( Sony/Philips Digital Interface ) is a type of digital audio interface used in consumer audio equipment to output audio over relatively short distances. The signal is transmitted over either a coaxial cable using RCA or BNC connectors, or a fibre-optic cable using TOSLINK connectors. S/PDIF interconnects components in home theaters and other digital high-fidelity systems. S/PDIF

110-404: A power of two multiple of the unit of address resolution (byte or word). Converting the index of an item in an array into the memory address offset of the item then requires only a shift operation rather than a multiplication. In some cases this relationship can also avoid the use of division operations. As a result, most modern computer designs have word sizes (and other operand sizes) that are

165-402: A component breakout cable and an S-Video cable. The Digital Visual Interface (DVI) is a video interface standard designed to maximize the visual quality of digital display devices such as flat panel LCD computer displays and digital projectors. It is designed for carrying uncompressed digital video data to a display. There are four basic connectors: The connector also includes provision for

220-754: A computer and its display monitor, or a computer and a home-theater system. The video signal is not compatible with DVI or HDMI , but a DisplayPort connector can pass these signals through. DisplayPort is a competitor to the HDMI connector, the de facto digital connection for high-definition consumer electronics devices. Audio connectors are used for audio frequencies. They can be analog or digital . Single-wire connectors used frequently for analog audio include: Multi-conductor connectors: Digital audio interfaces and interconnects: A phone connector (tip, ring, sleeve) also called an audio jack, phone plug, jack plug, stereo plug, mini-jack, or mini-stereo. This includes

275-426: A computer architecture is designed, the choice of a word size is of substantial importance. There are design considerations which encourage particular bit-group sizes for particular uses (e.g. for addresses), and these considerations point to different sizes for different uses. However, considerations of economy in design strongly push for one size, or a very few sizes related by multiples or fractions (submultiples) to

330-483: A count field, by a delimiting character, or by an additional bit called, e.g., flag, or word mark . Such machines often use binary-coded decimal in 4-bit digits, or in 6-bit characters, for numbers. This class of machines includes the IBM 702 , IBM 705 , IBM 7080 , IBM 7010 , UNIVAC 1050 , IBM 1401 , IBM 1620 , and RCA 301. Most of these machines work on one unit of memory at a time and since each instruction or datum

385-537: A family of multi-pin electrical connectors used in a variety of applications. Mini-DIN is similar to the larger, older DIN connector . Both are standards of the Deutsches Institut für Normung, the German standards body. D-subminiature or D-sub is a common type of electrical connector used particularly in computers. Calling them "sub-miniature" was appropriate when they were first introduced, but today they are among

440-463: A floating point instruction can only address words while an integer arithmetic instruction can specify a field length of 1-64 bits, a byte size of 1-8 bits and an accumulator offset of 0-127 bits. In a byte-addressable machine with storage-to-storage (SS) instructions, there are typically move instructions to copy one or multiple bytes from one arbitrary location to another. In a byte-oriented ( byte-addressable ) machine without SS instructions, moving

495-451: A fresh design has to coexist as an alternative size to the original word size in a backward compatible design. The original word size remains available in future designs, forming the basis of a size family. In the mid-1970s, DEC designed the VAX to be a 32-bit successor of the 16-bit PDP-11 . They used word for a 16-bit quantity, while longword referred to a 32-bit quantity; this terminology

550-404: A power of two times the size of a byte. As computer designs have grown more complex, the central importance of a single word size to an architecture has decreased. Although more capable hardware can use a wider variety of sizes of data, market forces exert pressure to maintain backward compatibility while extending processor capability. As a result, what might have been the central word size in

605-401: A primary size. That preferred size becomes the word size of the architecture. Character size was in the past (pre-variable-sized character encoding ) one of the influences on unit of address resolution and the choice of word size. Before the mid-1960s, characters were most often stored in six bits; this allowed no more than 64 characters, so the alphabet was limited to upper case. Since it

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660-484: A projector or monitor cannot handle a newer codec). Word (data type) In computing , a word is the natural unit of data used by a particular processor design. A word is a fixed-sized datum handled as a unit by the instruction set or the hardware of the processor. The number of bits or digits in a word (the word size , word width , or word length ) is an important characteristic of any specific processor design or computer architecture . The size of

715-417: A second data link for high resolution displays, though many devices do not implement this. In those that do, the connector is sometimes referred to as DVI-DL (dual link). So we need to know two things about the connector: For computers: There are exceptions to the above: Older sound cards had no common standard color codes until after PC 99 . The PC System Design Guide (also known as

770-685: A shorter word (16 or 32 bits) may be used in contexts where the range of a wider word is not needed (especially where this can save considerable stack space or cache memory space). For example, Microsoft's Windows API maintains the programming language definition of WORD as 16 bits, despite the fact that the API may be used on a 32- or 64-bit x86 processor, where the standard word size would be 32 or 64 bits, respectively. Data structures containing such different sized words refer to them as: A similar phenomenon has developed in Intel's x86 assembly language – because of

825-495: A single byte from one arbitrary location to another is typically: Individual bytes can be accessed on a word-oriented machine in one of two ways. Bytes can be manipulated by a combination of shift and mask operations in registers. Moving a single byte from one arbitrary location to another may require the equivalent of the following: Alternatively many word-oriented machines implement byte operations with instructions using special byte pointers in registers or memory. For example,

880-435: A variable number of cycles, depending on the size of the operands. The memory model of an architecture is strongly influenced by the word size. In particular, the resolution of a memory address, that is, the smallest unit that can be designated by an address, has often been chosen to be the word. In this approach, the word-addressable machine approach, address values which differ by one designate adjacent memory words. This

935-425: A word is reflected in many aspects of a computer's structure and operation; the majority of the registers in a processor are usually word-sized and the largest datum that can be transferred to and from the working memory in a single operation is a word in many (not all) architectures. The largest possible address size, used to designate a location in memory, is typically a hardware word (here, "hardware word" means

990-638: Is a graphics card port which enables some video cards to have bidirectional (input and output) video transfer through a Mini-DIN , usually of the 9-pin variety, and a specialised splitter cable (which can sometimes also transfer sound). VIVO is found predominantly on high-end ATI video cards, although a few high-end NVIDIA video cards also have this port. VIVO on these graphics cards typically supports Composite , S-Video , and Component as outputs, and composite and S-Video as inputs. Many other video cards only support component and/or S-Video outputs to complement Video Graphics Array or DVI , typically using

1045-686: Is a standardized optical fiber connection system. XLR connector plugs and sockets are used mostly in professional audio and video electronics cabling applications. XLR connector are also known as Cannon plugs after their original manufacturer. They are used for analog or digital balanced audio with a balanced line Digital audio interfaces and interconnects with the AES/EBU interface also normally use an XLR connector. RCA connectors , also known as phono connectors or phono plugs , are used for analog or digital audio or analog video. These were first used inside pre–World War II radio-phonographs to connect

1100-483: Is able to host several signals on the same wire, with the data delivered and shown on the destination set. It is also fully bi-directional, with its full bandwidth used in one direction or the other, or split directions up to its maximum. DisplayPort is a digital display interface standard (approved May 2006, current version 1.4 published on March 1, 2016). It defines a new license-free, royalty-free, digital audio/video interconnect, intended to be used primarily between

1155-455: Is also known as Sony/Philips Digital Interface. Sony and Philips were the primary designers of S/PDIF. S/PDIF is standardized in IEC 60958 as IEC 60958 type II (IEC 958 before 1998). A common use is to carry two channels of uncompressed digital audio from a CD player to an amplifying receiver. The S/PDIF interface is also used to carry compressed digital audio for surround sound as defined by

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1210-501: Is based on the AES3 interconnect standard . S/PDIF can carry two channels of uncompressed PCM audio or compressed 5.1 surround sound ; it cannot support lossless surround formats that require greater bandwidth . S/PDIF is a data link layer protocol as well as a set of physical layer specifications for carrying digital audio signals over either optical or electrical cable. The name stands for Sony/Philips Digital Interconnect Format but

1265-476: Is efficient in time and space to have the word size be a multiple of the character size, word sizes in this period were usually multiples of 6 bits (in binary machines). A common choice then was the 36-bit word , which is also a good size for the numeric properties of a floating point format. After the introduction of the IBM System/360 design, which uses eight-bit characters and supports lower-case letters,

1320-446: Is identical between the two channels and is divided into 12 words of 16 bits each, with the first 16 bits being a control code. S/PDIF is meant to be used for transmitting 20-bit audio data streams plus other related information. S/PDIF can also transport 24-bit samples by way of four extra bits; however, not all equipment supports this, and these extra bits may be ignored. To transmit sources with less than 20 bits of sample accuracy,

1375-405: Is natural in machines which deal almost always in word (or multiple-word) units, and has the advantage of allowing instructions to use minimally sized fields to contain addresses, which can permit a smaller instruction size or a larger variety of instructions. When byte processing is to be a significant part of the workload, it is usually more advantageous to use the byte , rather than the word, as

1430-456: Is several units long, each instruction takes several cycles just to access memory. These machines are often quite slow because of this. For example, instruction fetches on an IBM 1620 Model I take 8 cycles (160 μs) just to read the 12 digits of the instruction (the Model II reduced this to 6 cycles, or 4 cycles if the instruction did not need both address fields). Instruction execution takes

1485-525: Is the x86 family, of which processors of three different word lengths (16-bit, later 32- and 64-bit) have been released, while word continues to designate a 16-bit quantity. As software is routinely ported from one word-length to the next, some APIs and documentation define or refer to an older (and thus shorter) word-length than the full word length on the CPU that software may be compiled for. Also, similar to how bytes are used for small numbers in many programs,

1540-510: Is the 64-bit member of that architecture family, continues to refer to 16-bit halfword s, 32-bit word s, and 64-bit doubleword s, and additionally features 128-bit quadword s. In general, new processors must use the same data word lengths and virtual address widths as an older processor to have binary compatibility with that older processor. Often carefully written source code – written with source-code compatibility and software portability in mind – can be recompiled to run on

1595-461: Is the same as the terminology used for the PDP-11. This was in contrast to earlier machines, where the natural unit of addressing memory would be called a word , while a quantity that is one half a word would be called a halfword . In fitting with this scheme, a VAX quadword is 64 bits. They continued this 16-bit word/32-bit longword/64-bit quadword terminology with the 64-bit Alpha . Another example

1650-537: Is used to transmit digital signals in a number of formats, the most common being the 48 kHz sample rate format (used in Digital Audio Tape ) and the 44.1 kHz format, used in CD audio . In order to support both sample rates, as well as others that might be needed, the format has no defined bit rate . Instead, the data is sent using biphase mark code , which has either one or two transitions for every bit, allowing

1705-406: The IEC 61937 standard. This mode is used to connect the output of a Blu-ray , DVD player or computer, via optical or coax, to a home theatre amplifying receiver that supports Dolby Digital or DTS Digital Surround decoding. S/PDIF was developed at the same time as the main standard, AES3, used to interconnect professional audio equipment in the professional audio field. This resulted from

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1760-498: The PDP-10 byte pointer contained the size of the byte in bits (allowing different-sized bytes to be accessed), the bit position of the byte within the word, and the word address of the data. Instructions could automatically adjust the pointer to the next byte on, for example, load and deposit (store) operations. Different amounts of memory are used to store data values with different degrees of precision. The commonly used sizes are usually

1815-426: The 36-bit word being especially common on mainframe computers . The introduction of ASCII led to the move to systems with word lengths that were a multiple of 8-bits, with 16-bit machines being popular in the 1970s before the move to modern processors with 32 or 64 bits. Special-purpose designs like digital signal processors , may have any word length from 4 to 80 bits. The size of a word can sometimes differ from

1870-473: The DVI connector. This means that in some cases not all components with physically compatible connectors will actually work together. Analog A/V connectors often use shielded cables to inhibit radio frequency interference (RFI) and noise . Several generic digital data connection standards are designed to carry audio/video data along with other data and power: Some digital connection standards were designed from

1925-496: The HDMI 1.0 specification. Type C was defined by the HDMI 1.3 specification. Type A is electrically compatible with single link DVI-D. Type B is electrically compatible with dual link DVI-D but has not yet been used in any products. IEEE 1394 (branded "FireWire") is a digital data transfer protocol commonly used for digital cameras (common on MiniDV tape camcorders), but also used for computer data and audio data transfers. Unlike Point-to-Point connections listed above, IEEE 1394

1980-539: The PC ;97, PC 98, PC 99, or PC 2001 specification) is a series of hardware design requirements and recommendations for IBM PC compatible personal computers, compiled by Microsoft and Intel Corporation during 1997–2001. PC 99 introduced a color code for the various standard types of plugs and connectors used on PCs. The color codes for audio plugs follow: Newer connectors are identified by their shape and not their colour. For efficiency and simplicity,

2035-400: The beginning to primarily carry audio and video signals simultaneously: Many analog connectors carry both: S/PDIF is an audio-only format carried over electrical coaxial cable (with RCA jacks ) or optical fibre ( TOSLINK ). Note that there are no differences in the signals transmitted over optical or coaxial S/PDIF connectors—both carry exactly the same information. Selection of one over

2090-996: The desire of the various stakeholders to have at least sufficient similarities between the two interfaces to allow the use of the same, or very similar, designs for interfacing ICs . S/PDIF is nearly identical at the protocol level, but uses either coaxial cable (with RCA connectors ) or optical fibre ( TOSLINK ; i.e., JIS F05 or EIAJ optical), both of which cost less than the XLR connection used by AES3. The RCA connectors are typically colour-coded orange to differentiate from other RCA connector uses such as composite video . S/PDIF uses 75 Ω coaxial cable while AES3 uses 110  Ω balanced twisted pair . Signals transmitted over consumer-grade TOSLINK connections are identical in content to those transmitted over coaxial connectors. Optical provides electrical isolation that can help address ground loop issues in systems. The electrical connection can be more robust and supports longer connections. S/PDIF

2145-432: The electrical or optical equipment include the types and numbers of wires required, voltages, frequencies, optical intensity, and the physical design of the connectors. Any data link layer details define how application data is encapsulated (for example for synchronization or error-correction ). Application layer details define the actual audio or video format being transmitted, often incorporating codecs not specific to

2200-416: The expected due to backward compatibility with earlier computers. If multiple compatible variations or a family of processors share a common architecture and instruction set but differ in their word sizes, their documentation and software may become notationally complex to accommodate the difference (see Size families below). Depending on how a computer is organized, word-size units may be used for: When

2255-651: The full-sized natural word of the processor, as opposed to any other definition used). Documentation for older computers with fixed word size commonly states memory sizes in words rather than bytes or characters. The documentation sometimes uses metric prefixes correctly, sometimes with rounding, e.g., 65 kilowords (kW) meaning for 65536 words, and sometimes uses them incorrectly, with kilowords (kW) meaning 1024 words (2 ) and megawords (MW) meaning 1,048,576 words (2 ). With standardization on 8-bit bytes and byte addressability, stating memory sizes in bytes, kilobytes, and megabytes with powers of 1024 rather than 1000 has become

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2310-490: The interface, such as PCM , MPEG-2 , or the DTS Coherent Acoustics codec . In some cases, the application layer is left open; for example, HDMI contains an Ethernet channel for general data transmission. Some types of connectors are used by multiple hardware interfaces; for example, RCA connectors are used both by the composite video and component video interfaces, but DVI is the only interface that uses

2365-437: The largest common connectors used in computers. The DB25 is used for multi-track recording and other multi-channel audio, analog or digital ( ADAT interface (DB25)), and was the standard connector for IBM compatible PC printer connection before USB and other connections became popular. It offered 8 simultaneous data pathways to the printer. Video In Video Out , usually seen as the acronym VIVO (commonly pronounced vee-voh),

2420-402: The norm, although there is some use of the IEC binary prefixes . Several of the earliest computers (and a few modern as well) use binary-coded decimal rather than plain binary , typically having a word size of 10 or 12 decimal digits, and some early decimal computers have no fixed word length at all. Early binary systems tended to use word lengths that were some multiple of 6-bits, with

2475-399: The original word clock to be extracted from the signal itself. S/PDIF protocol differs from AES3 only in the channel status bits; see AES3 § Protocol for the high-level view. Both protocols group 192 samples into an audio block, and transmit one channel status bit per sample, providing one 192-bit channel status word per channel per audio block. For S/PDIF, the 192-bit status word

2530-495: The original 6.35 mm (quarter inch) jack and the more recent 3.5 mm (miniature or 1/8 inch) and 2.5 mm (subminiature) jacks, both mono and stereo versions. There also exists 4.4 mm Pentaconn connectors . A DIN connector is a connector that was originally standardized by the Deutsches Institut für Normung (DIN). Mini-DIN is a variation. The BNC connector is a very common type of RF connector used for terminating coaxial cable. TOSLINK or Optical Cable

2585-526: The other rests mainly on the availability of appropriate connectors on the chosen equipment and the preference and convenience of the user. Connections longer than 6 meters or so, or those requiring tight bends, should use coaxial cable, since the high light signal attenuation of TOSLINK cables limits its effective range. High-Definition Multimedia Interface (HDMI) is a compact audio/video standard for transmitting uncompressed digital data. There are three HDMI connector types. Type A and Type B were defined by

2640-457: The same codec or signal convention is used by the storage medium. For example, VHS tapes can store a magnetic representation of an NTSC signal, and the specification for Blu-ray Discs incorporates PCM, MPEG-2, and DTS. Some playback devices can re-encode audio or video so that the format used for storage does not have to be the same as the format transmitted over the A/V interface (which is helpful if

2695-536: The source clock. Many S/PDIF implementations cannot fully decouple the final signal from influence of the source or the interconnect. Specifically, the process of clock recovery used to synchronize reception may produce jitter . If the DAC does not have a stable clock reference then noise will be introduced into the resulting analog signal. However, receivers can implement various strategies that limit this influence. Digital audio interface Physical characteristics of

2750-426: The standard size of a character (or more accurately, a byte ) becomes eight bits. Word sizes thereafter are naturally multiples of eight bits, with 16, 32, and 64 bits being commonly used. Early machine designs included some that used what is often termed a variable word length . In this type of organization, an operand has no fixed length. Depending on the machine and the instruction, the length might be denoted by

2805-440: The superfluous bits will be set to zero, and the 4:1–3 bits (sample length) are set accordingly. IEC 61937 defines a way to transmit compressed, multi-channel data over S/PDIF. A number of encodings are available over IEC 61937, including Dolby AC-3 / E-AC-3 , Dolby TrueHD , MP3, AAC, ATRAC , DTS , and WMA Pro . The receiver does not control the data rate, so it must avoid bit slip by synchronizing its reception with

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2860-584: The support for various sizes (and backward compatibility) in the instruction set, some instruction mnemonics carry "d" or "q" identifiers denoting "double-", "quad-" or "double-quad-", which are in terms of the architecture's original 16-bit word size. An example with a different word size is the IBM System/360 family. In the System/360 architecture , System/370 architecture and System/390 architecture, there are 8-bit byte s, 16-bit halfword s, 32-bit word s and 64-bit doubleword s. The z/Architecture , which

2915-594: The turntable pickup to the radio chassis. They were not intended to be disconnected and reconnected frequently, and their retaining friction was quite sufficient for their original purpose. Furthermore, the design of both cable and chassis connectors was for minimum cost. Initially intended for audio-frequency connections only, the RCA plug was also used for analog composite video and non-critical radio-frequency applications. Video connectors carry only video signals. Common video-only connectors include: The Mini-DIN connectors are

2970-438: The unit of address resolution. Address values which differ by one designate adjacent bytes in memory. This allows an arbitrary character within a character string to be addressed straightforwardly. A word can still be addressed, but the address to be used requires a few more bits than the word-resolution alternative. The word size needs to be an integer multiple of the character size in this organization. This addressing approach

3025-454: Was used in the IBM 360, and has been the most common approach in machines designed since then. When the workload involves processing fields of different sizes, it can be advantageous to address to the bit. Machines with bit addressing may have some instructions that use a programmer-defined byte size and other instructions that operate on fixed data sizes. As an example, on the IBM 7030 ("Stretch"),

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