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Term Description P.P.M. An abbreviation of pages per minute. See speed. Package The material that surrounds the die or chip. The package protects the electronic circuitry. Packet A basic message unit for communication across a network. A packet usually includes routing information, data, and (sometimes) error detection information. Packet Switched Network Network that does not establish a dedicated physical path, but transmits data in segments called packets. Packets are sent over the best available network connection and then reassembled at the end-point. Packet Switching Packet switching technologies are based on end stations collecting data to be transmitted into packets. Packets may be variable in length or may be of a fixed size, as in ATM. Packets may be transmitted at any time without the setup of a connection with the destination. It is up to the network to determine how to route the data to the destination. At the same time the network does not guarantee delivery and it is up to the end stations to provide mechanisms for reliable delivery. Most data communications technologies are based on packet switching. The use of packet switching is driven by the underlying assumption that computer data traffic is inherently bursty in nature, and not time-critical. Packet-switched network A communications network that uses shared facilities to route data packets from and to different users. Unlike a circuit-switched network, a packet-switched network does not set up dedicated circuits for each session. PAL format Phase Alternation Line - the European color television format. See NTSC, SECAM. PALplus PALplus is the name of a strategy group formed in 1989 to develop an enhanced terrestrial transmission system compatible with conventional PAL. The group, made up of German, Austrian, Swiss and British broadcasters as well as Philips, Thomson, Grundig, Nokia, Sony and Samsung, set itself the task of enhancing the PAL signal by developing the 16:9 letterbox format, increasing the useable luminance bandwidth, reducing cross-color artifacts, working on echo cancellation and improving sound. PAN Personal Area Networks Parallel Cable III The Xilinx Parallel Cable III is a download cable connected to the parallel port of the PC. It is used to program Xilinx FPGAs and CPLDs using the JTAG interface. Parallel Interface A communication mechanism used to transfer data from a computer to a printer, several bits at a time. Most parallel interfaces are 8 bits wide, and thus transfer one byte in each transaction, however a few are 16 bits wide, transferring two bytes simultaneously. Parallel Multiplier Type of IP that multiplies all input bits of the multiplier simultaneously. Parallel Port An I/O channel for a parallel device, like a printer. Increasingly, other devices such as removable storage drives, scanners etc. share the printer parallel port using a 'pass through' mechanism. Parameratizable Refers to the ability to change the size of an IP core based on the designer's requirements, e.g. width of bus. Parameters are entered by using the Xilinx CORE Generator. Parking (Bluetooth) Parking is a mechanism that allows a Bluetooth Master to connect to an additional 256 devices. 256 is a hard limit as 8 bits are allocated in Bluetooth for the Parked Member Address (PMA). To Park a device the Bluetooth Master issues a Park command to an Active Slave and assigns it a PMA. This Slave then enters the Parked mode and surrenders its AMA. As a Parked Slave the device will revert to a passive mode and only monitor for commands on an occasional basis. The difference between Standby and Parked however is that the Slave will remain synchronized to the Master's hopping pattern and regularly update its clock offset. Thus this device can be reconnected at any time with a minimum latency. Partial reconfiguration The ability to reprogram a portion of the FPGA. This allows a user to update part of a Xilinx FPGA while the remaining part is being used. Other vendors do not have this feature. Passive Slave State (Bluetooth) Part of a Piconet but in a inactive and low power, but occasionally monitoring and still synchronized state. Pay TV Encrypted TV programs, which can only be accessed by subscribers, using entitled smart cards of the broadcasters. Generally Pay TV is distinguished into two categories: 1. Pay per Channel Customers subscribe on a monthly basis a package of TV channels. 2. Pay Per View Customers pay for viewing one single movie or, e.g. sports event which is selected individually from the TV channels. The smart card registers the access to the program in order to charge the customer for the selected service. PBSRAM PBSRAM stands for Pipeline Burst SRAM. The PBSRAM devices have input and output registers for data, which are not incorporated into the flow-through device. This allows the pipelined device to operate with a much faster cycle time than the flow-through version. PBX Private Branch Exchange, a private telephone network. PC Personal Computer PC100 DRAM A Type of DRAM used to support 100MHz system bus speed. PCF Point Coordination Function PCI Peripheral Component Interconnect. A high-performance, 32-bit or 64-bit bus designed to be used with devices that have high bandwidth requirements, such as the display subsystem. It is a standard interface defined by the computer industry for local bus interconnection between microprocessors and other peripherals in a system (memory controllers, extended bus interfaces, and graphics controllers). PCI SIG The PCI Special Interest Group (SIG) is an unincorporated association of members of the microcomputer industry set up for the purpose of monitoring and enhancing the development of the PCI architecture. The SIG is led by a nine member steering committee and governed by SIG bylaws. PCL Printer Command Language, normally in reference to Hewlett-Packard Printer Command Language (HP PCL), but most manufacturers emulating HP PCL leave out the HP. PCM Pulse Code Modulation. Method of modulation in which analog voice signals are sampled and converted to digital words that are then transmitted serially. Most PCM systems use either 7- or 8-bit binary codes. There are, however, several standards for PCM coding: most common are µ-Law in North America and A-Law in Europe (both based on logarithmic conversion of the signal). Requires sampling the analog signal 8 thousand times per second and converting the sample to an 8-bit value. Hence, PCM requires a 64 Kbps digital channel to carry one voice connection. PCMCIA Personal Computer Memory Card International Association (PCMCIA) PC card. A credit card-size device originally designed as a platform for add-on memory for portable computers, but later expanded to include a wide range of peripherals including pagers and radio modems. PCP Parallel Control Port, used by Motorola for a standard microprocessor bus port. PCS PCs (Personal Communication System) is a new lower power high frequency competitive technology to cellular operating at 1.5 to 1.8 Ghz range. It is usually associated with cordless telephone-like devices and PDA devices. Service is typically digital. PDA PDAs (Personal Digital Assistant) are primarily a productivity and communications tool that is lightweight, compact, durable, reliable, easy to use, and integrates into existing operations. PDAs fall into four categories: Handheld PCs (HPCs), Palm-size PCs (PPCs), Smart phones, Handheld instruments. PDL Page Description Language: a language for describing the layout and contents of a printed page used with laser printers. The best-known PDLs are Adobe PostScript and HP PCL (Printer Control Language). Both PostScript and modern versions of PCL are object-oriented, describing a page in terms of geometrical objects such as lines, arcs, and circles. PDP Plasma display panels Peer-to-peer network A network design in which each PC shares and uses devices on an equal basis. All nodes on the network have equal access to and control of the network medium. Performance Here, the device goes into low power mode consuming minimal amount of current. Excellent for long periods of inactivity or minimal activity. Personal Printer A small printer, typically producing 4 - 5 p.p.m, which is physically compact to allow easy use on a desk, and sufficiently inexpensive to justify if ownership by an individual for their personal printing needs. Phase jitter Abrupt, spurious variations in an analog line, generally caused by power and communication equipment along the line that shifts the signal phase relationship back and forth. Phase Linearity The delay in the output sequence in relation to the input sequence is characterized by a linear relationship. Phase shift Creating a signal that is delayed by some percentage of the clock cycle. PHY, Physical Layer PHYsical layer. The bottom layer of the OSI and ATM protocol stack, which defines the interface between the different physical media. The PHY consists of two sublayers: the transmission convergence (TC) sublayer and the physical medium-dependent (PMD) sublayer. he nuts and bolts layer, where the cable, connector and signaling specifications are defined . The Physical layer transmits the unstructured raw bit stream over a physical medium, and describes the electrical, mechanical, and functional interface to the carrier. It is this layer that provides the linking to the upper sessions via signaling. (Example of this kind of signal interface would be RS-232). Piconets (Bluetooth) Master device with 1 to 7 Active Slave devices PID Packet Identifier. PID is a code used for identifying the components that form a particular service in the transmitted datastream. Piezo-Electric The property of certain crystals that causes them to oscillate when subjected to electrical pressure (voltage). Pigment Inks While conventional inks are essentially oil-based dyes, pigment inks consist of tiny chunks of solid pigment suspended in a liquid solution. According to their proponents, pigment inks offer richer, deeper colors and have less tendency to run, bleed or feather. PIN Personal Identification Number Pixel A "picture cell element", commonly used as a misnomer for a dot in laser printing. It is a misnomer because a laser printer dot is an indivisible unit, whereas a pixel may actually comprise several dots arranged in a matrix to form a shade of gray. Place The process of assigning logic from your design to physical cell locations in the FPGA. The process done prior to routing. Plaintext The original message PLCC Plastic Leaded Chip Carrier package. Type of surface mount device package. PLL Acronym for Phase Locked Loop. An analog circuit used to perform clock management functions on and off-chip. Plug and Play A design philosophy and set of specifications that describe hardware and software changes to the PC and its peripherals that automatically identify and arbitrate resource requirements among all devices and buses on the system. Plug and Play also specifies a set of API elements that are used in addition to (not in place of) existing driver architectures. Plug-In Plug-in is a control networking protocol developed by Intelogis PMA (Bluetooth) Parked Member Address PMD Physical Medium Dependent. A sublayer of the physical layer that interfaces directly with the physical medium and performs the most basic bit transmission functions of the network. PN Pseudo Noise. A digital signal with noise-like properties. PNA Phone Networking Alliance - Home networking standard for 1-10 Mbps over phone wire. Point of Presence (POP) A physical location within a Local Access and Transport Area (LATA) at which an inter-exchange carrier establishes itself for the purpose of obtaining LATA access. Point-to-multipoint A communications channel that runs from one point to several other points. Point-to-Point A (temporary) separate connection between a service provider and one receiver. (E.g. VOD service) POS Point of Sale (Terminal) PostScript A page description language developed by Adobe. Generally used by laser printers, PostScript is becoming increasingly common in high-end ink jets too. POTS Plain Old Telephone Service. It refers to analog telephone service, at nominal 0-3 kHz bandwidth. POTS Splitter A device that rejects the DSL signal and allows the POTS frequencies to pass through. Power It is the time required by the device to go from the normal operating mode to the Power Down Mode. Power Down Mode An operating condition where the device consumes minimal amount of current. Excellent for portable applications. Power Down Time It is the time required by the device to go from the normal operating mode to the Power Down Mode. Power meter A device used to measure radio energy. Power Save Mode - "Sleep" mode Provisions are made in the protocol for the portable stations to go to low power "sleep" mode during a time interval defined by the base station. The client is unable to communicate, but the sleep mode consumer less power. PPP Point-to-Point Protocol. A data link protocol developed by the Internet Engineering Task Force for dialup telephone connections, such as between a computer and the Internet PPV Pay Per View. Customers pay for viewing one single movie or, e.g. sports event which is selected individually from the TV channels. The smart card registers the access to the program in order to charge the customer for the selected service. Preamble Symbols at the beginning of the frame that support robust carrier sensing & collision detection, equalizer training, timing recovery & gain adjustment. Presentation Normalizing data syntax between applications Presentation layer The Presentation Layer formats the data to be presented to the Application Layer. It can be viewed as the translator for the network. The Presentation Layer provides a common representation for data that can be used between application processes. It includes: Encoding data, Compressing data to reduce the number of bits transmitted, Encrypting data for privacy and authentication. PRI (Primary Rate Interface) Primary Rate ISDN service is targeted at larger corporate customers. PRI service consists of 23 B channels in North America and is transported across a standard T1 physical layer interface. In Europe the service provides 30 B channels plus one 64 Kbps D channel and uses an E1 physical layer. PRI requires two sets of twisted pair telephone lines. Print Cartridge A print cartridge is a printer consumable which normally contains all the major replaceable elements in a laser printer, such as toner, and developer. Print Engine The mechanism which transcribes a bitmap created by the printer controller into a printed image. Printer Controller The dedicated computer in a printer which receives data to be printed from a computer, along with commands defining how the data should be formatted, and uses these to create (rasterize) a bitmap describing the image required on the paper which is then passed to the print engine for transcription to the paper. Printer Dot The individual pixel in a halftone image. The size of a printer dot is variable, ranging from zero (all white) to the size of the halftone screen (all black). Printer Driver A software utility incorporated into a software application package on a computer which enables the application to determine the commands required by the printer to format data for printing, and which provides the application with information about the facilities provided by the printer. Private Key The privately held decryption key. It is unknown to the public and difficult to determine mathematically. PRNG Pseudo Random Number Generator Production Printer A large heavy-duty printer designed for almost continuous printing in a production environment, either for large quantities of small documents such as invoices and account statements, or for small quantities of large documents such as reports, short-run books, newsletters etc. Program A concatenation of one or more events under the control of a broadcaster, e.g. news show, entertainment show. Programming Process of storing data into memory devices, e.g. EPROM, EEPROM, or FLASH, often used for configuration of FPGA's. Sometimes used synonymously as configuration. PROM Acronym for Programmable Read Only Memory. A device that is typically used to hold data to configure (program) FPGAs. Propogation The travel of a signal through a medium such as air or free space. Protocol Data Unit (PDU) A discrete piece of information such as a packet or frame. It is in the appropriate format to be segmented and encapsulated in the payload of an ATM cell. Protocols, Communications Protocols A set of rules or standards designed to enable computers to connect with one another and to exchange information with as little error as possible. These rules are set for communicating, particularly for the format and transmission of data. PSI Abbreviation for Program Specific Information. PSTN Public Switched Telephone Network. It is a Wide Area Network (WAN) that is available to all users in a region, which compares to private networks that are owned or leased by individual companies or subscribers. In some regions of the world, the PSTN is operated by government entities, while in others they are operated by public utility companies. The PSTN is evolving now into the global Public Switched Network (PSN) to carry not only voice traffic, but data and video traffic as well. Public Key The publicly known key associated with a given person's use of a public key cryptographic system. The public key is used for encryption. Public Key Certificates A statement, possibly on paper, but more often transmitted electronically over an information network, that establishes the relationship between a named individual or organization and a specified public key, and is signed (digitally) by a trusted authority. Public Key Cryptography An encryption method that is asymmetric, i.e., separate keys are used for the encryption and decryption functions. Public Switched Network (PSN) The pre-Divestiture nationwide network maintained by AT&T and the independent telephone companies which provides nationwide, unrestricted telephone service. Pull-Down It is the amount of current needed by an inactive device connected to the power supply. Pull-Up In this state, there is no signal activity within the device. The inputs and outputs are not transitioning and the power required is only due to static current. Pulse Code Modulation (PCM) The form of modulation in which the information signals are sampled at regular intervals and a series of pulses in coded form are transmitted representing the amplitude of the information signal at that time. Push Button Compilation Design flow that is easy to use. Operates at the "push of a button."   A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z