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Galeb (computer)
Galeb () was an 8-bit computer developed by the PEL Varaždin company in Yugoslavia in the early 1980s. A grand total of 250 were produced by the end of the summer of 1984, before being replaced with the Orao. Galeb was designed by Miroslav Kocjan and inspired by Compukit UK101, Ohio Scientific Superboard and Superboard II computers. These machines appeared in the UK and USA in 1979 and were less expensive than Apple II, Commodore PET and/or TRS-80 computers. Galeb's codename YU 101 was chosen to resemble Compukit's UK101. Galeb was very similar to computers that inspired it: Specifications: * Central processing unit, CPU: MOS Technology 6502 * ROM: 16 KB (with modified Microsoft BASIC interpreter and Machine code monitor) * RAM: 9 KB (expandable to 64 KB) * Keyboard: 59-key QWERTZ * I/O ports: composite video and RF TV out, cassette tape interface ( DIN-5), RS-232 (D-25), edge expansion connector * Sound: Internal speaker; single-channel, 5 octaves * Graphics: monochrom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Computer
A personal computer, commonly referred to as PC or computer, is a computer designed for individual use. It is typically used for tasks such as Word processor, word processing, web browser, internet browsing, email, multimedia playback, and PC game, gaming. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or technician. Unlike large, costly minicomputers and mainframes, time-sharing by many people at the same time is not used with personal computers. The term home computer has also been used, primarily in the late 1970s and 1980s. The advent of personal computers and the concurrent Digital Revolution have significantly affected the lives of people. Institutional or corporate computer owners in the 1960s had to write their own programs to do any useful work with computers. While personal computer users may develop their applications, usually these systems run commercial software, free-of-charge software ("freeware"), which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRS-80
The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer developed by American company Tandy Corporation and sold through their Radio Shack stores. Launched in 1977, it is one of the earliest mass-produced and mass-marketed retail home computers. The name is an abbreviation of ''Tandy Radio Shack, Z80 [microprocessor]'', referring to its Zilog Z80 8-bit microprocessor. The TRS-80 has a full-stroke QWERTY keyboard, 4 kilobyte, KB dynamic random-access memory (DRAM) standard memory, small size and desk area, floating-point Level I BASIC language Interpreter (computing), interpreter in read-only memory (ROM), 64-character-per-line computer monitor, video monitor, and had a starting price of US$600 (equivalent to US$ in ). A cassette tape drive for program storage was included in the original package. While the software environment was stable, the cassette load/save process combined with keyboard bounce issues ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassette Tape
The Compact Cassette, also commonly called a cassette tape, audio cassette, or simply tape or cassette, is an analog audio, analog magnetic tape recording format for Sound recording and reproduction, audio recording and playback. Invented by Lou Ottens and his team at the Netherlands, Dutch company Philips, the Compact Cassette was released in August 1963. Compact Cassettes come in two forms, either containing content as a prerecorded cassette (''Musicassette''), or as a fully recordable "blank" cassette. Both forms have two sides and are reversible by the user. Although List of magnetic tape cartridges and cassettes, other tape cassette formats have also existed—for example the Microcassette—the generic term ''cassette tape'' is normally used to refer to the Compact Cassette because of its ubiquity. From 1983 to 1991 the cassette tape was the most popular Timeline of audio formats, audio format for new Record sales, music sales in the United States. Compact Cassettes con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TV Out
The term TV-out is commonly used to label the connector of equipment providing an analog video signal acceptable for a television AV input. TV-out is different from AV-out in that it only provides video, no audio. Types of signals and their respective connectors include: *Composite video *S-video *Component video Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compo ... On a PC the TV-out typically requires a driver that supports the chipset controlling the usage of the output. See AV input for more information. References Television technology Graphics cards {{Compu-hardware-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Frequency
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper limit of audio frequencies that humans can hear (though these are not electromagnetic) and the lower limit of infrared frequencies, and also encompasses the microwave range. These are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves, so they are used in radio technology, among other uses. Different sources specify different upper and lower bounds for the frequency range. Electric current Electric currents that oscillate at radio frequencies (RF currents) have special properties not shared by direct current or lower audio frequency alternating current, such as the 50 or 60 Hz current used in electrical power distribution. * Energy from RF currents in conduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Video
Composite video, also known as CVBS (composite video baseband signal or color, video, blanking and sync), is an analog video format that combines image information—such as brightness (luminance), color (chrominance), and synchronization, into a single signal transmitted over one channel. It is most commonly used for standard-definition television, and is sometimes referred to as ''SD video''. The signal is typically carried on a yellow RCA connector, with separate connectors used for left and right audio channels. In professional equipment, a BNC connector is often used instead. Other connector types may appear in compact consumer devices like digital cameras. Composite video supports several line resolutions, including 405-line, 525-line, and 625-line interlaced formats. It exists in three major regional variants based on analog color encoding standards: NTSC, PAL, and SECAM. The same format can also be used to transmit monochrome (black-and-white) video. Signal comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory-mapped I/O And Port-mapped I/O
Memory-mapped I/O (MMIO) and port-mapped I/O (PMIO) are two complementary methods of performing input/output (I/O) between the central processing unit (CPU) and peripheral devices in a computer (often mediating access via chipset). An alternative approach is using dedicated I/O processors, commonly known as channels on mainframe computers, which execute their own instructions. Memory-mapped I/O uses the same address space to address both main memory and I/O devices. The memory and registers of the I/O devices are mapped to (associated with) address values, so a memory address may refer to either a portion of physical RAM or to memory and registers of the I/O device. Thus, the CPU instructions used to access the memory (e.g. ) can also be used for accessing devices. Each I/O device either monitors the CPU's address bus and responds to any CPU access of an address assigned to that device, connecting the system bus to the desired device's hardware register, or uses a dedicated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QWERTZ
The QWERTZ ( ) QWERTZU ( ), or QWERTZUIOP keyboard is a typewriter and keyboard layout widely used in Central and Southeast Europe. The name comes from the first six letters at the top left of the keyboard: ( ). Overview The main difference between QWERTZ and QWERTY is that the positions of the and keys are switched (hence the nickname "kezboard"). This change possibly was made for three major reasons: * is a much more common letter than in German; the latter appears only in loanwords (mainly from Ancient Greek) and in proper names such as Meyer (alongside Meier and various other variants). * and often appear next to each other in the German orthography, and typewriter jamming would be reduced by placing the two keys so they could be typed with separate hands. * and are also next to each other. , meaning "to" in German, and also a very common prefix can also be written very easily. Similar to many other non-English keyboards: * Part of the keyboard is adapted to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Keyboard
A computer keyboard is a built-in or peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or Push-button, keys to act as Mechanical keyboard, mechanical levers or Electronic switching system, electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input device, input method for computers since the 1970s, supplemented by the computer mouse since the 1980s, and the touchscreen since the 2000s. Keyboard keys (buttons) typically have a set of characters Engraving, engraved or Printing, printed on them, and each press of a key typically corresponds to a single written symbol. However, producing some symbols may require pressing and holding several keys simultaneously or in sequence. While most keys produce character (computing), characters (Letter (alphabet), letters, Numerical digit, numbers or symbols), other keys (such as the escape key) can prompt the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random-access Memory
Random-access memory (RAM; ) is a form of Computer memory, electronic computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A random-access memory device allows data items to be read (computer), read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks and Magnetic tape data storage, magnetic tape), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement. In today's technology, random-access memory takes the form of integrated circuit (IC) chips with MOSFET, MOS (metal–oxide–semiconductor) Memory cell (computing), memory cells. RAM is normally associated with Volatile memory, volatile types of memory where s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machine Code Monitor
A machine code monitor ( machine language monitor) is software that allows a user to enter commands to view and change memory address, memory locations on a computer, with options to load and save memory contents from/to secondary storage. Some full-featured machine code monitors provide detailed control ("single-stepping") of the execution of machine language programs (much like a debugger), and include absolute-address Assembly language#Assembler, code assembly and disassembler, disassembly capabilities. Motorola published the MIKBUG ROM monitor for the 6800 in 1973 and the BUFFALO ROM monitor for the Motorola 68HC11, 68HC11. Machine code monitors became popular during the home computer era of the 1970s and 1980s and were sometimes available as resident firmware in some computers (e.g., the built-in monitors in the Commodore 128, Zenith Z-89, Heathkit H89 and Zenith laptops). Often, computer manufacturers rely on their ROM-resident monitors to permit users to reconfigure their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interpreter (computing)
In computer science, an interpreter is a computer program that directly executes instructions written in a programming or scripting language, without requiring them previously to have been compiled into a machine language program. An interpreter generally uses one of the following strategies for program execution: # Parse the source code and perform its behavior directly; # Translate source code into some efficient intermediate representation or object code and immediately execute that; # Explicitly execute stored precompiled bytecode made by a compiler and matched with the interpreter's virtual machine. Early versions of Lisp programming language and minicomputer and microcomputer BASIC dialects would be examples of the first type. Perl, Raku, Python, MATLAB, and Ruby are examples of the second, while UCSD Pascal is an example of the third type. Source programs are compiled ahead of time and stored as machine independent code, which is then linked at run-ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
