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Galeb (computer)
Galeb (en. ''Seagull'') 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 by Orao. Galeb was designed by Miroslav Kocijan and inspired by Compukit UK101 and Ohio Scientific Superboard and Superboard II computers that appeared in the UK and USA in 1979 and were less expensive than Apple II, Commodore PET and/or TRS-80 computers. The code name YU101 was chosen to resemble Compukit's UK101. Galeb was very similar to computers that inspired it: Specifications: * CPU: MOS Technology 6502 * ROM : 16 KB (with 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 : single-channel, 5 octaves * Graphics: monochrome, 96x48 pixels * Text mode: 16 lines with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Computer
A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. 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. Primarily in the late 1970s and 1980s, the term home computer was also used. Institutional or corporate computer owners in the 1960s had to write their own programs to do any useful work with the machines. While personal computer users may develop their own applications, usually these systems run commercial software, free-of-charge software (" freeware"), which is most often proprietary, or free and open-source software, which is provided in "ready-to-run", or binary, form. Software for personal computers is typically developed and distributed independently from the hardware or operating system ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore PET
The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor, and, in early models, a cassette deck. Development of the system began in 1976, and a prototype was demonstrated at the January 1977 Consumer Electronics Show. The name "PET" was suggested by Andre Souson after he saw the Pet Rock in Los Gatos, and stated they were going to make the "pet computer". It was backronymed to Personal Electronic Transactor. A series of problems delayed production versions until December 1977, by which time the TRS-80 and Apple II had already begun deliveries. ''Byte'' referred to the three machines collectively as the "1977 trinity". Following the initial PET 2001, the design was updated through a series of models with more memory, better keyboard, larger screen, and other modifications. The systems were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassette Tape
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, 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 in 1963, Compact Cassettes come in two forms, either already 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 always used to refer to the Compact Cassette because of its ubiquity. Its uses have ranged from Personal stereo, portable audio to home recording to data storage for early microcomputers; the Compact Cassette technology was originally ... [...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 See AV input AV input is a common label on a connector to receive (AV) audio/visual signals from electronic equipment that generates AV signals (AV output). These terminals are commonly found on such equipment as a television, DVD recorder or VHS recorder, a ... for more information. 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 and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. 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 conductors can radiate into space as electromagnetic waves ( radio waves). This is the basis of radio technology. * RF current does not penetrate deeply into electrica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Video
Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channels) and the even higher-quality component video (three or more channels). In all of these video formats, audio is carried on a separate connection. Composite video is also known by the initials CVBS for composite video baseband signal or color, video, blanking and sync, or is simply referred to as ''SD video'' for the standard-definition television signal it conveys. There are three dominant variants of composite video signals, corresponding to the analog color system used: NTSC, PAL, and SECAM. Usually composite video is carried by a yellow RCA connector, but other connections are used in professional settings. Signal components A composite video signal combines, on one wire, the video information required to recreate a color pic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
I/O Port
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. 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 instead to memory and registers of the I/O device. Thus, the CPU instructions used to access the memory can also be used for accessing devices. Each I/O device monitors the CPU's address bus and responds to any CPU access of an address assigned to that device, connecting the data bus to the desired device's hardware register. To accommodate the I/O devices, some areas of the address bus us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QWERTZ
The QWERTZ or QWERTZU keyboard is a typewriter and keyboard layout widely used in Central 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 was made for three major reasons: * is a much more common letter than in German; the latter rarely appears outside words whose spellings reflect either their importation from a foreign language or the Hellenization of an older German form under the influence of Ludwig I of Bavaria. * 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 key ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Memory
Computer data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers. The central processing unit (CPU) of a computer is what manipulates data by performing computations. In practice, almost all computers use a memory hierarchy, storage hierarchy, which puts fast but expensive and small storage options close to the CPU and slower but less expensive and larger options further away. Generally, the fast volatile technologies (which lose data when off power) are referred to as "memory", while slower persistent technologies are referred to as "storage". Even the first computer designs, Charles Babbage's Analytical Engine and Percy Ludgate's Analytical Machine, clearly distinguished between processing and memory (Babbage stored numbers as rotations of gears, while Ludgate stored numbers as displacements of rods in shuttles). This distinction was extended in t ... [...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 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 code assembly and disassembly capabilities. Motorola published the MIKBUG ROM monitor for the 6800 in 1973 and the BUFFALO ROM monitor for the 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, Heathkit H89 and Zenith laptops). Often, computer manufacturers rely on their ROM-resident monitors to permit users to reconfigure their computers following installation of upgrade hardware, such as expanded main ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interpreter (computing)
In computer science, an interpreter is a computer program that directly execution (computers), executes instructions written in a Programming language, programming or scripting language, without requiring them previously to have been Compiler, 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; # Translator (computing), 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 Virtual Machine. Early versions of Lisp programming language and BASIC interpreter, minicomputer and microcomputer BASIC dialects would be examples of the first type. Perl, Raku (programming language), Raku, Python (programming language), Python, MATLAB, and Ruby (programming language), Ruby are examples of the second, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BASIC
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College in 1963. They wanted to enable students in non-scientific fields to use computers. At the time, nearly all computers required writing custom software, which only scientists and mathematicians tended to learn. In addition to the program language, Kemeny and Kurtz developed the Dartmouth Time Sharing System (DTSS), which allowed multiple users to edit and run BASIC programs simultaneously on remote terminals. This general model became very popular on minicomputer systems like the PDP-11 and Data General Nova in the late 1960s and early 1970s. Hewlett-Packard produced an entire computer line for this method of operation, introducing the HP2000 series in the late 1960s and continuing sales into the 1980s. Many early video games trace their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
