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Compukit UK101
The Compukit UK101 microcomputer (1979) is a kit clone of the Ohio Scientific Superboard II single-board computer, with a few enhancements for the UK market - notably replacing the 24×24 (add guardband kit to give 32×32) screen display with a more useful 48×16 layout working at UK video frequencies. The video output is black and white with 256 characters generated by a two kilobyte ROM. It has no bit-mapped graphics capability. The video is output through a UHF modulator, designed to connect to a TV set. History The UK101 design was published in Practical Electronics, a popular hobbyists magazine at the time. The August, September, October and November 1979 issues carried the four parts of the article, credited to "Dr A. A. Berk". Later issues of the magazine contained information on modifications and additions to the machine, including a series of articles on building an expansion unit. Kits of parts for building the machine were available from CompShop Ltd of 14 Stati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcomputer
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM System z machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense). An early use of the term ''personal computer'' in 1962 predates microprocessor-based designs. ''(See "Personal Computer: Computers at Companies" reference below)''. A ''microcomputer'' used as an embedded control system may have no human-readable input ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opcode
In computing, an opcode (abbreviated from operation code, also known as instruction machine code, instruction code, instruction syllable, instruction parcel or opstring) is the portion of a machine language instruction that specifies the operation to be performed. Beside the opcode itself, most instructions also specify the data they will process, in the form of operands. In addition to opcodes used in the instruction set architectures of various CPUs, which are hardware devices, they can also be used in abstract computing machines as part of their byte code specifications. Overview Specifications and format of the opcodes are laid out in the instruction set architecture ( ISA) of the processor in question, which may be a general CPU or a more specialized processing unit. Opcodes for a given instruction set can be described through the use of an opcode table detailing all possible opcodes. Apart from the opcode itself, an instruction normally also has one or more specifiers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Microcomputers
{{disambiguation, geo ...
Early may refer to: History * The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.: ** Early Christianity ** Early modern Europe Places in the United States * Early, Iowa * Early, Texas * Early Branch, a stream in Missouri * Early County, Georgia Other uses * ''Early'' (Scritti Politti album), 2005 * ''Early'' (A Certain Ratio album), 2002 * Early (name) * Early effect, an effect in transistor physics * Early Records, a record label * the early part of the morning See also * Earley (other) Earley is a town in England. Earley may also refer to: * Earley (surname), a list of people with the surname Earley * Earley (given name), a variant of the given name Earlene * Earley Lake, a lake in Minnesota *Earley parser, an algorithm *Earley ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WDC 65C21
The W65C21S is a very flexible Peripheral Interface Adapter (PIA) for use with WDC’s 65xx and other 8-bit microprocessor families. It is produced by Western Design Center (WDC). The W65C21S provides programmed microprocessor control of up to two peripheral devices (Port A and Port B). Peripheral device control is accomplished through two 8-bit bidirectional I/O Ports, with individually designed Data Direction Registers. The Data Direction Registers provide selection of data flow direction (input or output) at each respective I/O Port. Data flow direction may be selected on a line-by-line basis with intermixed input and output lines within the same port. The “handshake” interrupt control feature is provided by four peripheral control lines. This capability provides enhanced control over data transfer functions between the microprocessor and peripheral devices, as well as bidirectional data transfer between W65C21S Peripheral Interface Adapters in multiprocessor systems. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spangles Muldoon
Spangles Muldoon (5 October 1946 – 29 February 2008), real name Chris Cary, was a radio broadcaster best known for his work on British offshore radio stations Radio Caroline and Radio North Sea International. He died in February 2008, aged 61 after suffering from a stroke A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin .... Cary was a key figure in the British rock music radio revolution of the 1960s. Cary was one of the DJs who broadcast from the offshore pirate radio ship Radio Caroline in 1967 and 1968. At its peak the station had 23 million listeners. In the 1970s Cary was a DJ on RNI before a stint at Radio Luxembourg.Chris worked on Radio Caroline when they came back on air in 1972 after being in port of Amsterdam for 5 years (since 1968) and later went to Radio Luxenbourg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RS-232
In telecommunications, RS-232 or Recommended Standard 232 is a standard originally introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' (''data terminal equipment'') such as a computer terminal, and a ''DCE'' (''data circuit-terminating equipment'' or ''data communication equipment''), such as a modem. The standard defines the electrical characteristics and timing of signals, the meaning of signals, and the physical size and pinout of connectors. The current version of the standard is ''TIA-232-F Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange'', issued in 1997. The RS-232 standard had been commonly used in computer serial ports and is still widely used in industrial communication devices. A serial port complying with the RS-232 standard was once a standard feature of many types of computers. Personal computers used them for connection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asynchronous Communications Interface Adapter
The 6551 Asynchronous Communications Interface Adapter (ACIA) was an integrated circuit made by MOS Technology. It served as a companion UART chip for the widely popular 6502 microprocessor. Intended to implement RS-232, its specifications called for a maximum speed of 19,200 bits per second with its onboard baud-rate generator, or 125kbit/s using an external 16x clock. The 6551 was used in several computers of the 1970s and 1980s, including the Commodore PET and Commodore Plus/4. It was also used by Apple Computer on the Super Serial Card for their Apple II series, and by RadioShack, Radio Shack on the Deluxe RS-232 Program Pak for their Color Computer. Commodore International omitted the 6551 from the popular VIC-20, C64, and C128 home computers. Instead, these systems implemented a bit-banging UART via KERNAL routines. This RS-232 implementation was not reliable over 1200 bit/s (see errata comments in the 6526 article), forcing some programmers of terminal programs to writ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kansas City Standard
The Kansas City standard (KCS), or ''Byte'' standard, is a data storage protocol for standard cassette tapes at . It originated in a symposium sponsored by Byte (magazine), ''Byte'' magazine in November 1975 in Kansas City, Missouri to develop a standard for the storage of digital microcomputer data on inexpensive consumer quality cassettes. The first systems based on the standard appeared in 1976. One variation on the basic standard is CUTS, which is identical at 300 bit/s, but with an optional 1200 bit/s mode. CUTS is the default encoding used by several later machine families, including those from Acorn Computers, Acorn and the MSX. MSX added a higher 2400 bit/s mode that is otherwise similar. The 1200 bit/s mode of CUTS was used as the standard for cross-platform BASICODE distribution. KCS originated from the earliest days of the microcomputer revolution, among other prolific protocols. Most home computers of the era have List of cassette tape data storag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typeahead
Typeahead is a feature of computers and software (and some typewriters) that enables users to continue typing regardless of program or computer operation—the user may type in whatever speed is desired, and if the receiving software is busy at the time it will be called to handle this later. Often this means that keystrokes entered will not be displayed on the screen immediately. This programming technique for handling uses what is known as a keyboard buffer. Typeahead has its roots in the age of typewriters. The IBM Selectric typewriter, first released in 1961, had a mechanical key lockout feature designed to smooth out typists' irregular keystrokes that, to many users, felt like typeahead. Achieving true typeahead requires maintaining a so-called "typeahead buffer"—a FIFO queue, for instance—whose role it is to store a limited amount of keyboard input until it is called for. Installing such a buffer can be done at both the hardware and the software levels; most modern oper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexadecimal
In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of 16. Unlike the decimal system representing numbers using 10 symbols, hexadecimal uses 16 distinct symbols, most often the symbols "0"–"9" to represent values 0 to 9, and "A"–"F" (or alternatively "a"–"f") to represent values from 10 to 15. Software developers and system designers widely use hexadecimal numbers because they provide a human-friendly representation of binary-coded values. Each hexadecimal digit represents four bits (binary digits), also known as a nibble (or nybble). For example, an 8-bit byte can have values ranging from 00000000 to 11111111 in binary form, which can be conveniently represented as 00 to FF in hexadecimal. In mathematics, a subscript is typically used to specify the base. For example, the decimal value would be expressed in hexadecimal as . In programming, a number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrolling
In computer displays, filmmaking, television production, and other kinetic displays, scrolling is sliding text, images or video across a monitor or display, vertically or horizontally. "Scrolling," as such, does not change the layout of the text or pictures but moves ( pans or tilts) the user's view across what is apparently a larger image that is not wholly seen. A common television and movie special effect is to scroll credits, while leaving the background stationary. Scrolling may take place completely without user intervention (as in film credits) or, on an interactive device, be triggered by touchscreen or a keypress and continue without further intervention until a further user action, or be entirely controlled by input devices. Scrolling may take place in discrete increments (perhaps one or a few lines of text at a time), or continuously (smooth scrolling). Frame rate is the speed at which an entire image is redisplayed. It is related to scrolling in that changes to text a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semigraphics
Text-based semigraphics or pseudographics is a primitive method used in early text mode video hardware to emulate raster graphics without having to implement the logic for such a display mode. There are two different ways to accomplish the emulation of raster graphics. The first one is to create a low-resolution all points addressable mode using a set of special characters with all binary combinations of a certain subdivision matrix of the text mode character size; this method is referred to as block graphics, or sometimes mosaic graphics. The second one is to use special shapes instead of glyphs (letters and figures) that appear as if drawn in raster graphics mode, sometimes referred to as semi- or pseudo-graphics; an important example of this is box-drawing characters. Semigraphical characters (including some block elements) are still incorporated into the BIOS of any VGA compatible video card, so any PC can display these characters from the moment it is turned on, even whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
