|
IBM 702
The IBM 702 was an early generation tube-based digital computer produced by IBM in the early to mid-1950s. It was the company's response to Remington Rand's UNIVAC, which was the first mainframe computer to use magnetic tapes. As these machines were aimed at the business market, they lacked the leading-edge computational power of the IBM 701 and ERA 1103, which were favored for scientific computing, weather forecasting, the aircraft industry, and the military and intelligence communities. Within IBM, the 702 was notable for adapting the new technology of magnetic-core memory for random-access applications. The 702 was announced September 25, 1953, and withdrawn October 1, 1954, but the first production model was not installed until July 1955. It was superseded by the IBM 705. History Fourteen 702s were built. The first one was used at IBM. Due to problems with the Williams tubes, the decision was made to switch to magnetic-core memory instead. The fourteenth 702 was built usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Character (computing)
In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme, grapheme-like unit, or symbol, such as in an alphabet or syllabary in the written form of a natural language. Examples of characters include letters, numerical digits, common punctuation marks (such as "." or "-"), and whitespace. The concept also includes control characters, which do not correspond to visible symbols but rather to instructions to format or process the text. Examples of control characters include carriage return and tab as well as other instructions to printers or other devices that display or otherwise process text. Characters are typically combined into strings. Historically, the term ''character'' was used to denote a specific number of contiguous bits. While a character is most commonly assumed to refer to 8 bits (one byte) today, other options like the 6-bit character code were once popular, and the 5-bit Baudot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Vacuum Tube Computers
Vacuum-tube computers, now called first-generation computers, are programmable digital computers using vacuum-tube logic circuitry. They were preceded by systems using electromechanical relays and followed by systems built from discrete transistors. Some later computers on the list had both vacuum tubes and transistors. This list of vacuum-tube computers is sorted by date put into service: }) are identical, except input-output equipment. Both were used internally. , - , The Wegematic 1000 , , 1960 , , , Improved version of the ALWAC III-E , - , ZRA 1 , , 1960 , , , Built by VEB Carl Zeiss, Jena, German Democratic RepublicSiegmar Gerber: ''Einsatz von Zeiss-Rechnern für Forschung, Lehre und Dienstleistung in Informatik in der DDR – eine Bilanz''. GI-Edition, Bonn 2006, p. 310–318 , - , Minsk-1 , , 1960 , , , Built in Minsk , - , Odra 1001 , , 1960 , , , First computer built by Elwro, Wroclaw, Poland , - , Minsk-1 , , 1960 , , , Built in Minsk , - ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drum Memory
Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. Drums were widely used in the 1950s and into the 1960s as computer memory. For many early computers, drum memory formed the main working memory of the computer. It was so common that these computers were often referred to as ''drum machines''. Some drums were also used as secondary storage as for example various IBM drum storage drives. Drums were displaced as primary computer memory by magnetic core memory, which offered a better balance of size, speed, cost, reliability and potential for further improvements. Drums in turn were replaced by hard disk drives for secondary storage, which were both less expensive and offered denser storage. The manufacturing of drums ceased in the 1970s. Technical design A drum memory or drum storage unit contained a large metal cylinder, coated on the outside surface with a ferromagnetic recording material. It could be considered the precu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 727
The IBM 727 Magnetic Tape Unit was announced for the IBM 701 and IBM 702 on September 25, 1953. It became IBM's standard tape drive for their early vacuum-tube era computer systems. Later vacuum-tube machines and first-generation transistor computers used the IBM 729-series tape drive. The 727 was withdrawn on May 12, 1971. The tape had seven parallel tracks – six for data and one to maintain parity. Tapes with character data ( BCD) were recorded in even parity. Binary tapes used odd parity. Aluminum strips were glued several feet from the ends of the tape to serve as logical beginning and end of tape markers. Write protection Write protection is any physical mechanism that prevents writing, modifying, or erasing data on a device. Most commercial software, audio and video on writeable media is write-protected when distributed. Examples * IBM -inch magnetic tape r ... was provided by a removable plastic ring in the back of the tape reel. References 727 Tape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Printer (computing)
In computing, a printer is a peripheral machine which makes a persistent representation of graphics or text, usually on paper. While most output is human-readable, bar code printers are an example of an expanded use for printers. Different types of printers include 3D printers, inkjet printers, laser printers, and thermal printers. History The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his difference engine in the 19th century; however, his mechanical printer design was not built until 2000. The first patented printing mechanism for applying a marking medium to a recording medium or more particularly an electrostatic inking apparatus and a method for electrostatically depositing ink on controlled areas of a receiving medium, was in 1962 by C. R. Winston, Teletype Corporation, using continuous inkjet printing. The ink was a red stamp-pad ink manufactured by Phillips Process Company of Rochester, NY under the name Clear Prin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 717
The IBM 716 line printer was used with IBM 700/7000 series computers in the 1950s and 1960s. It was introduced on May 21, 1952 with the IBM 701 and withdrawn from marketing on July 14, 1969. Overview The 716 was based on IBM 407 accounting machine technology and had 120 rotary type wheels, each with 48 possible characters. It could print 150 lines per minute. It also supplied power to the IBM 711 card reader and 721 card punch. Only 72 characters could be transferred from IBM 7090 computer to the 716 in a single operation, but a full line could be printed at half speed. Characters were printed by sending bit patterns that corresponded to the impulses that a 407 would see when reading a punched card. 1961, IBM A22-6528-3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 712
The IBM 711 was a punched card reader used as a peripheral device for IBM mainframe vacuum tube computers and early transistorized computers. Announced on May 21, 1952, it was first shipped with the IBM 701. Later IBM computers that used it were the IBM 704, the IBM 709, and the transistorized IBM 7090 and 7094. Overview The 711's read mechanism was based on the IBM 402's and could read 150 cards per minute (250 cards per minute on the IBM 7090). It included a control panel that could be wired to transfer any 72 columns out of the 80 on a card into the computer's memory, though in practice the panel was almost always wired to read the first 72 columns. Cards were read in binary format. Data from each row was read into two 36-bit words, starting with row 9, for a total of 24 words per card. Computer object code could then be executed directly. Conversion to characters or numbers was done in software. The 72 column restriction influenced early computer languages, such as Fortran a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Processing Unit
A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and input/output (I/O) operations specified by the instructions in the program. This contrasts with external components such as main memory and I/O circuitry, and specialized processors such as graphics processing units (GPUs). The form, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic–logic unit (ALU) that performs arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the fetching (from memory), decoding and execution (of instructions) by directing the coordinated operations of the ALU, registers and other co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 705
The IBM 700/7000 series is a series of large-scale (mainframe) computer systems that were made by IBM through the 1950s and early 1960s. The series includes several different, incompatible processor architectures. The 700s use vacuum-tube logic and were made obsolete by the introduction of the transistorized 7000s. The 7000s, in turn, were eventually replaced with System/360, which was announced in 1964. However the 360/65, the first 360 powerful enough to replace 7000s, did not become available until November 1965. Early problems with OS/360 and the high cost of converting software kept many 7000s in service for years afterward. Architectures The IBM 700/7000 series has six completely different ways of storing data and instructions: *First scientific (36/18- bit words): 701 (Defense Calculator) *Later scientific (36-bit words, hardware floating-point): 704, 709, 7040, 7044, 7090, 7094 *Commercial (variable-length character strings): 702, 705, 7080 * 1400 series ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplification and current rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—from the cathode to the anode. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> List Of Vacuum Tube Computers")
