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IBM 2821 Control Unit
The IBM 2821 Control Unit attaches card readers and card punches, and line printers to the IBM System/360 and IBM System/370 families of computers. The devices attached may be a combination of: * The IBM 2540 card reader and card punch; * The IBM 1403 models 2, 3, 7 and N1 line printer; and * The IBM 1404 model 2 line printer and bill feed printer. The 2821 was originally advertised—in 1964, before System/360 shipped—as a controller for the IBM 1402 card reader/punch and the IBM 1403 and IBM 2201 printers. Six models of the IBM 2821 Control Unit were available, as follows: * Model 1 attaches one IBM 2540 and one IBM 1403; * Model 2 attaches one IBM 1403; * Model 3 attaches two or three IBM 1403s; * Model 4 attaches one IBM 2540 and one IBM 1404, but only on IBM System/360 models 25, 30, 40 and 50; * Model 5 attaches one IBM 2540 and two or three IBM 1403s; and * Model 6 attaches one IBM 2540 The IBM 2540 is a punched-card computer peripheral manufactured by IBM Corp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1970 CNRZ Mécanographie-3-cliche Jean Weber
Year 197 ( CXCVII) was a common year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Magius and Rufinus (or, less frequently, year 950 ''Ab urbe condita''). The denomination 197 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * February 19 – Battle of Lugdunum: Emperor Septimius Severus defeats the self-proclaimed emperor Clodius Albinus at Lugdunum (modern Lyon). Albinus commits suicide; legionaries sack the town. * Septimius Severus returns to Rome and has about 30 of Albinus's supporters in the Senate executed. After his victory he declares himself the adopted son of the late Marcus Aurelius. * Septimius Severus forms new naval units, manning all the triremes in Italy with heavily armed troops for war in the East. His soldiers embark on a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punched Card Input/output
A computer punched card reader or just computer card reader is a computer input device used to read computer programs in either source or executable form and data from punched cards. A computer card punch is a computer output device that punches holes in cards. Sometimes computer punch card readers were combined with computer card punches and, later, other devices to form multifunction machines. It is a input device and also an output device. Most early computers, such as the ENIAC, and the IBM NORC, provided for punched card input/output. Card readers and punches, either connected to computers or in off-line card to/from magnetic tape configurations, were ubiquitous through the mid-1970s. Punched cards had been in use since the 1890s; their technology was mature and reliable. Card readers and punches developed for punched card machines were readily adaptable for computer use. Businesses were familiar with storing data on punched cards and keypunch machines were widely emplo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Line Printer
A line printer prints one entire line of text before advancing to another line. Most early line printers were impact printers. Line printers are mostly associated with unit record equipment and the early days of digital computing, but the technology is still in use. Print speeds of 600 lines per minute (approximately 10 pages per minute) were achieved in the 1950s, later increasing to as much as 1200 lpm. Line printers print a complete line at a time and have speeds in the range of 150 to 2500 lines per minute. The types of line printers are drum printers, band-printers, and chain printers. Other non-impact technologies have also been used, as thermal line printers were popular in the 1970s and 1980s, and some inkjet and laser printers produce output a line or a page at a time. Designs Many impact printers, such as the daisywheel printer and dot matrix printer, used a print head that printed a character then moved on until an entire line was printed. Line printers wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/360
The IBM System/360 (S/360) is a family of mainframe computer systems that was announced by IBM on April 7, 1964, and delivered between 1965 and 1978. It was the first family of computers designed to cover both commercial and scientific applications and to cover a complete range of applications from small to large. The design distinguished between architecture and implementation, allowing IBM to release a suite of compatible designs at different prices. All but the only partially compatible Model 44 and the most expensive systems use microcode to implement the instruction set, which features 8-bit byte addressing and binary, decimal, and hexadecimal floating-point calculations. The System/360 family introduced IBM's Solid Logic Technology (SLT), which packed more transistors onto a circuit card, allowing more powerful but smaller computers to be built. The slowest System/360 model announced in 1964, the Model 30, could perform up to 34,500 instructions per second, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/370
The IBM System/370 (S/370) is a model range of IBM mainframe computers announced on June 30, 1970, as the successors to the System/360 family. The series mostly maintains backward compatibility with the S/360, allowing an easy migration path for customers; this, plus improved performance, were the dominant themes of the product announcement. In September 1990, the System/370 line was replaced with the System/390. Evolution The original System/370 line was announced on June 30, 1970, with first customer shipment of the Models 155 and 165 planned for February 1971 and April 1971 respectively. The 155 first shipped in January 1971. System/370 underwent several architectural improvements during its roughly 20-year lifetime. The following features mentioned in Principles of Operation are either optional on S/360 but standard on S/370, introduced with S/370 or added to S/370 after announcement. *Branch and Save *Channel Indirect Data Addressing *Channel-Set Switching *Clear I/O *C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 2540
The IBM 2540 is a punched-card computer peripheral manufactured by IBM Corporation for use of System/360 and later computer systems. The 2540 was designed by IBM's Data Processing Division in Rochester, Minnesota, and was introduced in 1965. The 2540 can read punched-cards at 1000 cards per minute (CPM) and punch at 300 CPM. The 2540 is based on the design of the older, slightly slower, 1402. Description The 2540 attaches to a System/360 multiplexer or selector channel through an IBM 2821 Control Unit. A standard 2540 processes standard IBM 80 column punched cards. The card reader (2540R) and card punch (2540P) devices are separately addressable and function independently. The 2540 normally reads and punches EBCDIC data, called data-mode 1. Card reader On the right side of the device is the reader, consisting of an input hopper holding approximately 3100 cards, and three output stackers (right to left – R1, R2, and RP3) each holding approximately 1350 cards. Cards c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 1403
The IBM 1403 line printer was introduced as part of the IBM 1401 computer in 1959 and had an especially long life in the IBM product line. Description The original model can print 600 lines of text per minute and can skip blank lines at up to 75 inches per second (190 cm/s), while the model 3 can print at up to 1400 lines per minute. The standard model has 120 print positions. An additional 12 positions are available as an option. A print chain with up to 15 copies of the character set spins horizontally in front of the ribbon and paper. Hammers strike the paper from behind at exactly the right moment to print a character as it goes by. In later models, the print chain is replaced by a print train; print slugs instead of being mounted on a chain are placed in a track. The 1403 chain or train contains 240 characters, however numerous duplications allow a line to be printed in less than the 0.4 s required for one full rotation. The original standard "A" chain co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 1404
The IBM 1403 line printer was introduced as part of the IBM 1401 computer in 1959 and had an especially long life in the IBM product line. Description The original model can print 600 lines of text per minute and can skip blank lines at up to 75 inches per second (190 cm/s), while the model 3 can print at up to 1400 lines per minute. The standard model has 120 print positions. An additional 12 positions are available as an option. A print chain with up to 15 copies of the character set spins horizontally in front of the ribbon and paper. Hammers strike the paper from behind at exactly the right moment to print a character as it goes by. In later models, the print chain is replaced by a print train; print slugs instead of being mounted on a chain are placed in a track. The 1403 chain or train contains 240 characters, however numerous duplications allow a line to be printed in less than the 0.4 s required for one full rotation. The original standard "A" chain co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 1402
The IBM 1402 was a high speed card reader/punch introduced on October 5, 1959 as a peripheral input/output device for the IBM 1401 computer. It was later used with other computers of the IBM 1400 series and IBM 7000 series product lines. It was adapted as the IBM 1622 Card Read-Punch for the IBM 1620 and provided the basic design for the models 2501, 2520 and 2540 equipment used with the IBM System/360 product line. Specifications Card reader * Card read speed up to 800 punched cards per minute (models 1, 2 and 3) or 450 cards per minute (models 4, 5 and 6). * Card input file for 3,000 cards (models 1, 2, 3, 4 and 6) or feed hopper for 1,200 cards (model 5). * Three stackers (NR, 1, 2/8) with approximately 1,000-card capacity hold cards after they are read. Card punch * Card punch speed up to 250 cards per minute (all models). * Feed hopper for 1,200 cards (all models). * Three stackers (NP, 4, 2/8) of approximately 1,000-card capacity after cards are punched. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Buffer
In computer science, a data buffer (or just buffer) is a region of a memory used to temporarily store data while it is being moved from one place to another. Typically, the data is stored in a buffer as it is retrieved from an input device (such as a microphone) or just before it is sent to an output device (such as speakers). However, a buffer may be used when moving data between processes within a computer. This is comparable to buffers in telecommunication. Buffers can be implemented in a fixed memory location in hardware—or by using a virtual data buffer in software, pointing at a location in the physical memory. In all cases, the data stored in a data buffer are stored on a physical storage medium. A majority of buffers are implemented in software, which typically use the faster RAM to store temporary data, due to the much faster access time compared with hard disk drives. Buffers are typically used when there is a difference between the rate at which data is received and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channel I/O
In computing, channel I/O is a high-performance input/output (I/O) architecture that is implemented in various forms on a number of computer architectures, especially on mainframe computers. In the past, channels were generally implemented with custom devices, variously named channel, I/O processor, I/O controller, I/O synchronizer, or '' DMA controller''. Overview Many I/O tasks can be complex and require logic to be applied to the data to convert formats and other similar duties. In these situations, the simplest solution is to ask the CPU to handle the logic, but because I/O devices are relatively slow, a CPU could waste time (in computer perspective) waiting for the data from the device. This situation is called 'I/O bound'. Channel architecture avoids this problem by processing some or all of the I/O task without the aid of the CPU by offloading the work to dedicated logic. Channels are logically self-contained, with sufficient logic and working storage to handle I/O tasks. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
