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78-592: The SGI IRIS series of terminals and workstations from Silicon Graphics was produced in the 1980s and 1990s. IRIS is an acronym for Integrated Raster Imaging System. Silicon Graphics Computer Systems' first product, shipped in November 1983, was the IRIS 1000, a terminal with hardware-accelerated 3D graphics based on the Geometry Engine developed by Jim Clark and Marc Hannah at Stanford University . As

156-499: A Motorola 68000 (or 68010) clocked at 8 MHz. With the IRIS 2000 series (released in 1985) came SGCS's first internally-designed processor, with a Motorola 68010 running at 10 MHz. The final Motorola 68000-based series, the 3000s released in 1986, were built around a 68020 running at 16 MHz. These systems ran the GL1, then GL2 operating system, a predecessor of the IRIX operating system, which

234-502: A 4D/210 would have one processor, a 4D/340 would have 4 processors, etc. The Power IRIS series was ultimately eclipsed, first by the 64-bit MIPS R4000 -based IRIS Crimson , and then by the POWERpath-2 based Onyx and Challenge series. The Personal IRIS line consisted of four main models - the 4D/20, /25, /30, and /35. The /20 and /25 were both released in 1988, with the /30 and /35 debuting in 1990. With an entry price of £10,300,

312-478: A built-in keyboard and display for the console. Some Unix-like operating systems such as Linux and FreeBSD have virtual consoles to provide several text terminals on a single computer. The fundamental type of application running on a text terminal is a command-line interpreter or shell , which prompts for commands from the user and executes each command after a press of Return . This includes Unix shells and some interactive programming environments. In

390-452: A computer screen by decades. The computer would typically transmit a line of data which would be printed on paper, and accept a line of data from a keyboard over a serial or other interface. Starting in the mid-1970s with microcomputers such as the Sphere 1 , Sol-20 , and Apple I , display circuitry and keyboards began to be integrated into personal and workstation computer systems, with

468-430: A field that may have previously required a full screen-full of characters to be re-sent from the computer, possibly over a slow modem line. Around the mid-1980s most intelligent terminals, costing less than most dumb terminals would have a few years earlier, could provide enough user-friendly local editing of data and send the completed form to the main computer. Providing even more processing possibilities, workstations like

546-684: A generic MIPS systems board (likewise, the earliest versions of the new operating system for the MIPS-based workstations, dubbed '4D1' , was largely derived from MIPS' own RISC/OS ). In 1988, SGCS superseded the Professional IRIS line with the higher-end Power IRIS line (specializing in Symmetric Multi-Processing , and so-named for its proprietary POWERpath architecture), and the lower-end Personal IRIS line. The Power IRIS systems (later dubbed "PowerSeries") came in

624-530: A green or amber screen. Typically terminals communicate with the computer via a serial port via a null modem cable, often using an EIA RS-232 or RS-422 or RS-423 or a current loop serial interface. IBM systems typically communicated over a Bus and Tag channel, a coaxial cable using a proprietary protocol, a communications link using Binary Synchronous Communications or IBM's SNA protocol, but for many DEC, Data General and NCR (and so on) computers there were many visual display suppliers competing against

702-622: A keyboard in 1941, as did the Z4 in 1942–1945. However, these consoles could only be used to enter numeric inputs and were thus analogous to those of calculating machines; programs, commands, and other data were entered via paper tape. Both machines had a row of display lamps for results. In 1956, the Whirlwind Mark ;I computer became the first computer equipped with a keyboard-printer combination with which to support direct input of data and commands and output of results. That device

780-461: A library such as ncurses . For more complex operations, the programs can use terminal specific ioctl system calls. For an application, the simplest way to use a terminal is to simply write and read text strings to and from it sequentially. The output text is scrolled, so that only the last several lines (typically 24) are visible. Unix systems typically buffer the input text until the Enter key

858-613: A microprocessor is built in, but not all terminals with microprocessors did any real processing of input: the main computer to which it was attached would have to respond quickly to each keystroke. The term "intelligent" in this context dates from 1969. Notable examples include the IBM 2250 , predecessor to the IBM 3250 and IBM 5080, and IBM 2260 , predecessor to the IBM 3270 , introduced with System/360 in 1964. Most terminals were connected to minicomputers or mainframe computers and often had

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936-408: A number of configurations, with anywhere between 1 and 8 processors and coming in either a twin-tower chassis akin to the Professional IRIS, a mini-fridge sized desk-side chassis (code-named 'Diehard'), or a full rack-sized chassis (code-named 'Predator'). One could determine the processor count of a Power IRIS system from its model number - the second digit would directly indicate the number of CPUs, so

1014-594: A real-world terminal, sometimes allowing concurrent use of local programs and access to a distant terminal host system, either over a direct serial connection or over a network using, e.g., SSH . Today few if any dedicated computer terminals are being manufactured, as time sharing on large computers has been replaced by personal computers, handheld devices and workstations with graphical user interfaces. User interactions with servers use either software such as Web browsers , or terminal emulators, with connections over high-speed networks. The console of Konrad Zuse 's Z3 had

1092-593: A sequence of codes were sent to the terminal to try to read the cursor's position or the 25th line's contents using a sequence of different manufacturer's control code sequences, and the terminal-generated response would determine a single-digit number (such as 6 for Data General Dasher terminals, 4 for ADM 3A/5/11/12 terminals, 0 or 2 for TTYs with no special features) that would be available to programs to say which set of codes to use. The great majority of terminals were monochrome, manufacturers variously offering green, white or amber and sometimes blue screen phosphors. (Amber

1170-472: A shell, most of the commands are small applications themselves. Another important application type is that of the text editor . A text editor typically occupies the full area of display, displays one or more text documents, and allows the user to edit the documents. The text editor has, for many uses, been replaced by the word processor , which usually provides rich formatting features that the text editor lacks. The first word processors used text to communicate

1248-455: A standard, AlphaWindows , that would allow a single CRT screen to implement multiple windows, each of which was to behave as a distinct terminal. Unfortunately, like I2O , this suffered from being run as a closed standard: non-members were unable to obtain even minimal information and there was no realistic way a small company or independent developer could join the consortium. An intelligent terminal does its own processing, usually implying

1326-446: A terminal as "intelligent" was its ability to process user-input within the terminal—not interrupting the main computer at each keystroke—and send a block of data at a time (for example: when the user has finished a whole field or form). Most terminals in the early 1980s, such as ADM-3A, TVI912, Data General D2, DEC VT52 , despite the introduction of ANSI terminals in 1978, were essentially "dumb" terminals, although some of them (such as

1404-452: A terminal, it was not intended for standalone use, and was instead attached to a VAX-11 running VAX/VMS or Unix . It was soon followed by the IRIS 1200, another terminal with a larger backplane , before the IRIS 1400 emerged as SGCS's first standalone workstation in 1984. The processor used in these early systems, the 'PM1', was a variant of the SUN (Stanford UNiversity) processor, and sported

1482-456: A typical application the host sends the terminal a preformatted panel containing both static data and fields into which data may be entered. The terminal operator keys data, such as updates in a database entry, into the appropriate fields. When entry is complete (or ENTER or PF key pressed on 3270s), a block of data, usually just the data entered by the operator (modified data), is sent to the host in one transmission. The 3270 terminal buffer (at

1560-402: Is " thin client ". A thin client typically uses a protocol like X11 for Unix terminals, or RDP for Microsoft Windows. The bandwidth needed depends on the protocol used, the resolution, and the color depth . Modern graphic terminals allow display of images in color, and of text in varying sizes, colors, and fonts (type faces). In the early 1990s, an industry consortium attempted to define

1638-626: Is a discontinued operating system developed by Silicon Graphics (SGI) to run on the company's proprietary MIPS workstations and servers. It is based on UNIX System V with BSD extensions. In IRIX, SGI originated the XFS file system and the industry-standard OpenGL graphics API . SGI originated the IRIX name in the 1988 release 3.0 of the operating system for the SGI IRIS 4D series of workstations and servers. Previous releases are identified only by

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1716-405: Is a proprietary serial-based keyboard/mouse protocol. Earlier machines use either a DE-15 (68K, Professional, PowerSeries) or DE-9 (4D/20, /25) connector, with the later machines (4D/30, /35, Indigo, Crimson, Onyx) using a mini DIN-6 which is easy to confuse with a standard PS/2 connector. One must take care not to insert an IRIS keyboard into a PS/2 port or vice versa, as the voltage levels used in

1794-406: Is a serial computer interface for text entry and display. Information is presented as an array of pre-selected formed characters . When such devices use a video display such as a cathode-ray tube , they are called a " video display unit " or "visual display unit" (VDU) or "video display terminal" (VDT). The system console is often a text terminal used to operate a computer. Modern computers have

1872-522: Is a type of computer terminal that communicates with its host in blocks of data, as opposed to a character-oriented terminal that communicates with its host one character at a time. A block-oriented terminal may be card-oriented, display-oriented, keyboard-display, keyboard-printer, printer or some combination. The IBM 3270 is perhaps the most familiar implementation of a block-oriented display terminal, but most mainframe computer manufacturers and several other companies produced them. The description below

1950-495: Is achieved via RS-232 serial links, Ethernet or other proprietary protocols . Character-oriented terminals can be "dumb" or "smart". Dumb terminals are those that can interpret a limited number of control codes (CR, LF, etc.) but do not have the ability to process special escape sequences that perform functions such as clearing a line, clearing the screen, or controlling cursor position. In this context dumb terminals are sometimes dubbed glass Teletypes , for they essentially have

2028-402: Is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. Most early computers only had a front panel to input or display bits and had to be connected to a terminal to print or input text through a keyboard. Teleprinters were used as early-day hard-copy terminals and predated the use of

2106-463: Is based on UniSoft UniPlus System V Unix . GL2 uses a proprietary (and highly rudimentary) windowing system named mex (Multiple EXposure). Beginning in 1987, SGCS began selling workstations with MIPS RISC processors rather than the Motorola 680x0. These new systems adopted a different numbering scheme, with the prefix '4D/' followed by a two-to-three digit number. The first of these systems

2184-462: Is called a " dumb terminal " or a thin client . In the era of serial ( RS-232 ) terminals there was a conflicting usage of the term "smart terminal" as a dumb terminal with no user-accessible local computing power but a particularly rich set of control codes for manipulating the display; this conflict was not resolved before hardware serial terminals became obsolete. A personal computer can run terminal emulator software that replicates functions of

2262-515: Is compliant with UNIX System V Release 4, UNIX 95 , and POSIX (including 1e/2c draft 15 ACLs and Capabilities). In the early 1990s, IRIX was a leader in Symmetric Multi-Processing (SMP) , scalable from 1 to more than 1,024 processors with a single system image. IRIX has strong support for real-time disk and graphics I/O. IRIX was widely used for the 1990s and 2000s in the computer animation and scientific visualization industries, due to its large application base and high performance. It still

2340-462: Is in terms of the 3270, but similar considerations apply to other types. Block-oriented terminals typically incorporate a buffer which stores one screen or more of data, and also stores data attributes, not only indicating appearance (color, brightness, blinking, etc.) but also marking the data as being enterable by the terminal operator vs. protected against entry, as allowing the entry of only numeric information vs. allowing any characters, etc. In

2418-400: Is limited, the number of concurrent lines that can be displayed at one time is limited. Vector-mode displays were historically important but are no longer used. Practically all modern graphic displays are raster-mode, descended from the picture scanning techniques used for television , in which the visual elements are a rectangular array of pixels . Since the raster image is only perceptible to

SGI IRIS - Misplaced Pages Continue

2496-444: Is pressed, so the application receives a ready string of text. In this mode, the application need not know much about the terminal. For many interactive applications this is not sufficient. One of the common enhancements is command-line editing (assisted with such libraries as readline ); it also may give access to command history. This is very helpful for various interactive command-line interpreters. Even more advanced interactivity

2574-428: Is provided with full-screen applications. Those applications completely control the screen layout; also they respond to key-pressing immediately. This mode is very useful for text editors, file managers and web browsers . In addition, such programs control the color and brightness of text on the screen, and decorate it with underline, blinking and special characters (e.g. box-drawing characters ). To achieve all this,

2652-457: Is relevant in a few legacy applications. IRIX is one of the first Unix versions to feature a graphical user interface for the main desktop environment. IRIX Interactive Desktop uses the 4Dwm X window manager with a custom look designed using the Motif widget toolkit . IRIX is the originator of the industry standard OpenGL for graphics chips and image processing libraries. IRIX uses

2730-603: Is the window manager component of the IRIX Interactive Desktop normally used on Silicon Graphics workstations running IRIX. 4Dwm is derived from the older Motif Window Manager and uses the Motif widget toolkit on top of the X Window System found on most Unix systems. 4Dwm on IRIX was one of the first default graphical user interface desktops to be standard on a Unix computer system. 4Dwm refers to " Fourth dimension window manager" and has no relation to dwm . Other X window managers that mimic

2808-509: The IBM 2741 (1965) and the DECwriter (1970). Respective top speeds of teletypes, IBM 2741 and the LA30 (an early DECwriter) were 10, 15 and 30 characters per second. Although at that time "paper was king" the speed of interaction was relatively limited. The DECwriter was the last major printing-terminal product. It faded away after 1980 under pressure from video display units (VDUs), with

2886-750: The Intel 8080 . This made them inexpensive and they quickly became extremely popular input-output devices on many types of computer system, often replacing earlier and more expensive printing terminals. After 1970 several suppliers gravitated to a set of common standards: The experimental era of serial VDUs culminated with the VT100 in 1978. By the early 1980s, there were dozens of manufacturers of terminals, including Lear-Siegler , ADDS , Data General, DEC , Hazeltine Corporation , Heath/Zenith , Hewlett-Packard , IBM, TeleVideo , Volker-Craig, and Wyse , many of which had incompatible command sequences (although many used

2964-662: The MIPSPro compiler for both its front end and back end. The compiler, also known in earlier versions as IDO (IRIS Development Option), was released in many versions, many of which are coupled to the OS version. The last version was 7.4.4m, designed for 6.5.19 or later. The compiler is designed to support parallel POSIX programming in C/C++, Fortran 77/90, and Ada. The Workshop GUI IDE is used for development. Other tools include Speedshop for performance tuning, and Performance Co-Pilot . 4Dwm

3042-506: The VT220 terminal strongly influenced the Model M shipped on IBM PCs from 1985, and through it all later computer keyboards. Although flat-panel displays were available since the 1950s, cathode-ray tubes continued to dominate the market until the personal computer had made serious inroads into the display terminal market. By the time cathode-ray tubes on PCs were replaced by flatscreens after

3120-799: The Windows -based SGI Visual Workstation but MIPS and IRIX customers convinced SGI to continue to support its platform through 2006. On September 6, 2006, an SGI press release announced the end of the MIPS and IRIX product lines. Production ended on December 29, 2006, with final deliveries in March 2007, except by special arrangement. Support for these products ended in December 2013 and they will receive no further updates. Much of IRIX's core technology has been open sourced and ported by SGI to Linux, including XFS. In 2009, SGI filed for bankruptcy and then

3198-532: The XFS journaling file system . In 1994, IRIX 6.0 added support for the 64-bit MIPS R8000 processor, but is otherwise similar to IRIX 5.2. Later 6.x releases support other members of the MIPS processor family in 64-bit mode. IRIX 6.3 was released for the SGI O2 workstation only. IRIX 6.4 improved multiprocessor scalability for the Octane , Origin 2000 , and Onyx2 systems. The Origin 2000 and Onyx2 IRIX 6.4

SGI IRIS - Misplaced Pages Continue

3276-558: The '4D/' model numbers. The '4D1' operating system, which from version 4D1-3 onwards was officially referred to as IRIX 4D1 (IRIX being a portmanteau of 'IRIS' and 'UNIX), would be re-branded as simply ' IRIX ' beginning in version 5, as well. However, all future MIPS-based systems released by Silicon Graphics would still use 'IRIS' as the default hostname, ending with the Tezro in 2003. A unifying feature across all IRISes – 68K, Professional, Personal, PowerSeries, Indigo, Crimson, and Onyx –

3354-482: The 4Sight windowing system , based on NeWS and IRIS GL . SGI's own Extent File System (EFS) replaces the System V filesystem. IRIX 4.0, released in 1991, replaces 4Sight with the X Window System (X11R4), the 4Dwm window manager providing a similar look and feel to 4Sight. IRIX 5.0, released in 1993, incorporates certain features of UNIX System V Release 4, including ELF executables. IRIX 5.3 introduced

3432-584: The ASR Teletype models, included a paper tape reader and punch which could record output such as a program listing. The data on the tape could be re-entered into the computer using the tape reader on the teletype, or printed to paper. Teletypes used the current loop interface that was already used in telegraphy. A less expensive Read Only (RO) configuration was available for the Teletype. Custom-designs keyboard/printer terminals that came later included

3510-591: The Personal IRIS was Silicon Graphics' cheapest workstation. The 4D/35 would later be cost-reduced into the IRIS Indigo , released in 1991, which was so architecturally similar to the 4D/35 that it shared the same Internal Processor ID (IP12) in software. Beginning in late 1992 with the release of the Indigo² and Challenge , the 'IRIS' prefix would be dropped from the names of all future systems, as well as

3588-663: The TeleVideo TS-800 could run CP/M-86 , blurring the distinction between terminal and Personal Computer. Another of the motivations for development of the microprocessor was to simplify and reduce the electronics required in a terminal. That also made it practicable to load several "personalities" into a single terminal, so a Qume QVT-102 could emulate many popular terminals of the day, and so be sold into organizations that did not wish to make any software changes. Frequently emulated terminal types included: IRIX IRIX ( / ˈ aɪ r ɪ k s / , EYE -ricks )

3666-642: The application must deal not only with plain text strings, but also with control characters and escape sequences, which allow moving the cursor to an arbitrary position, clearing portions of the screen, changing colors and displaying special characters, and also responding to function keys. The great problem here is that there are many different terminals and terminal emulators, each with its own set of escape sequences. In order to overcome this, special libraries (such as curses ) have been created, together with terminal description databases, such as Termcap and Terminfo. A block-oriented terminal or block mode terminal

3744-411: The beginning of the decade and 19.6 kbps by the end of the decade, with higher speeds possible on more expensive terminals. The function of a terminal is typically confined to transcription and input of data; a device with significant local, programmable data-processing capability may be called a "smart terminal" or fat client . A terminal that depends on the host computer for its processing power

3822-410: The computer handling character generation and outputting to a CRT display such as a computer monitor or, sometimes, a consumer TV, but most larger computers continued to require terminals. Early terminals were inexpensive devices but very slow compared to punched cards or paper tape for input; with the advent of time-sharing systems, terminals slowly pushed these older forms of interaction from

3900-569: The computer manufacturer for terminals to expand the systems. In fact, the instruction design for the Intel 8008 was originally conceived at Computer Terminal Corporation as the processor for the Datapoint 2200 . From the introduction of the IBM 3270 , and the DEC VT100 (1978), the user and programmer could notice significant advantages in VDU technology improvements, yet not all programmers used

3978-600: The development of the VDU were the Univac Uniscope and the IBM 2260 , both in 1964. These were block-mode terminals designed to display a page at a time, using proprietary protocols; in contrast to character-mode devices, they enter data from the keyboard into a display buffer rather than transmitting them immediately. In contrast to later character-mode devices, the Uniscope used synchronous serial communication over an EIA RS-232 interface to communicate between

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4056-479: The device) could be updated on a single character basis, if necessary, because of the existence of a "set buffer address order" (SBA), that usually preceded any data to be written/overwritten within the buffer. A complete buffer could also be read or replaced using the READ BUFFER command or WRITE command (unformatted or formatted in the case of the 3270). Block-oriented terminals cause less system load on

4134-423: The display, as well as the ability to switch emulation modes to mimic competitor's models, that became increasingly important selling features during the 1980s especially, when buyers could mix and match different suppliers' equipment to a greater extent than before. The advance in microprocessors and lower memory costs made it possible for the terminal to handle editing operations such as inserting characters within

4212-564: The early ADM-3 as a starting point). The great variations in the control codes between makers gave rise to software that identified and grouped terminal types so the system software would correctly display input forms using the appropriate control codes; In Unix-like systems the termcap or terminfo files, the stty utility, and the TERM environment variable would be used; in Data General's Business BASIC software, for example, at login-time

4290-624: The fact that early character-mode terminals were often deployed to replace teletype machines as a way to reduce operating costs. The next generation of VDUs went beyond teletype emulation with an addressable cursor that gave them the ability to paint two-dimensional displays on the screen. Very early VDUs with cursor addressibility included the VT05 and the Hazeltine 2000 operating in character mode, both from 1970. Despite this capability, early devices of this type were often called "Glass TTYs". Later,

4368-460: The features of the new terminals ( backward compatibility in the VT100 and later TeleVideo terminals, for example, with "dumb terminals" allowed programmers to continue to use older software). Some dumb terminals had been able to respond to a few escape sequences without needing microprocessors: they used multiple printed circuit boards with many integrated circuits ; the single factor that classed

4446-548: The host and less network traffic than character-oriented terminals. They also appear more responsive to the user, especially over slow connections, since editing within a field is done locally rather than depending on echoing from the host system. Early terminals had limited editing capabilities – 3270 terminals, for example, only could check entries as valid numerics. Subsequent "smart" or "intelligent" terminals incorporated microprocessors and supported more local processing. Programmers of block-oriented terminals often used

4524-429: The human eye as a whole for a very short time, the raster must be refreshed many times per second to give the appearance of a persistent display. The electronic demands of refreshing display memory meant that graphic terminals were developed much later than text terminals, and initially cost much more. Most terminals today are graphical; that is, they can show images on the screen. The modern term for graphical terminal

4602-419: The industry. Related developments were the improvement of terminal technology and the introduction of inexpensive video displays . Early Teletypes only printed out with a communications speed of only 75 baud or 10 5-bit characters per second, and by the 1970s speeds of video terminals had improved to 2400 or 9600 2400 bit/s . Similarly, the speed of remote batch terminals had improved to 4800 bit/s at

4680-812: The last revision (the DECwriter IV of 1982) abandoning the classic teletypewriter form for one more resembling a desktop printer. A video display unit (VDU) displays information on a screen rather than printing text to paper and typically uses a cathode-ray tube (CRT). VDUs in the 1950s were typically designed for displaying graphical data rather than text and were used in, e.g., experimental computers at institutions like MIT ; computers used in academia, government and business, sold under brand names like DEC , ERA , IBM and UNIVAC ; military computers supporting specific defence applications such as ballistic missile warning systems and radar/air defence coordination systems like BUIC and SAGE . Two early landmarks in

4758-431: The later ADM and TVI models) did have a primitive block-send capability. Common early uses of local processing power included features that had little to do with off-loading data processing from the host computer but added useful features such as printing to a local printer, buffered serial data transmission and serial handshaking (to accommodate higher serial transfer speeds), and more sophisticated character attributes for

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4836-404: The multiplexer and the host, while the 2260 used either a channel connection or asynchronous serial communication between the 2848 and the host. The 2265, related to the 2260, also used asynchronous serial communication. The Datapoint 3300 from Computer Terminal Corporation , announced in 1967 and shipped in 1969, was a character-mode device that emulated a Model 33 Teletype . This reflects

4914-407: The operator attempted to enter more data into the field than allowed. A graphical terminal can display images as well as text. Graphical terminals are divided into vector-mode terminals, and raster mode . A vector-mode display directly draws lines on the face of a cathode-ray tube under control of the host computer system. The lines are continuously formed, but since the speed of electronics

4992-417: The original IRIX 6.5 code, and a feature release (with an "f" suffix) that includes improvements and enhancements. An overlay upgrade from 6.5.x to the 6.5.22 maintenance release was available as a free download, whereas versions 6.5.23 and higher required an active Silicon Graphics support contract. A 2001 Computerworld review found IRIX in a "critical" state. SGI had been moving its efforts to Linux and

5070-475: The release number prefixed by "4D1-", such as "4D1-2.2". The "4D1-" prefix continued to be used in official documentation to prefix IRIX release numbers. Prior to the IRIS 4D, SGI bundled the GL2 operating system, based on UniSoft UniPlus System V Unix , and using the proprietary MEX (Multiple EXposure) windowing system . IRIX 3.x is based on UNIX System V Release 3 with 4.3BSD enhancements, and incorporates

5148-472: The same limited functionality as does a mechanical Teletype. This type of dumb terminal is still supported on modern Unix-like systems by setting the environment variable TERM to dumb . Smart or intelligent terminals are those that also have the ability to process escape sequences, in particular the VT52, VT100 or ANSI escape sequences. A text terminal , or often just terminal (sometimes text console )

5226-413: The screen usually causes the terminal to scroll down one line, entering data into the last screen position on a block-oriented terminal usually causes the cursor to wrap — move to the start of the first enterable field. Programmers might "protect" the last screen position to prevent inadvertent wrap. Likewise a protected field following an enterable field might lock the keyboard and sound an audible alarm if

5304-415: The simplest form, a text terminal is like a file. Writing to the file displays the text and reading from the file produces what the user enters. In Unix-like operating systems, there are several character special files that correspond to available text terminals. For other operations, there are special escape sequences , control characters and termios functions that a program can use, most easily via

5382-494: The structure of the document, but later word processors operate in a graphical environment and provide a WYSIWYG simulation of the formatted output. However, text editors are still used for documents containing markup such as DocBook or LaTeX . Programs such as Telix and Minicom control a modem and the local terminal to let the user interact with remote servers. On the Internet , telnet and ssh work similarly. In

5460-511: The technique of storing context information for the transaction in progress on the screen, possibly in a hidden field, rather than depending on a running program to keep track of status. This was the precursor of the HTML technique of storing context in the URL as data to be passed as arguments to a CGI program. Unlike a character-oriented terminal, where typing a character into the last position of

5538-474: The term "glass TTY" tended to be restrospectively narrowed to devices without full cursor addressibility. The classic era of the VDU began in the early 1970s and was closely intertwined with the rise of time sharing computers . Important early products were the ADM-3A , VT52 , and VT100 . These devices used no complicated CPU , instead relying on individual logic gates , LSI chips, or microprocessors such as

5616-439: The two protocols are incompatible and may result in damage to the keyboard, computer, or both. An easy method to determine if a Silicon Graphics keyboard is PS/2 or not is to check whether or not the mouse plugs in to the keyboard - the IRIS protocol, similar to Apple 's Apple Desktop Bus and Sun's own serial keyboard/mouse protocol, daisy-chains the mouse and keyboard together. Computer terminal A computer terminal

5694-417: The year 2000, the hardware computer terminal was nearly obsolete. A character-oriented terminal is a type of computer terminal that communicates with its host one character at a time, as opposed to a block-oriented terminal that communicates in blocks of data. It is the most common type of data terminal, because it is easy to implement and program. Connection to the mainframe computer or terminal server

5772-603: Was a Friden Flexowriter , which would continue to serve this purpose on many other early computers well into the 1960s. Early user terminals connected to computers were, like the Flexowriter, electromechanical teleprinters /teletypewriters (TeleTYpewriter, TTY), such as the Teletype Model ;33 , originally used for telegraphy ; early Teletypes were typically configured as Keyboard Send-Receive (KSR) or Automatic Send-Receive (ASR). Some terminals, such as

5850-499: Was claimed to reduce eye strain). Terminals with modest color capability were also available but not widely used; for example, a color version of the popular Wyse WY50, the WY350, offered 64 shades on each character cell. VDUs were eventually displaced from most applications by networked personal computers, at first slowly after 1985 and with increasing speed in the 1990s. However, they had a lasting influence on PCs. The keyboard layout of

5928-510: Was marketed as "Cellular IRIX", although it only incorporates some features from the original Cellular IRIX distributed operating system project. The last major version of IRIX is 6.5, released in May 1998. New minor versions of IRIX 6.5 were released every quarter until 2005, and then four minor releases. Through version 6.5.22, there are two branches of each release: a maintenance release (identified by an "m" suffix) that includes only fixes to

6006-413: Was purchased by Rackable Systems , which was later purchased by Hewlett Packard Enterprise in 2016. All SGI hardware produced after 2007 is based on either IA-64 or x86-64 architecture, so it is incapable of running IRIX and is instead intended for Red Hat Enterprise Linux or SUSE Linux Enterprise Server . HPE has not stated any plans for IRIX development or source code release. IRIX 6.5

6084-457: Was the 4D/60 'Professional IRIS', sporting a MIPS R2300 clocked at 8 MHz in a unique 'twin-tower' case, with the cardcage being within the larger tower on the left, and the power supply and drives being kept within the smaller tower on the right. The right tower could come in different heights to support larger quantities of storage. Like the IRIS 1000 series which preceded it, the 4D/60 did not use an internally designed processor board, instead using

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