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78-429: An RTU monitors the field digital and analog parameters and transmits data to a SCADA Master Station. It runs setup software to connect data input streams to data output streams, define communication protocols, and troubleshoot installation problems in the field. An RTU may consist of one complex circuit card consisting of various sections needed to do a custom-fitted function, or may consist of many circuit cards including

156-435: A ROM cartridge. BASIC declined in popularity in the 1990s, as more powerful microcomputers came to market and programming languages with advanced features (such as Pascal and C ) became tenable on such computers. By then, most nontechnical personal computer users relied on pre-written applications rather than writing their own programs. In 1991, Microsoft released Visual Basic , combining an updated version of BASIC with

234-519: A sigil , and values are often identified as strings by being delimited by "double quotation marks". Arrays in BASIC could contain integers, floating point or string variables. Some dialects of BASIC supported matrices and matrix operations , which can be used to solve sets of simultaneous linear algebraic equations. These dialects would directly support matrix operations such as assignment, addition, multiplication (of compatible matrix types), and evaluation of

312-519: A visual forms builder . This reignited use of the language and "VB" remains a major programming language in the form of VB.NET , while a hobbyist scene for BASIC more broadly continues to exist. John G. Kemeny was the chairman of the Dartmouth College Mathematics Department. Based largely on his reputation as an innovator in math teaching, in 1959 the college won an Alfred P. Sloan Foundation award for $ 500,000 to build

390-742: A $ 300,000 grant from the National Science Foundation , which was used to purchase a GE-225 computer for processing, and a Datanet-30 realtime processor to handle the Teletype Model 33 teleprinters used for input and output. A team of a dozen undergraduates worked on the project for about a year, writing both the DTSS system and the BASIC compiler. The first version BASIC language was released on 1 May 1964. Initially, BASIC concentrated on supporting straightforward mathematical work, with matrix arithmetic support from its initial implementation as

468-669: A BASIC for the PDP-8 , which was a major success in the education market. By the early 1970s, FOCAL and JOSS had been forgotten and BASIC had become almost universal in the minicomputer market. DEC would go on to introduce their updated version, BASIC-PLUS , for use on the RSTS/E time-sharing operating system. During this period a number of simple text-based games were written in BASIC, most notably Mike Mayfield's Star Trek . David Ahl collected these, some ported from FOCAL, and published them in an educational newsletter he compiled. He later collected

546-433: A CPU or processing with communications interface(s), and one or more of the following: (AI) analog input, (DI) digital (status) input, (DO/CO) digital (or control relay) output, or (AO) analog output card(s). An RTU might even be a small process control unit with a small database for PID, Alarming, Filtering, Trending and other functions complemented with some BASIC (programming language) tasks. Modern RTUs typically support

624-472: A batch language, and character string functionality being added by 1965. Usage in the university rapidly expanded, requiring the main CPU to be replaced by a GE-235, and still later by a GE-635. By the early 1970s there were hundreds of terminals connected to the machines at Dartmouth, some of them remotely. Wanting use of the language to become widespread, its designers made the compiler available free of charge. In

702-460: A communication system from a master or IED ( intelligent electronic device ) sending data values to it. The RTU or host system translates and scales this raw data into the appropriate units such as the quantity of water left, temperature degrees, or Megawatts, before presenting the data to the user via the human–machine interface . RTUs may drive high current capacity relays to a digital output (or "DO") board to switch power on and off to devices in

780-466: A determinant. Many microcomputer BASICs did not support this data type; matrix operations were still possible, but had to be programmed explicitly on array elements. New BASIC programmers on a home computer might start with a simple program, perhaps using the language's PRINT statement to display a message on the screen; a well-known and often-replicated example is Kernighan and Ritchie 's "Hello, World!" program : An infinite loop could be used to fill

858-539: A larger control system or a data collection system (incorporated into a larger system). Data may be moved using a copper, fibre optic or radio frequency communication system. 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

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936-410: A loop: DO 100 , I = 1 , 10 , 2 . Is it '1, 10, 2' or '1, 2, 10', and is the comma after the line number required or not?" Moreover, the lack of any sort of immediate feedback was a key problem; the machines of the era used batch processing and took a long time to complete a run of a program. While Kurtz was visiting MIT , John McCarthy suggested that time-sharing offered a solution;

1014-455: A machine capable of running between 16 and 32 users at the same time. The system, bundled as the HP 2000, was the first mini platform to offer time-sharing and was an immediate runaway success, catapulting HP to become the third-largest vendor in the minicomputer space, behind DEC and Data General (DG). DEC, the leader in the minicomputer space since the mid-1960s, had initially ignored BASIC. This

1092-466: A master SCADA system and output for display locally or remotely, wherever needed. Modern RTUs are usually capable of executing simple programs autonomously without involving the host computers of the DCS or SCADA system to simplify deployment and to provide redundancy for safety reasons. An RTU in a modern water management system will typically have code to modify its behavior when physical override switches on

1170-511: A microprocessor to perform several protective, control and similar functions. A typical IED can contain around 5–12 protection functions, 5–8 control functions controlling separate devices, an autoreclose function, self monitoring function, communication functions etc. Some recent IEDs are designed to support the IEC61850 standard for substation automation, which provides interoperability and advanced communications capabilities. IEDs are used as

1248-496: A more modern alternative to, or a complement of, setup with traditional remote terminal units (RTUs). Unlike the RTUs, IEDs are integrated with the devices they control and offer a standardized set of measuring and control points that is easier to configure and require less wiring. Most IEDs have a communication port and built-in support for standard communication protocols ( DNP3 , IEC104 or IEC61850), so they can communicate directly with

1326-467: A multi-drop configuration. In this type of configuration it is a remote unit that collects data and performs simple control tasks. It does not have moving parts and uses extremely low power and is often solar powered. A form of power supply will be included for operation from the AC mains for various CPU, status wetting voltages and other interface cards. This may consist of AC to DC converters where operated from

1404-417: A new department building. Thomas E. Kurtz had joined the department in 1956, and from the 1960s Kemeny and Kurtz agreed on the need for programming literacy among students outside the traditional STEM fields. Kemeny later noted that "Our vision was that every student on campus should have access to a computer , and any faculty member should be able to use a computer in the classroom whenever appropriate. It

1482-433: A number of these into book form, 101 BASIC Computer Games , published in 1973. During the same period, Ahl was involved in the creation of a small computer for education use, an early personal computer . When management refused to support the concept, Ahl left DEC in 1974 to found the seminal computer magazine, Creative Computing . The book remained popular, and was re-published on several occasions. The introduction of

1560-591: A periodic basis. Analog value changes will usually be reported only on changes outside a set limit from the last transmitted value. Digital (status) values observe a similar technique and only transmit groups (bytes) when one included point (bit) changes. Another method used is where a subordinate unit initiates an update of data upon a predetermined change in analog or digital data. Complete data transmission must be performed periodically, with either method, to ensure full synchronization and eliminate stale data. Most communication protocols support both methods, programmable by

1638-401: A prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration", BASIC was one of the few languages that was both high-level enough to be usable by those without training and small enough to fit into the microcomputers of the day, making it the de facto standard programming language on early microcomputers. The first microcomputer version of BASIC

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1716-621: A remote contact (open or closed) at the RTU site. This contact position may represent many different devices, including electrical breakers, liquid valve positions, alarm conditions, and mechanical positions of devices. Counter inputs are optional. An RTU can monitor analog inputs of different types including 0-1 mA, 4–20 mA current loop , 0–10 V., ±2.5 V, ±5.0 V etc. Many RTU inputs buffer larger quantities via transducers to convert and isolate real-world quantities from sensitive RTU input levels. An RTU can also receive analog data via

1794-463: A single machine could divide up its processing time among many users, giving them the illusion of having a (slow) computer to themselves. Small programs would return results in a few seconds. This led to increasing interest in a system using time-sharing and a new language specifically for use by non-STEM students. Kemeny wrote the first version of BASIC. The acronym BASIC comes from the name of an unpublished paper by Thomas Kurtz. The new language

1872-406: A smaller introductory version with the initial releases of the machines and a Microsoft-based version introduced as interest in the platforms increased. As new companies entered the field, additional versions were added that subtly changed the BASIC family. The Atari 8-bit computers use the 8 KB Atari BASIC which is not derived from Microsoft BASIC. Sinclair BASIC was introduced in 1980 with

1950-404: A station battery system. RTUs may include a battery and charger circuitry to continue operation in event of AC power failure for critical applications where a station battery is not available. Most RTUs incorporate an input section or input status cards to acquire two state real-world information. This is usually accomplished by using an isolated voltage or current source to sense the position of

2028-556: A version of the MS code, or quickly introduced new models with it. Ohio Scientific's personal computers also joined this trend at that time. By 1978, MS BASIC was a de facto standard and practically every home computer of the 1980s included it in ROM . Upon boot, a BASIC interpreter in direct mode was presented. Commodore Business Machines includes Commodore BASIC , based on Microsoft BASIC. The Apple II and TRS-80 each have two versions of BASIC:

2106-554: A wide variety of Tiny BASICs with added features or other improvements, with versions from Tom Pittman and Li-Chen Wang becoming particularly well known. Micro-Soft, by this time Microsoft , ported their interpreter for the MOS 6502 , which quickly become one of the most popular microprocessors of the 8-bit era. When new microcomputers began to appear, notably the "1977 trinity" of the TRS-80 , Commodore PET and Apple II , they either included

2184-571: Is one of the languages that can be accessed by the 4Dos, 4NT, and Take Command enhanced shells. SaxBasic and WWB are also very similar to the Visual Basic line of Basic implementations. The pre-Office 97 macro language for Microsoft Word is known as WordBASIC . Excel 4 and 5 use Visual Basic itself as a macro language. Chipmunk Basic , an old-school interpreter similar to BASICs of the 1970s, is available for Linux , Microsoft Windows and macOS . The ubiquity of BASIC interpreters on personal computers

2262-487: Is very similar to VBA 6. The Host Explorer terminal emulator uses WWB as a macro language; or more recently the programme and the suite in which it is contained is programmable in an in-house Basic variant known as Hummingbird Basic. The VBScript variant is used for programming web content, Outlook 97, Internet Explorer, and the Windows Script Host. WSH also has a Visual Basic for Applications (VBA) engine installed as

2340-621: Is written for GW-BASIC, but will work in most versions of BASIC with minimal changes: The resulting dialog might resemble: Intelligent electronic device In the electric power industry , an intelligent electronic device ( IED ) is an integrated microprocessor -based controller of power system equipment, such as circuit breakers , transformers and capacitor banks. IEDs receive data from sensors and power equipment and can issue control commands, such as tripping circuit breakers if they sense voltage , current , or frequency anomalies, or raise/lower tap positions in order to maintain

2418-504: The Apple Macintosh , while yab is a version of yaBasic optimized for BeOS , ZETA and Haiku . These later variations introduced many extensions, such as improved string manipulation and graphics support, access to the file system and additional data types . More important were the facilities for structured programming , including additional control structures and proper subroutines supporting local variables . However, by

Remote terminal unit - Misplaced Pages Continue

2496-556: The IEC 61131-3 programming standard for programmable logic controllers. Since RTUs may be routinely deployed in pipeline and grid guarding systems, or in other hard-to-reach or extreme environments (for example in the Biosphere 2 project), they are required to operate under harsh conditions, and implement energy-saving measures (such as switching off IO modules when not in use). For example, it communicates via RS485 or wireless communication links in

2574-523: The Nintendo 3DS and Nintendo DSi called Petit Computer allows for programming in a slightly modified version of BASIC with DS button support. A version has also been released for Nintendo Switch , which has also been supplied a version of the Fuze Code System, a BASIC variant first implemented as a custom Raspberry Pi machine. Previously BASIC was made available on consoles as Family BASIC (for

2652-522: The Nintendo Famicom ) and PSX Chipmunk Basic (for the original PlayStation ), while yabasic was ported to the PlayStation 2 and FreeBASIC to the original Xbox . Variants of BASIC are available on graphing and otherwise programmable calculators made by Texas Instruments ( TI-BASIC ), HP ( HP BASIC ), Casio ( Casio BASIC ), and others. QBasic , a version of Microsoft QuickBASIC without

2730-561: 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 history to one of these versions of BASIC. The emergence of microcomputers in the mid-1970s led to the development of multiple BASIC dialects, including Microsoft BASIC in 1975. Due to

2808-943: The QB64 and FreeBASIC implementations. In 2013 a game written in QBasic and compiled with QB64 for modern computers entitled Black Annex was released on Steam . Blitz Basic , Dark Basic , SdlBasic , Super Game System Basic , PlayBASIC , CoolBasic , AllegroBASIC , ethosBASIC , GLBasic and Basic4GL further filled this demand, right up to the modern RCBasic , NaaLaa , AppGameKit , Monkey 2 and Cerberus-X . In 1991, Microsoft introduced Visual Basic , an evolutionary development of QuickBASIC . It included constructs from that language such as block-structured control statements, parameterized subroutines and optional static typing as well as object-oriented constructs from other languages such as "With" and "For Each". The language retained some compatibility with its predecessors, such as

2886-486: The 1960s, software became a chargeable commodity; until then, it was provided without charge as a service with expensive computers, usually available only to lease. They also made it available to high schools in the Hanover, New Hampshire , area and regionally throughout New England on Teletype Model 33 and Model 35 teleprinter terminals connected to Dartmouth via dial-up phone lines, and they put considerable effort into promoting

2964-561: The BASIC language with a day of events on April 30, 2014. A short documentary film was produced for the event. Minimal versions of BASIC had only integer variables and one- or two-letter variable names, which minimized requirements of limited and expensive memory (RAM). More powerful versions had floating-point arithmetic, and variables could be labelled with names six or more characters long. There were some problems and restrictions in early implementations; for example, Applesoft BASIC allowed variable names to be several characters long, but only

3042-501: The DO was instead indicated by the NEXT I . Likewise, the cryptic IF statement of Fortran, whose syntax matched a particular instruction of the machine on which it was originally written, became the simpler IF I = 5 THEN GOTO 100 . These changes made the language much less idiosyncratic while still having an overall structure and feel similar to the original FORTRAN. The project received

3120-494: The Dim keyword for declarations, "Gosub"/Return statements and optional line numbers which could be used to locate errors. An important driver for the development of Visual Basic was as the new macro language for Microsoft Excel , a spreadsheet program. To the surprise of many at Microsoft who still initially marketed it as a language for hobbyists, the language came into widespread use for small custom business applications shortly after

3198-1009: The RTU are toggled during maintenance by maintenance personnel. This is done for safety reasons; a miscommunication between the system operators and the maintenance personnel could cause system operators to mistakenly enable power to a water pump when it is being replaced, for example. Maintenance personnel should have any equipment they are working on disconnected from power and locked to prevent damage and/or injury. An RTU may be interfaced to multiple master stations and IEDs ( Intelligent Electronic Devices ) with different communication protocols (usually serial ( RS-232 , RS-485 , RS-422 ) or Ethernet ). An RTU may support standard protocols ( Modbus , IEC 60870-5 -101/103/104, DNP3 , IEC 60870-6 -ICCP, IEC 61850 etc.) to interface any third party software. Data transfer may be initiated from either end using various techniques to ensure synchronization with minimal data traffic. The master may poll its subordinate unit (Master to RTU or RTU to IED) for changes of data on

Remote terminal unit - Misplaced Pages Continue

3276-619: The Sinclair ZX80 , and was later extended for the Sinclair ZX81 and the Sinclair ZX Spectrum . The BBC published BBC BASIC , developed by Acorn Computers , incorporates extra structured programming keywords and floating-point features. As the popularity of BASIC grew in this period, computer magazines published complete source code in BASIC for video games, utilities, and other programs. Given BASIC's straightforward nature, it

3354-403: The article prompted Microsoft to develop and release Small Basic ; it also inspired similar projects like Basic-256 and the web based Quite Basic. Dartmouth held a 50th anniversary celebration for BASIC on 1 May 2014. The pedagogical use of BASIC has been followed by other languages, such as Pascal , Java and particularly Python . Dartmouth College celebrated the 50th anniversary of

3432-461: The blink of an eye" even using a "slow" language, as long as large amounts of data were not involved. Many small business owners found they could create their own small, yet useful applications in a few evenings to meet their own specialized needs. Eventually, during the lengthy lifetime of VB3, knowledge of Visual Basic had become a marketable job skill. Microsoft also produced VBScript in 1996 and Visual Basic .NET in 2001. The latter has essentially

3510-505: The business-focused CP/M computers which soon became widespread in small business environments, Microsoft BASIC ( MBASIC ) was one of the leading applications. In 1978, David Lien published the first edition of The BASIC Handbook: An Encyclopedia of the BASIC Computer Language , documenting keywords across over 78 different computers. By 1981, the second edition documented keywords from over 250 different computers, showcasing

3588-419: The desired voltage level. Common types of IEDs include protective relaying devices, tap changer controllers, circuit breaker controllers, capacitor bank switches, recloser controllers, voltage regulators etc. This is generally controlled by a setting file. The testing of setting files is typically one of the most time-consuming roles of a protection tester. Digital protective relays are primarily IEDs, using

3666-486: The display with the message: Note that the END statement is optional and has no action in most dialects of BASIC. It was not always included, as is the case in this example. This same program can be modified to print a fixed number of messages using the common FOR...NEXT statement: Most home computers BASIC versions, such as MSX BASIC and GW-BASIC , supported simple data types, loop cycles, and arrays. The following example

3744-449: The emerging field quickly followed suit; Tymshare introduced SUPER BASIC in 1968, CompuServe had a version on the DEC-10 at their launch in 1969, and by the early 1970s BASIC was largely universal on general-purpose mainframe computers . Even IBM eventually joined the club with the introduction of VS-BASIC in 1973. Although time-sharing services with BASIC were successful for a time,

3822-541: The explosive growth of the microcomputer era. When IBM was designing the IBM PC , they followed the paradigm of existing home computers in having a built-in BASIC interpreter. They sourced this from Microsoft – IBM Cassette BASIC – but Microsoft also produced several other versions of BASIC for MS-DOS / PC DOS including IBM Disk BASIC (BASIC D), IBM BASICA (BASIC A), GW-BASIC (a BASICA-compatible version that did not need IBM's ROM) and QBasic , all typically bundled with

3900-530: The field. The DO board switches voltage to the coil in the relay, which closes the high current contacts, which completes the power circuit to the device. RTU outputs may also consist of driving a sensitive logic input on an electronic PLC , or other electronic device using a sensitive 5 V input. While not as commonly used, analog outputs may be included to control devices that require varying quantities, such as graphic recording instruments (strip charts). Summed or processed data quantities may be generated in

3978-536: The final version 6.0 of the original Visual Basic ended on March 31, 2005, followed by extended support in March 2008. Owing to its persistent remaining popularity, third-party attempts to further support it exist. On February 2, 2017, Microsoft announced that development on VB.NET would no longer be in parallel with that of C#, and on March 11, 2020, it was announced that evolution of the VB.NET language had also concluded. Even so,

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4056-406: The first microcomputers in the mid-1970s was the start of explosive growth for BASIC. It had the advantage that it was fairly well known to the young designers and computer hobbyists who took an interest in microcomputers, many of whom had seen BASIC on minis or mainframes. Despite Dijkstra 's famous judgement in 1975, "It is practically impossible to teach good programming to students that have had

4134-489: The first two were significant, thus it was possible to inadvertently write a program with variables "LOSS" and "LOAN", which would be treated as being the same; assigning a value to "LOAN" would silently overwrite the value intended as "LOSS". Keywords could not be used in variables in many early BASICs; "SCORE" would be interpreted as "SC" OR "E", where OR was a keyword. String variables are usually distinguished in many microcomputer dialects by having $ suffixed to their name as

4212-506: The installer. Multiple RTUs or IEDs may share a communications line, in a multi-drop scheme , as units are addressed uniquely and only respond to their own polls and commands. IED communications transfer data between the RTU and an IED (Intelligent Electronic Devices) . This can eliminate the need for many hardware status inputs, analog inputs, and relay outputs in the RTU. Communications are accomplished by copper or fibre optics lines . Master communications usually occur between an RTU and

4290-869: The language was still supported. Many other BASIC dialects have also sprung up since 1990, including the open source QB64 and FreeBASIC , inspired by QBasic, and the Visual Basic-styled RapidQ , HBasic , Basic For Qt and Gambas . Modern commercial incarnations include PureBasic , PowerBASIC , Xojo , Monkey X and True BASIC (the direct successor to Dartmouth BASIC from a company controlled by Kurtz). Several web-based simple BASIC interpreters also now exist, including Microsoft's Small Basic and Google 's wwwBASIC. A number of compilers also exist that convert BASIC into JavaScript . such as NS Basic . Building from earlier efforts such as Mobile Basic , many dialects are now available for smartphones and tablets. On game consoles, an application for

4368-498: The language. How to design and implement a stripped-down version of an interpreter for the BASIC language was covered in articles by Allison in the first three quarterly issues of the People's Computer Company newsletter published in 1975 and implementations with source code published in Dr. Dobb's Journal of Tiny BASIC Calisthenics & Orthodontia: Running Light Without Overbyte . This led to

4446-509: The language. In the following years, as other dialects of BASIC appeared, Kemeny and Kurtz's original BASIC dialect became known as Dartmouth BASIC . New Hampshire recognized the accomplishment in 2019 when it erected a highway historical marker in Hanover describing the creation of "the first user-friendly programming language". The emergence of BASIC took place as part of a wider movement toward time-sharing systems. First conceptualized during

4524-563: The late 1950s, the idea became so dominant in the computer industry by the early 1960s that its proponents were speaking of a future in which users would "buy time on the computer much the same way that the average household buys power and water from utility companies". General Electric, having worked on the Dartmouth project, wrote their own underlying operating system and launched an online time-sharing system known as Mark I. It featured BASIC as one of its primary selling points. Other companies in

4602-403: The latter half of the 1980s, users were increasingly using pre-made applications written by others rather than learning programming themselves; while professional programmers now had a wide range of more advanced languages available on small computers. C and later C++ became the languages of choice for professional "shrink wrap" application development. A niche that BASIC continued to fill

4680-524: The linker to make EXE files, is present in the Windows NT and DOS- Windows 95 streams of operating systems and can be obtained for more recent releases like Windows 7 which do not have them. Prior to DOS 5, the Basic interpreter was GW-Basic . QuickBasic is part of a series of three languages issued by Microsoft for the home and office power user and small-scale professional development; QuickC and QuickPascal are

4758-685: The machine. In addition they produced the Microsoft BASIC Compiler aimed at professional programmers. Turbo Pascal -publisher Borland published Turbo Basic 1.0 in 1985 (successor versions are still being marketed under the name PowerBASIC ). On Unix-like systems, specialized implementations were created such as XBasic and X11-Basic . XBasic was ported to Microsoft Windows as XBLite , and cross-platform variants such as SmallBasic , yabasic , Bywater BASIC , nuBasic , MyBasic , Logic Basic , Liberty BASIC , and wxBasic emerged. FutureBASIC and Chipmunk Basic meanwhile targeted

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4836-580: The original 101 BASIC games converted into the Microsoft dialect and published it from Creative Computing as BASIC Computer Games . This book, and its sequels, provided hundreds of ready-to-go programs that could be easily converted to practically any BASIC-running platform. The book reached the stores in 1978, just as the home computer market was starting off, and it became the first million-selling computer book. Later packages, such as Learn to Program BASIC would also have gaming as an introductory focus. On

4914-446: The other two. For Windows 95 and 98, which do not have QBasic installed by default, they can be copied from the installation disc, which will have a set of directories for old and optional software; other missing commands like Exe2Bin and others are in these same directories. The various Microsoft, Lotus, and Corel office suites and related products are programmable with Visual Basic in one form or another, including LotusScript , which

4992-426: The release of VB version 3.0, which is widely considered the first relatively stable version. Microsoft also spun it off as Visual Basic for Applications and Embedded Visual Basic . While many advanced programmers still scoffed at its use, VB met the needs of small businesses efficiently as by that time, computers running Windows 3.1 had become fast enough that many business-related processes could be completed "in

5070-440: The same power as C# and Java but with syntax that reflects the original Basic language, and also features some cross-platform capability through implementations such as Mono-Basic . The IDE , with its event-driven GUI builder , was also influential on other rapid application development tools, most notably Borland Software 's Delphi for Object Pascal and its own descendants such as Lazarus . Mainstream support for

5148-452: The third of the default engines along with VBScript, JScript, and the numerous proprietary or open source engines which can be installed like PerlScript , a couple of Rexx-based engines, Python, Ruby, Tcl, Delphi, XLNT, PHP, and others; meaning that the two versions of Basic can be used along with the other mentioned languages, as well as LotusScript, in a WSF file, through the component object model, and other WSH and VBA constructions. VBScript

5226-472: The time, nearly all computers required writing custom software, which only scientists and mathematicians tended to learn. In addition to the programming 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 popular on minicomputer systems like

5304-407: The tiny main memory available on these machines, often 4 KB, a variety of Tiny BASIC dialects were also created. BASIC was available for almost any system of the era, and became the de facto programming language for home computer systems that emerged in the late 1970s. These PCs almost always had a BASIC interpreter installed by default, often in the machine's firmware or sometimes on

5382-412: The widespread success predicted earlier was not to be. The emergence of minicomputers during the same period, and especially low-cost microcomputers in the mid-1970s, allowed anyone to purchase and run their own systems rather than buy online time which was typically billed at dollars per minute. BASIC, by its very nature of being small, was naturally suited to porting to the minicomputer market, which

5460-466: Was HP Time-Shared BASIC , which, like the original Dartmouth system, used two computers working together to implement a time-sharing system. The first, a low-end machine in the HP 2100 series, was used to control user input and save and load their programs to tape or disk. The other, a high-end version of the same underlying machine, ran the programs and generated output. For a cost of about $ 100,000, one could own

5538-407: Was a simple matter to type in the code from the magazine and execute the program. Different magazines were published featuring programs for specific computers, though some BASIC programs were considered universal and could be used in machines running any variant of BASIC (sometimes with minor adaptations). Many books of type-in programs were also available, and in particular, Ahl published versions of

5616-515: Was as simple as that." Kemeny and Kurtz had made two previous experiments with simplified languages, DARSIMCO (Dartmouth Simplified Code) and DOPE (Dartmouth Oversimplified Programming Experiment) . These did not progress past a single freshman class. New experiments using Fortran and ALGOL followed, but Kurtz concluded these languages were too tricky for what they desired. As Kurtz noted, Fortran had numerous oddly formed commands, notably an "almost impossible-to-memorize convention for specifying

5694-805: Was co-written by Bill Gates , Paul Allen and Monte Davidoff for their newly formed company, Micro-Soft. This was released by MITS in punch tape format for the Altair 8800 shortly after the machine itself, immediately cementing BASIC as the primary language of early microcomputers. Members of the Homebrew Computer Club began circulating copies of the program, causing Gates to write his Open Letter to Hobbyists , complaining about this early example of software piracy . Partially in response to Gates's letter, and partially to make an even smaller BASIC that would run usefully on 4 KB machines, Bob Albrecht urged Dennis Allison to write their own variation of

5772-542: Was due to their work with RAND Corporation , who had purchased a PDP-6 to run their JOSS language, which was conceptually very similar to BASIC. This led DEC to introduce a smaller, cleaned up version of JOSS known as FOCAL , which they heavily promoted in the late 1960s. However, with timesharing systems widely offering BASIC, and all of their competition in the minicomputer space doing the same, DEC's customers were clamoring for BASIC. After management repeatedly ignored their pleas, David H. Ahl took it upon himself to buy

5850-415: Was emerging at the same time as the time-sharing services. These machines had small main memory , perhaps as little as 4 KB in modern terminology, and lacked high-performance storage like hard drives that make compilers practical. On these systems, BASIC was normally implemented as an interpreter rather than a compiler due to its lower requirement for working memory. A particularly important example

5928-499: Was for hobbyist video game development , as game creation systems and readily available game engines were still in their infancy. The Atari ST had STOS BASIC while the Amiga had AMOS BASIC for this purpose. Microsoft first exhibited BASIC for game development with DONKEY.BAS for GW-BASIC , and later GORILLA.BAS and NIBBLES.BAS for QuickBASIC . QBasic maintained an active game development community, which helped later spawn

6006-419: Was heavily patterned on FORTRAN II; statements were one-to-a-line, numbers were used to indicate the target of loops and branches, and many of the commands were similar or identical to Fortran. However, the syntax was changed wherever it could be improved. For instance, the difficult to remember DO loop was replaced by the much easier to remember FOR I = 1 TO 10 STEP 2 , and the line number used in

6084-437: Was such that textbooks once included simple "Try It In BASIC" exercises that encouraged students to experiment with mathematical and computational concepts on classroom or home computers. Popular computer magazines of the day typically included type-in programs . Futurist and sci-fi writer David Brin mourned the loss of ubiquitous BASIC in a 2006 Salon article as have others who first used computers during this era. In turn,

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