Calculator

Posts

Scientific calculator

A scientific calculator is a type of electronic calculator, usually but not always handheld, designed to calculate problems in science, engineering, and mathematics. They have almost completely replaced slide rules in almost all traditional applications, and are widely used in both education and professional settings. In certain contexts such as higher education, scientific calculators have been superseded by graphing calculators, which offer a superset of scientific calculator functionality along with the ability to graph input data and write and store programs for the device. There is also some overlap with the financial calculator market. Functions Modern scientific calculators generally have many more features than a standard four or five-function calculator, and the feature set differs between manufacturers and models; however, the defining features of a scientific calculator include: scientific notation floating point arithmetic logarithmic functions, usin...

Manufacturers

These are some of the manufacturers which made a notable contribution to calculator development: APF[40] – US Current manufacturers Aristo[40] (Dennert & Pape) - Germany Aurora – China Bell Punch Company[40] and ANITA – UK Bowmar[40] – US Braun - Germany Brunsviga[40] – Germany Burroughs[40] – US Busicom[40] – Japan Canon[40] – Japan Casio[40] – Japan Commodore[40] (CBM) – Canada/US Comptometer[40] and Felt & Tarrant – US Compucorp[40] – US Digitz – China Elektronika[40] – USSR Elite - Germany Facit[40] – Sweden Felt & Tarrant[40] – US →Comptometer Friden, Inc.[40] – US General Instrument[40] – US Hewlett-Packard[40] (HP) – US Hitachi[40] – Japan IME[40] – Italy Litronix[40] – US Lloyd's[40] – US MBO – Europe Marchant[40] – US Monroe[40] – US National Semiconductor[40] – US Nippon Calculating Machine[40] (NCM) – Japan →Busicom Novus[40] – US →National Semiconductor Odhner[40] – Russia and Sweden ...

Programmable calculators

The first desktop programmable calculators were produced in the mid-1960s by Mathatronics and Casio (AL-1000). These machines were very heavy and costly. The first programmable pocket calculator was the HP-65, in 1974; it had a capacity of 100 instructions, and could store and retrieve programs with a built-in magnetic card reader. Two years later the HP-25C introduced continuous memory, i.e., programs and data were retained in CMOS memory during power-off. In 1979, HP released the first alphanumeric, programmable, expandable calculator, the HP-41C. It could be expanded with random access memory (RAM, for memory) and read-only memory (ROM, for software) modules, and peripherals like bar code readers, microcassette and floppy disk drives, paper-roll thermal printers, and miscellaneous communication interfaces (RS-232, HP-IL, HP-IB). The first Soviet programmable desktop calculator ISKRA 123, powered by the power grid, was released at the start of the 1970s. The first Soviet p...

Pocket calculators

"Pocket calculator" redirects here. For the song, see Computer World. By 1970, a calculator could be made using just a few chips of low power consumption, allowing portable models powered from rechargeable batteries. The first portable calculators appeared in Japan in 1970, and were soon marketed around the world. These included the Sanyo ICC-0081 "Mini Calculator", the Canon Pocketronic, and the Sharp QT-8B "micro Compet". The Canon Pocketronic was a development of the "Cal-Tech" project which had been started at Texas Instruments in 1965 as a research project to produce a portable calculator. The Pocketronic has no traditional display; numerical output is on thermal paper tape. As a result of the "Cal-Tech" project, Texas Instruments was granted master patents on portable calculators. Sharp put in great efforts in size and power reduction and introduced in January 1971 the Sharp EL-8, also marketed as the Facit 1111, which was...

Development of electronic calculators

The first mainframe computers, using firstly vacuum tubes and later transistors in the logic circuits, appeared in the 1940s and 1950s. This technology was to provide a stepping stone to the development of electronic calculators. The Casio Computer Company, in Japan, released the Model 14-A calculator in 1957, which was the world's first all-electric (relatively) compact calculator. It did not use electronic logic but was based on relay technology, and was built into a desk. Early calculator light-emitting diode(LED) display from the 1970s (USSR). In October 1961, the world's first all-electronic desktop calculator, the British Bell Punch/Sumlock Comptometer ANITA (A New Inspiration To Arithmetic/Accounting) was announced. This machine used vacuum tubes, cold-cathode tubes and Dekatrons in its circuits, with 12 cold-cathode "Nixie" tubes for its display. Two models were displayed, the Mk VII for continental Europe and the Mk VIII for Britain and the res...

Calculators compared to computers

The fundamental difference between a calculator and computer is that a computer can be programmed in a way that allows the program to take different branches according to intermediate results, while calculators are pre-designed with specific functions (such as addition, multiplication, and logarithms) built in. The distinction is not clear-cut: some devices classed as programmable calculators have programming functions, sometimes with support for programming languages (such as RPL or TI-BASIC). Typically, the user buys the least costly model having a specific feature set, but does not care much about speed, since speed is constrained by how fast the user can press the buttons. Thus, designers of calculators work to minimize the number of logic elements on the chip, not the number of clock cycles needed to do a computation. For instance, instead of a hardware multiplier, a calculator might implement floating point mathematics with code in read-only memory (ROM), and compute trig...