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HP-71B
The HP-71B was a hand-held computer or calculator programmable in BASIC, made by Hewlett-Packard from 1984 to 1989. Description Smaller and less expensive (US$595 $525 in 1984 ≈ $990 in 2005 (seInflation Conversion Factors for Dollars) MSRP) than the preceding model HP-75, the 71B had a single-line 22-character liquid crystal display, 64K system ROM and 17.5K user memory. It operated on four AAA batteries. Four plug-in ports permitted ROM-based programs or additional user memory to be added. Separate compartments could accommodate an optional magnetic card reader and an optional HP-IL interface (HP 82401A) that could be used to connect printers, storage and electronic test equipment. The 71B was the first handheld to implement the IEEE 854-1987 radix-independent floating-point standard. Programming features included a real-time clock, programmable timers and subroutine calls with parameter passing and recursion. It was also HP's first calculator based on the ''Saturn'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturn (microprocessor)
The Saturn family of 4-bit (datapath) microprocessors was developed by Hewlett-Packard in the 1980s first for the HP-71B handheld computer and then later for various HP calculators (starting with the HP-18C). It succeeded the ''Nut'' family of processors used in earlier calculators. The original Saturn chip was first used in the HP-71B hand-held BASIC-programmable computer, introduced in 1984. Later models of the family powered the popular HP 48 series of calculators. The HP48SX and HP48S were the last models to use genuine Saturn processors manufactured by HP. Later calculator models used Saturn processors manufactured by NEC. The HP 49 series initially used the Saturn CPU as well, until the NEC fab could no longer manufacture the processor for technical reasons in 2003. Therefore, starting with the HP 49g+ model in 2003, the calculators switched to a Samsung S3C2410 processor with an ARM920T core (part of the ARMv4T architecture) which ran an emulator of the Saturn hardw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP-IL
The HP-IL (''Hewlett-Packard Interface Loop''), was a short-range interconnection bus or network introduced by Hewlett-Packard in the early 1980s. It enabled many devices such as printers, plotters, displays, storage devices (floppy disk drives and tape drives), test equipment, etc. to be connected to programmable calculators such as the HP-41C, HP-71B and HP-75C/D, the 80-series and HP-110 computers, as well as generic ISA bus based PCs. Principles As its name implies, an HP-IL network formed a loop (i.e. it was a Ring network): each device in the loop had a pair of two-wire connections, one designated ''in'', which received messages from the previous device in the loop; and one designated ''out'', which delivered messages to the next device in the loop. One device on the loop is designated the ''controller'', and manages all other devices on the loop. HP-IL cables utilize a unique two-pin connector design with polarizing "D"-shaped shells, and can be connected together ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP-41
The HP-41C series are programmable, expandable, continuous memory handheld RPN calculators made by Hewlett-Packard from 1979 to 1990. The original model, HP-41C, was the first of its kind to offer alphanumeric display capabilities. Later came the HP-41CV and HP-41CX, offering more memory and functionality. The alphanumeric "revolution" The alphanumeric LCD screen of the HP-41C revolutionized the way a pocket calculator could be used, providing user friendliness (for its time) and expandability (keyboard-unassigned functions could be spelled out alphabetically). By using an alphanumeric display, the calculator could tell the user what was going on: it could display error messages, such as showing ("DATA ERROR") upon attempting to divide by zero instead of simply displaying a blinking zero; it could also specifically prompt the user for arguments ("ENTER RADIUS") instead of just displaying a question mark. Earlier calculators needed a key, or key combination, for every a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP-75
The HP-75C and HP-75D were hand-held computers programmable in BASIC, made by Hewlett-Packard from 1982 to 1986. The HP-75 had a single-line liquid crystal display, 48 KiB system ROM and 16 KiB RAM, a comparatively large keyboard (albeit without a separate numeric pad), a manually operated magnetic card reader (2×650 bytes per card), 4 ports for memory expansion (1 for RAM and 3 for ROM modules), and an HP-IL interface that could be used to connect printers, storage and electronic test equipment. The BASIC interpreter also acted as a primitive operating system, providing file handling capabilities for program storage using RAM, cards, or cassettes/diskettes (via HP-IL). Other features included a text editor as well as an appointment reminder with alarms, similar to functions of modern PDAs. The HP-75D (1984–1986) added a port for a bar code wand, often used for inventory control tasks. The HP-75 was comparatively expensive with an MSRP of $995 ($2,014 in 2005) for the 75C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEEE 854-1987
The IEEE Standard for Radix-Independent Floating-Point Arithmetic (IEEE 854), was the first Institute of Electrical and Electronics Engineers (IEEE) international standard for floating-point arithmetic with radices other than 2, including radix 10. IEEE 854 did not specify any data formats, whereas IEEE 754-1985 did specify formats for binary (radix 2) floating point. IEEE 754-1985 and IEEE 854-1987 were both superseded in 2008 by IEEE 754-2008, which specifies floating-point arithmetic for both radix 2 (binary) and radix 10 (decimal), and specifies two alternative formats for radix 10 floating-point values, and even more so with IEEE 754-2019. IEEE 754-2008 also had many other updates to the IEEE floating-point standardisation. IEEE 854 arithmetic was first commercially implemented in the HP-71B The HP-71B was a hand-held computer or calculator programmable in BASIC, made by Hewlett-Packard from 1984 to 1989. Description Smaller and less expensive (US$595 $525 in 1984 ≈ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP Calculators
HP calculators are various calculators manufactured by the Hewlett-Packard company over the years. Their desktop models included the HP 9800 series, while their handheld models started with the HP-35. Their focus has been on high-end scientific, engineering and complex financial uses. History In the 1960s, Hewlett-Packard was becoming a diversified electronics company with product lines in electronic test equipment, scientific instrumentation, and medical electronics, and was just beginning its entry into computers. The corporation recognized two opportunities: it might be possible to automate the instrumentation that HP was producing, and HP's customer base were likely to buy a product that could replace the slide rules and adding machines that were being used for computation. With this in mind, HP built the HP 9100 desktop scientific calculator. This was a full-featured calculator that included not only standard "adding machine" functions but also powerful capabilities to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calculator Input Methods
There are various ways in which calculators interpret keystrokes. These can be categorized into two main types: * On a single-step or immediate-execution calculator, the user presses a key for each operation, calculating all the intermediate results, before the final value is shown. * On an expression or formula calculator, one types in an expression and then presses a key, such as "=" or "Enter", to evaluate the expression. There are various systems for typing in an expression, as described below. Immediate execution The immediate execution mode of operation (also known as single-step, algebraic entry system (AES) or chain calculation mode) is commonly employed on most general-purpose calculators. In most simple four-function calculators, such as the Windows Calculator, Windows calculator in Standard mode and those included with most early operating systems, each binary operation is executed as soon as the next operator is pressed, and therefore the order of operations in a math ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 the time, nearly all computers required writing custom software, which only scientists and mathematicians tended to learn. In addition to the program 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 very popular on minicomputer systems like 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hewlett-Packard
The Hewlett-Packard Company, commonly shortened to Hewlett-Packard ( ) or HP, was an American multinational information technology company headquartered in Palo Alto, California. HP developed and provided a wide variety of hardware components, as well as software and related services to consumers, small and medium-sized businesses ( SMBs), and large enterprises, including customers in the government, health, and education sectors. The company was founded in a one-car garage in Palo Alto by Bill Hewlett and David Packard in 1939, and initially produced a line of electronic test and measurement equipment. The HP Garage at 367 Addison Avenue is now designated an official California Historical Landmark, and is marked with a plaque calling it the "Birthplace of 'Silicon Valley'". The company won its first big contract in 1938 to provide test and measurement instruments for Walt Disney's production of the animated film ''Fantasia'', which allowed Hewlett and Packard to formally esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Crystal Display
A liquid-crystal display (LCD) is a flat panel display, flat-panel display or other Electro-optic modulator, electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directly but instead use a backlight or reflector (photography), reflector to produce images in color or monochrome monitor, monochrome. LCDs are available to display arbitrary images (as in a general-purpose computer display) or fixed images with low information content, which can be displayed or hidden. For instance: preset words, digits, and seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AAA Battery
The AAA battery (or triple-A battery) is a standard size of dry cell Battery (electricity), battery. One or more AAA batteries are commonly used in low-drain portable electronic devices. A zinc–carbon battery in this size is designated by International Electrotechnical Commission, IEC as R03, by ANSI C18.1 as 24, by old Japanese Industrial Standards, JIS standard as UM-4, and by other manufacturer and national standard designations that vary depending on the cell chemistry. The size was first introduced by Eveready Battery Company, The American Ever Ready Company in 1911. An AAA battery is a single cell that measures in diameter and in length, including the positive terminal button, which is a minimum . The positive terminal has a maximum diameter of ; the flat negative terminal has a minimum diameter of . Alkaline battery, Alkaline AAA batteries weigh around , while primary lithium battery, lithium AAA batteries weigh about . Rechargeable Nickel–metal hydride battery, n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP-48 Series
The HP 48 is a series of graphing calculators designed and produced by Hewlett-Packard from 1990 until 2003. The series includes the HP 48S, HP 48SX, HP 48G, HP 48GX, and HP 48G+, the G models being expanded and improved versions of the S models. The models with an X suffix are expandable via special RAM (memory expansion) and ROM (software application) cards. In particular, the GX models have more onboard memory than the G models. The G+ models have more onboard memory only. The SX and S models have the same amount of onboard memory. Note that the similarly named hp 48gII (2004) is not a member of the series but closely related to the HP 49G+. The calculators use Reverse Polish Notation (RPN) and the RPL programming language. The hardware architecture developed for the HP 48 series became the basis for the HP 38G, with a simplified user interface and an infix input method, and the HP 49G with various software enhancements. Lik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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