V.P.A.M. is an infix system for entering mathematical expressions, used by Casio in most of its current scientific calculators. In the infix notation the precedence of mathematical operators is taken into account. According to Casio, in V.P.A.M. calculations can be input exactly as they are normally written. Functions, operators and symbols are shown on the calculator display and calculations are performed according to operator precedence.
The V.P.A.M. brand was first used in 1994 when the fx-991S and other scientific calculators from the "S" series were released in Japan. In 1998, the Casio fx-991W model used a two-tier (multi-line) display and the system was termed as S-V.P.A.M. (Super V.P.A.M.). The model featured a 5×6-dot LCD matrix cells on the top line of the screen and a 7-segment LCD on the bottom line of the screen that had been used in Casio fx-4500P programmable calculators.[1] The S-V.P.A.M. system was also used in the other W series models and also the MS series of calculators that followed. V.P.A.M. is similar to the Direct Algebraic Logic (D.A.L.) used by Sharp in some of their scientific calculators.
The fx-82ES introduced by Casio in 2004 was the first calculator to incorporate the Natural Textbook Display (orNatural Display) system. It allowed the display of expressions of fractions, exponents, logarithms, powers and square roots etc. as they are written in a standard textbook. Natural Display uses natural representation of mathematical expressions and formulas through a 96×31 dot matrixLCD display. Casio uses the term Natural V.P.A.M. for the fx-ES Plus series of calculators which are the upgraded version of the fx-ES series.
In early 2015, Casio introduced a new line of calculators called ClassWiz (stylized as C L A S S W I Z) for different markets, featuring a high resolution (192×63) dot matrix Natural Textbook Display and incorporating spreadsheet functions in some models. This series of calculators is called the fx-EX series and it succeeds the fx-ES Plus series of calculators.
In late 2022, Casio introduced a second generation of ClassWiz line, called fx-CW. Calculators in this line have an updated user interface, and come with 4-gradation displays.[2]
2-line LCD display featuring 5×6-dot matrix cells top line and 7-segment LCD bottom line that had been used in Casio fx-4500P programmable calculators (used 5×7-dot matrix cells).[3]
Casio fx-115ES scientific calculator with Natural Display. (also called "Natural V.P.A.M." in the updated version)
Revised version of the MS Series including the following changes:
Multi-line 96×31 dot matrix displays, but character cells are connected by dots like graphing calculators
The ability to display and edit mathematical formulas in more visual formats
Revised design of function menu interface, previously featured in Casio fx-4800P[5]
No engineering symbol (SI prefixes) input or display facility, which was available in certain MS / W / S series models (fx-100, 115, 570 and 991MS / W / S).
Use the nX-U8/100 based OKI ML610901(B) microcontroller.
Casio fx-991EX ClassWiz (High-resolution Natural Textbook Display)Casio fx-991DE X, the German model of the fx-991EX, which contains more functions than the fx-991EX
The screen resolution remains at 192x63 pixels but now features 4-level grayscale display
Cursor navigation completely replaces the previous method of using numeric keys to select menu options
Added the Math Box application for mathematical exploration in most models
Significant changes to the keyboard layout: the ALPHA key is removed; navigation keys for cursor movement, page flipping, returning, and confirmation (OK) are added. However, the total number of keys is reduced from the original 50 to 48
Added Variable menu allows direct modification of variable values and supports storing results from the history log into variables
Added Function menu enables the definition of two functions and their utilization across multiple applications
Introduced CATALOG and TOOLS keys, where most functions and operations are accessed
The M variable is removed, replaced by the z variable
Except for CN CW models, variable store characters and multi-statement (i.e., colon ":") function are removed
Improved calculation precision to 23 digits and increased floating-point precision to 60 bits
The shutdown screen now includes not only the CASIO® logo but also the CASIO Education Statement slogan, Boost your Curiosity.[15] On the CN CW series, this slogan is additionally presented in Chinese as "激发你的好奇心"
The performance of the nX-U8/100 microprocessor is increased by approximately 1.6 times
The sliding protective cover is replaced with a snap-on cover
Model-specific features include:
The previous Verify mode is no longer a standalone mode but dispersed across multiple modes, accessible within the Calculate, Complex, Table, and Equation applications
The CALC function, present in most earlier models, has been removed from the majority of models except for the fx-880BTG and JP CW series
The SOLVE function becomes a part of the Equation application
When solving cubic equations, the capability to find local maximum and minimum values is supported
The Statistics application now supports data sorting
