Thursday, November 24, 2016

Retro Review: Casio fx-7400g Plus

Eddie’s Math and Calculator Blog:  Retro Review:  Casio fx-7400g Plus


Time:  Early 2000s, I have the early style where all the keys are rectangular
Screen:  48 x 80 pixels, 6 x 13 text
Power:  2 AA batteries with 2032 backup
Accuracy:  10 digits shown on screen, 15 digits internally
Memory:  20,000 bytes for programming (despite the 32K label on the calculator)

The calculator feels pretty good to hold, it is lightweight.

A Scaled Down fx-9850g

The fx-7400g Plus is a simplified version of fx-9850g family, marketed as entry level graphing calculator.  The features have been scaled down.  As a result the fx-7400g Plus lacks matrices, distribution functions, numerical integral, and polar graphing.

Casio is known as for their icon menus and the fx-7400g is no exception.  Here is the icon menu:

1:  Run
2:  Statistics
3:  List
4:  Graph
5:  Table
6:  Program
7:  Link
8:  Contrast
9:  Memory

For statistics, the fx-7400g offers the following regressions:  linear, med-med, quadratic, logarithmic, exponential, and power.

Curiosities of the fx-7400g Plus

Instead of the usual six function keys (F1 – F6), the fx-7400g Plus has four function keys, with two of them replaced with [ G<>T ] (graph-table switch) and [ > ] (next menu page).  I don’t know if the [G<>T] key is used today, but it is used two switch between the graph and home screen.  Today, the command only works when the current Casio graphing calculators (like the Prizm fx-CG 10) is in the Linear Input/Output mode. 

When a program is executed, the calculator is returned to the Run mode rather than stay in Program mode.  Exit program execution by pressing [AC/ON].

When Program Mode is entered, all the programs are listed chronically (when they first created).  There is no option to sort the programs alphabetically.

The fx-7400g handles calculations pretty quickly. 

Programming on the fx-7400g Plus

The programming command set on the fx-7400g Plus may be scaled down, but most of the commands we expect on the Casio Graphing calculators are present.  The lack of matrices, complex numbers, and a simplified list command set does provide a challenge, but we should be able to program for a lot of applications.

To get the quotes ( “ “ ), press [ALPHA] then [ F2 ].  This is the only way to get the quotation marks.

Programming Commands Available (not exhaustive):

[“prompt”]?  → var
   (right triangle)
:     (colon for multiple commands)

If Then [Else] IfEnd
Cond do if true: next
Do commands LpWhile cond
While cond commands WhileEnd
Dsz  var:  do if var ≠ 0: stmts  (-1)
Isz var:  do if var  ≠ 0stmts   (+1)
Goto,  Lbl

Break   (break from loops)
Prog “filename” (subroutines)

Fortunately any of the programs created on the fx-7400g Plus can be translated literally to later Casio graphing calculators. 

I will present programs on next blog entry.

Final Verdict

The fx-7400g Plus is not a bad entry-level calculator.  The early version is more an old-school graphing calculator. 

The updated fx-7400gII Casio now includes integral, polar graphing, base calculations, and complex numbers.  ( Link: )

Happy Thanksgiving!


This blog is property of Edward Shore, 2016.

No comments:

Post a Comment

HP 42S/DM 42/Free42: Function Table

HP 42S/DM 42/Free42: Function Table Introduction The program FTAB uses the function defined in FX, with variable “X” to gene...