**Retro Review: Sharp EL-9600c**

I
wanted to buy this calculator when the EL-9600c first came out during the late
1990s. 20 years later, I am finally
getting my hands on it.

**Essentials**

Company: Sharp

Years: 1990s (I think it is late 90s)

Type: Graphing, Programming

Memory: 24,000 (about 20,000 available RAM)

Operating
System: AOS (post-script)

Memory
Registers: 27 (A-Z, θ)

Screen: Monochrome

Batteries: 4 AAAs with CR2032 backup

Graphing
Modes: Function (10), Polar (6),
Parametric (6), Sequence (3)

Finance: Time Value of Money Solver, NPV, IRR, days
between dates (1950 to 2049 only)

Regressions: 14:
Med-Med, Linear (ax+b, a+bx), Logarithmic (a + log x, a + ln x), Power,
Exponential, Inverse, Logistic, Sinusoidal, Polynomial (quadratic, cubic,
quartic)

Solvers: General (Newton’s method), Polynomial (2, 3),
Simultaneous Equations (2 to 6 variables)

Matrices: Up to
10 (no eigenvalues, darn it! Oh well.)

Complex
Numbers: Rectangular and Polar
coordinates. Arithmetic, logarithmic,
power, exponential,

*but not trigonometric*
By default,
expressions are entered in natural print format, though you can change it to a
linear input format. There is no
automatic conversion to fractions nor does simple fractions involving π or simplifying
square roots leaving answers with square roots are present. Everything calculated is in decimal.

One glance at
the EL-9600c and one could tell that this is similar to the 1990s TI-83 Plus/monochrome
TI-84 Plus and you’d be almost right.

**Keyboard**

The keys are
rubber keys which will require a firm touch.
A light touch will not register the key press. You will need to pay attention to the screen
to see if the key has registered. It is
not terrible, but there is room for improvement. Honestly, as someone who likes to type fast,
it gets annoying because I find myself having to backtrack a lot.

What is also
weird is that the [ON] key is recessed.

**Integration**

An oddity: it takes TWO commands to integrate. The first is the integration command itself (∫,
MATH – CALC - 05) but you will need to add the dx at the end (MATH – CALC – 06).

**Unique Functions of the EL-9600c**

**One-Screen Base Conversions**

In
the TOOL menu, you can access a screen where you can convert integers between
four bases: binary, decimal, octal, and hexadecimal. The integers are 15 bits, with the front bit
used as the sign bit (1 for negative, 0 for positive).

For
binary, the upper limit is 0111111111111111, or 32767 in decimal, 77777 in
octal, and 7FFF in hexadecimal.

**Rapid Graph (the EZ button)**

The
EZ graphing function command offers up to 51 graphing templates to copy to a
graphing variable. Examples include:

Y
= AX^2 + BX + C

Y
= A√(BX)

Y
= A sin(BX + K)

Y
= A/X

Y
= A log(X – H)+K

Pressing
[2ndF] [WINDOW] (SUB) allows the user to enter values for the variables A – Z (except
X, R, T, Y, for obvious reasons). To see
the graph full screen, press [GRAPH].

The
Rapid Graph function doesn’t stop there.

Pressing
the [EZ] button in the Graph screen presents the graph screen surrounded by
up/down, right/left buttons that adjust the Xmin, Xmax, Ymin, and Ymax
values. I recommend that you use the
included stylus pen included with this screen.
(more on the pen later)

If
you press the [EZ] button on the Window screen, you are presented with lots of
quick setting options, centered around which quadrants (I, II, III, or IV) you
want to emphasize. Pressing [ENTER] presents you with parameter options.

**Pen**

The
EL-9600c includes a pen stylus which is stored on the bottom right slot of the
calculator. The pen serves several
purposes:

*
Allows for quick selection and scrolling of function menus.

*
Choosing a new location of the cursor in a graphing screen. If you are in tracing mode, the cursor
follows the selected function.

*
On the main screen (access by pressing the [+ - * ÷] button), you can select
the last (only the most recent) calculation for editing. You can also place the cursor where you want
during editing.

Overall
the pen is nice, but it seems like should the pen be lost, the functionality of
the EL-9600c is not lost.

**Slide Show**

You
can create slide shows on the EL-9600c.
The calculator comes with eight built-in slide shows. Creating slide
shows is pretty easy. After naming your
slide show, you get access to the full calculator. For every screen you want to copy, just press
[2ndF] [SLIDE SHOW] (CLIP). The screen
is copied. Slide shows can be edited and
individual slides can be deleted.

I
created a six slide show, and it takes about 1875 bytes.

**Programming**

The
programming on the EL-9600c is pretty basic.
I’m not kidding. There are no
structures such as IF-THEN-ELSE or FOR-NEXT.
Yes there is an If command, but it is

*extremely limited*! The only command that can follow the If is a Goto command.
For
the EL-9600c, label names can be up to 10 characters. A program can contain up to 50 labels. I believe that labels are local.

There
are subroutines by the use of the Gosub and Return commands.

The
input and output commands are barebones as well, we just have Print and
Input. However, you can use the Wait
command to control output.

Access
to graphs and tables are available in the programming language.

**Sample Program: Digital Root**

EL-5600c
Program DROOT

Rem
EWS 2017-07-08

Print
“N

Input
N

If
N≤0 Goto INVALID

N –
9 * iPart ((N-1)/9) ⇒ D

Print
D

End

Label
INVALID

Print
“INVALID ENTRY

Example: N = 13467, Result: D = 3

**Final Verdict**

The
Sharp EL-9600c is a feature rich calculator.
The biggest selling point for me was the [EZ] (Rapid Graph) button which
allows the user to quickly enter from 51 templates. I also like the easy to use Slide Show
feature. If only the EL-9600c was still
produced and had a USB connection the slide shows that would be presented.

My
biggest complaint is the keyboard, because I can’t type pretty fast. Also, I find the programming language is
pretty limited for a graphing calculator (which supposedly to be above the
TI-81). I do plan to do several programs
for the EL-9600c in the future.

It
is a nice calculator to add to the collection as always, even it is two decades
later for this particular calculator.

Eddie

P.S.
Coming soon: a retro review on the
Hewlett Packard HP 22S.

This
blog is property of Edward Shore, 2017