I recently purchased two calculators from https://www.devicegoround.com:
* Casio fx115D SUPERFX and
* Radio Shack EC4004 (I'll talk about this in another post).
Date the fx115D SUPER FX was first manufactured: about 1995, according to calculator.org (http://www.calculator.org/pages/calculator.aspx?model=fx115D&make=Casio
I honestly thought this model was around in the late 1980s or early 1990s. Hard to tell when Casio does not date their user manuals.
As with most solarpowered calculators, the fx115D SUPER FX (herein referred to as fx115D from this point forward) has a battery backup. This means we can store data and it will be retained after the calculator is turned off.
In addition to the independent memory (M), the fx115D has six additional memory registers. The Kin key stores the number into one of the six registers, which the Kout key is the recall key. Better yet, the fx115D supports storage arithmetic.
Storage Arithmetic:
Let # represents registers 1 through 6:
Add x to #: x [ Kin ] [ + ] #
Subtract x from #: x [ Kin ] [  ] #
Multiply x to #: x [ Kin ] [ × ] #
Divide #/x: x [ Kin ] [ ÷ ] #
Constant arithmetic operation keys are executed by pressing the arithmetic key twice. Then enter each operand then the equals key. I wonder if anyone used this feature? Here are the procedures for constant arithmetic operation:
Addititon: x + a, x + b, etc...
x [ + ] [ + ] a [ = ], b [ = ], repeat
Subtraction: a  x, b  x, etc...
x [  ] [  ] a [ = ], b [ = ], repeat
Multiplication: x * a, x * b, etc...
x [ × ] [ × ] a [ = ], b [ = ], repeat
Division: a/x, b/x, etc...
x [ ÷ ] [ ÷ ] a [ = ], b [ = ], repeat
Other features include:
* Complex Numbers. This is unique for the time as complex numbers were the imaginary parts were entered with a [ i ] key (actually Kin and Kout were deactivated in this mode) instead of the a and b keys. Available functions in complex numbers: arithmetic, 1/x, absolute value, and argument. Powers, logarithms, and trigonometric functions worked only on real numbers.
* Engineering Mode. The shift of the number keys allowed the user to enter an engineering prefix (nano, micro, etc...).
* Single Variable statistics
* Linear Regression
* Base Mode with conversion, with Boolean functions AND, NOT, OR, XOR, and XNOR. The [ 1/x ] acts like a negation key, but I am not sure it is 1's or 2's compliment. The manual doesn't state.
* Fractions, complete with mixed/proper fraction conversion. The decimal/fraction works to, if you initially enter a fraction.
* ENG and <ENG key. These represent a number in different ways:
ENG: decreases the exponent part by 10^3, multiplies the mantissa by 1000
<ENG: increases the exponent part by 10^3, divides the mantissa by 1000
Example: 23400 [ = ]
[ ENG ] (23.4 x 10^3)
[ ENG ] (23400 x 10^0)
[ ENG ] (23400000 x 10^3)
23400 [ = ]
[ <ENG ] (0.0234 x 10^6)
[ <ENG ] (0.0000234 x 10^9)
[ <ENG ] (0.0000000234 x 10^12)
These keys are still present on Casio nongraphing calculators, including the entry level fx260 Solar.
The operating system is AOS (Algebraic Operating System). I realize that AOS is a Texas Instruments term, but it applies here. Simply put, any oneargument function (e^x, trig, log) are pressed after the number is entered. Example:
ln 2431.74 is calculated as 2431.74 [ ln ] (Result: 7.796362329)
Another calculator that I had fond memories of is now back in the collection.
Eddie
This blog is property of Edward Shore. 2014
A blog is that is all about mathematics and calculators, two of my passions in life.
Sunday, September 14, 2014
Retro: Casio fx115D SUPERFX
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Ha, what a coincidence! The fx115D was the first scientific calculator I ever got, and the fx115ES Plus is the one I'm using now.
ReplyDeleteBy the way, the fx115D certainly was around before 1995. I got mine in 1993, from Germany, so Calculator.org is off by at least 2 years.
Eddie, to be clear, you cannot enter:
ReplyDeletecos45 + isin45
into the fx115D calculator?
/Regards
Lonewolf(TM),
DeleteHere is one way to do it. First, enter Complex mode by pressing [MODE] [EXP]. Then:
45 [cos] [ + ] 45 [sin] [ x ] [Kin](i) [ = ]
Press [ > ] to switch between the real and imaginary part of the complex number.
Eddie
Amazing Eddie Shore! now I am going online to try and find one to buy (to replace my other oneline alwayscarry Casio fx260).
DeleteWere it not possible to input the trigonometric form of a complex number on the fx991D, I would have passed on buying one online. Thank you.
/Silicon Valley Regards
Ed, I need manual pdf for 115d
ReplyDeleteMine have blank pages
2,3,6,7,74,75,78,79
Mladen:
DeleteYou can try this page:
http://casio.ledudu.com/pockets.asp?type=654&lg=eng
I admit this is not the most detailed manual ever, it is only a quick guide.
Eddie
This comment has been removed by the author.
ReplyDeleteIs it worth grabbing one of these at Goodwill for $4?
ReplyDeleteYes! it's worth it. Change the battery as soon as you buy it.
ReplyDelete