Post Reply 
CASIO fx-5500 Scientific Calculator: The 1st "C.A.S." pocket calculator?
02-22-2017, 11:33 PM (This post was last modified: 02-22-2017 11:55 PM by jebem.)
Post: #1
CASIO fx-5500 Scientific Calculator: The 1st "C.A.S." pocket calculator?
"Factoring made easy" by Casio in 1986!

Was this CASIO fx-5500 the first calculator in the market able to do symbolic calculus (formula manipulation) although in a very limited format, otherwise known as C.A.S. these days?

This machine belongs to another local collector that kindly allowed me to have for some time for testing.

[Image: Casio_fx-5500_002.jpg]


This is a handy little machine, almost of the same size and form as the HP Voyager series, although featuring totally different capabilities and operation philosophy.

[Image: Casio_fx-5500_000.jpg]


Main features, based on the user manual:
  • 24 digit LCD with 5x7 dot matrix alphanumeric capability.
  • Analog contrast adjustment.
  • Constant Memory.
  • Power supply: 2xCR2032
  • True algebraic logic operation. Replay for easy editing
  • Display: 10 digits mantissa and 2 digits exponent.
  • Internal: 12 digits mantissa and 2 digits exponent.
  • Each result is rounded to 10 digits for display
  • Stack sizes:
    - Manual operations: Numeric 8 levels, command 20 levels.
    - Formula manipulation: Numeric 15 levels, command 20 levels.
  • Input buffer size for each entry: 79 steps storage area for numbers and commands
  • Memories:
    - 3 x Formula memories (I, II, III). Each up to 79 steps.
    - 12 x Register memories (A to L)
  • 34 functions
  • Symbolic calculus (Formula manipulation):
    - Expansion
    - Factoring
    - Simplify
  • Solver (one unknown quadratic and linear, three unknown linear)

Forensics test: arcsin (arccos (arctan (tan (cos (sin (9) ) ) ) ) )
Result: 9.000007164 the same as for the Casio fx-730P among others.
Doing (9-Ans) *1000000 to find additional internal digits gives just 7.164.

[Image: Casio_fx-5500_003.jpg] [Image: Casio_fx-5500_004.jpg]


Using some expressions from the user manual examples to test the symbolic manipulation capability.
Well, it is not a powerful manipulation and we can't even consider it a full C.A.S. system, but in 1986 it was something rare, if not unique, to see on a pocket calculator.

Simplify 5X^2 + 7X - 6 - 3X^2 + 2X + 9

Took about 2 seconds to find this result: 2X^2 +9X + 3

[Image: Casio_fx-5500_009.jpg] [Image: Casio_fx-5500_010.jpg]


Just for fun, tried to Expand (X + 3)^5
It took about 8 seconds to find this result: X^5 + 15X^4 + 90X^3 + 270X^2 + 405X + 243

[Image: Casio_fx-5500_011.jpg] [Image: Casio_fx-5500_012.jpg] [Image: Casio_fx-5500_013.jpg]

Jose Mesquita
RadioMuseum.org member

Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
CASIO fx-5500 Scientific Calculator: The 1st "C.A.S." pocket calculator? - jebem - 02-22-2017 11:33 PM



User(s) browsing this thread: 1 Guest(s)