Casio FX-602P

Datasheet legend
Ab/c: Fractions calculation
AC: Alternating current
BaseN: Number base calculations
Card: Magnetic card storage
Cmem: Continuous memory
Cond: Conditional execution
Const: Scientific constants
Cplx: Complex number arithmetic
DC: Direct current
Eqlib: Equation library
Exp: Exponential/logarithmic functions
Fin: Financial functions
Grph: Graphing capability
Hyp: Hyperbolic functions
Ind: Indirect addressing
Intg: Numerical integration
Jump: Unconditional jump (GOTO)
Lbl: Program labels
LCD: Liquid Crystal Display
LED: Light-Emitting Diode
Li-ion: Lithium-ion rechargeable battery
Lreg: Linear regression (2-variable statistics)
mA: Milliamperes of current
Mtrx: Matrix support
NiCd: Nickel-Cadmium rechargeable battery
NiMH: Nickel-metal-hydrite rechargeable battery
Prnt: Printer
RTC: Real-time clock
Sdev: Standard deviation (1-variable statistics)
Solv: Equation solver
Subr: Subroutine call capability
Symb: Symbolic computing
Tape: Magnetic tape storage
Trig: Trigonometric functions
Units: Unit conversions
VAC: Volts AC
VDC: Volts DC
Years of production: 1981  Display type: Alphanumeric display  
New price:   Display color: Black  
    Display technology: Liquid crystal display 
Size: 6"×3"×½" Display size: 10+2 characters
Weight: 5 oz    
    Entry method: Algebraic with precedence 
Batteries: 2×"CR-2032" Lithium Advanced functions: Trig Exp Hyp Sdev Cmem 
External power:   Memory functions: +/- 
I/O: Casio I/O     
    Programming model: Fully-merged keystroke entry 
Precision: 11 digits Program functions: Jump Cond Subr Lbl Ind  
Memories: 80(20) numbers Program display: Mnemonic display  
Program memory: 512 program steps Program editing: Auto-insert program entry  
Chipset:   Forensic result:  

fx602p.jpg (25003 bytes)Despite the prodigious number of calculator models Casio produced over the years, few are inspiring. This early LCD model, the FX-602P, is, however, an exception. A very well designed machine with considerable memory capacity, the FX-602P has a good programming model, several program control instructions, even something that's an absolute rarity on Casio calculators: indirect memory access.

One thing that this machine curiously lacks is display contrast control. (Unless there's some obscure key combination for it, described in a manual I do not have.) It took some time until I found an internal potentiometer that helped me turn down the display contrast; initially, the display was so dark, it was nearly unreadable.

Needless to say, as soon as I had a readable display, I began playing with my new calculator; and my playing, as usual, included writing another program for the Gamma function. This 82-step program neatly demonstrates the calculator's programming model, as it calculates the natural logarithm of the Gamma function for all real arguments to 10+ digits of precision:

001	Min00
002	1
003	Min01
004	5
005	MinF
006	LBL1
007	MR00
008	x>=F
009	GOTO2
010	MR00
011	×
012	MR01
013	=
014	Min01
015	1
016	M+00
017	GOTO1
018	LBL2
019	MR00
020	×
021	ln
022	-
023	MR00
024	+
025	(
026	2
027	×
028	π
029	÷
030	MR00
031	)
032	√
033	ln
034	+
035	(
036	(
037	(
038	(
039	9
040	9
041	1/x
042	÷
043	MR00
044	x2
045	-
046	1
047	4
048	0
049	1/x
050	)
051	÷
052	MR00
053	x2
054	+
055	1
056	0
057	5
058	1/x
059	)
060	÷
061	MR00
062	x2
063	-
064	3
065	0
066	1/x
067	)
068	÷
069	MR00
070	x2
071	+
072	1
073	)
074	÷
075	1
076	2
077	÷
078	MR00
079	-
080	MR01
081	ln
082	=