Casio fx-8500G

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: 1989  Display type: Graphical display  
New price:   Display color: Black  
    Display technology: Liquid crystal display 
Size: 7"×3½"×½" Display size: 96×64 pixels
Weight: 8 oz    
    Entry method: Formula entry 
Batteries: 3×"CR-2032" Lithium Advanced functions: Trig Exp Hyp Lreg Grph Cmem BaseN 
External power:   Memory functions:  
I/O: Casio I/O     
    Programming model: Formula programming 
Precision: 12 digits Program functions: Jump Cond Subr Lbl Ind  
Memories: 6(0) kilobytes Program display: Formula display  
Program memory: 6 kilobytes Program editing: Formula entry  
Chipset:   Forensic result:  

fx8500g.jpg (62481 bytes)The fx-8500G is another calculator from Casio's fx-8000 family, shown here with the FA-80 cassette/printer interface.

The program below demonstrates the calculator's programming model by implementing the Gamma function using the solution from Numerical Recipes in C:

"X=":?->X
1->Y
Lbl 1
X>=0=>Goto 2
XY->Y:X+1->X
Goto 1
Lbl 2
e(ln ((1+(76.18009172+9.5E-9)÷(X+1)
  -86.50532033÷(X+2)+24.01409824÷(X+3)
  -1.231739572÷(X+4)+1.208650973E-3÷(X+5)
  -5.395239384E-6÷(X+6))×
  √(2π)÷X)+(X+.5)× ln (X+5.5)-X-5.5)÷Y