Casio fx-3800P

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/log 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: Li-ion rechargeable battery
Lreg: Linear regression (2-var. stats)
mA: Milliamperes of current
Mtrx: Matrix support
NiCd: Nickel-Cadmium recharg. batt.
NiMH: Nickel-metal-hydrite rech. batt.
Prnt: Printer
RTC: Real-time clock
Sdev: Standard deviation (1-var. stats)
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: 1986  Display type: Numeric display  
New price:   Display color: Black  
    Display technology: Liquid crystal display 
Size: 5½"×3"×½" Display size: 10+2 digits
Weight: 4 oz    
    Entry method: Algebraic with precedence 
Batteries: 1×"CR-2025" Lithium Advanced functions: Trig Exp Hyp Lreg Cmem BaseN 
External power:   Memory functions: +/-/×/÷ 
I/O:      
    Programming model: Fully-merged keystroke entry 
Precision: 11 digits Program functions: Cond  
Memories: 7 numbers Program display:  
Program memory: 135 program steps Program editing:  
Chipset:   Forensic result: 9.0000157179  

Casio fx-3800P

fx3800p.jpg (21972 bytes)With its 135 fully merged program step capacity, the fx-3800P could be a respectable high-end programmable calculator. Unfortunately, its generous program capacity is not accompanied by a sophisticated programming model; all that's in there is a simple branch capability, that allows jumping to the beginning of program space only. Worse yet, you cannot edit or view programs; all 135 steps must be entered "in the blind", and if you made a mistake, you can start from the beginning.

I first encountered this calculator in its OEM guise as the Radio Shack/Tandy EC-4019. It is on the EC-4019 that I developed the following programming example, which computes the Gamma function for positive arguments: 

K1=76.18009173
K2=86.50532033
K3=24.01409824
K4=1.231739572
K5=1.208650974E-3
K6=5.395239385E-6


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