Texas Instruments TI-80

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:   Display type: Graphical display  
New price:   Display color: Black  
    Display technology: Liquid crystal display 
Size: 6½"×3"×½" Display size: 64×48 pixels
Weight: 5 oz    
    Entry method: Formula entry 
Batteries: 2×"CR-2016" Lithium Advanced functions: Trig Exp Hyp Lreg Grph Cmem Mtrx BaseN 
External power:   Memory functions:  
I/O:      
    Programming model: Formula programming 
Precision: 13 digits Program functions: Jump Cond Subr Lbl Ind  
Memories: 7(0) kilobytes Program display: Formula display  
Program memory: 7 kilobytes Program editing: Formula entry  
Chipset:   Forensic result:  

ti80.jpg (24595 bytes)Under ConstructionThe TI-80.

 

Here is what a program that calculates the Gamma function for any real argument looks like on the TI-80:

:INPUT X
:1->Y
:LBL 1
:IF X>=0
:GOTO 2
:XY->Y
:X+1->X
:GOTO 1
:LBL 2
:e^(LN ((1+76.18009172947/(X+1)
  -86.50532032942/(X+2)+24.01409824083/(X+3)
  -1.23173957245/(X+4)+1.208650973866E-3/(X+5)
  -5.395239384953E-6/(X+6))√(2π)/X)
  +(X+.5)LN (X+5.5)-X-5.5)/Y->Y
:DISP Y