Ibico 098

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: Numeric display  
New price:   Display color: Black  
    Display technology: Liquid crystal display 
Size: 5"×3"×¼" Display size: 10(8+2) digits
Weight: 2 oz    
    Entry method: Algebraic with precedence 
Batteries: 2×"V389" button cell Advanced functions: Trig Exp Hyp Sdev Cmem 
External power:   Memory functions:
I/O:      
    Programming model: Partially merged keystroke 
Precision: 11 digits Program functions:  
Memories: 3 numbers Program display:  
Program memory: 40 program steps Program editing:  
Chipset: Sharp LI3301A   Forensic result: 9.0000156204  

ib098.jpg (22903 bytes)This Ibico 098 is yet another one of a line of calculators from many different manufacturers utilizing the Sharp LI3301A calculator circuit. I already have at least thirteen such machines in my possession, and I fully expect that there'll be more, models I don't know about yet, which use the same chip.

The programming model of this chipset is primitive, but its biggest drawback, in my opinion, is that questionable "feature" of zeroing out the X-register when a program is about to be entered. What this means, in effect, is that no algorithm that fails for an argument of zero can be entered. You wish to enter a program that computes the logarithm of a number? No such luck... the logarithm of 0 is undefined and causes an error condition, so your program will not be entered into memory.

Or perhaps the makers of this chipset assumed that all programs will be "prompting" programs, as opposed to operating on the contents of the display register?

Oh well. The limited programming model means no Gamma function on this machine. Here is, instead, an implementation of Stirling's formula:

MS
1
M+
÷
MR
÷
1
2
-
3
6
0
1/x
/
MR
/
MR
x2
+
1
=
×
MR
yx
MR
÷
MR
ex
×
(
2
×
π 
÷
MR
)
√ 
=