Casio PB-500

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:   Display type: Alphanumeric display  
New price:   Display color: Black  
    Display technology: Liquid crystal display 
Size: 3½"×7½"×½" Display size: 24 characters
Weight: 8 oz    
    Entry method: BASIC expressions 
Batteries: 2×"CR-2032" Lithium Advanced functions: Trig Exp Cmem Snd 
External power:   Memory functions:  
I/O: Casio I/O     
    Programming model: BASIC 
Precision: 12 digits Program functions: Jump Cond Subr Lbl Ind  
Memories: 2(0) kilobytes Program display: Text display  
Program memory: 2 kilobytes Program editing: Text editor  
Chipset:   Forensic result: 9.00000716758  

Casio PB-500

pb500.jpg (46537 bytes)Like its larger cousin, the PB-700, this Casio calculator managed to trick me: for a while, I didn't understand why my attempts to enter any command resulted in a display of SN error. Then I remembered: its two ENTER keys are not identical in functionality. The ENTER key on the numeric keypad is used to input calculator expressions for immediate evaluation; the ENTER key in the QWERTY keypad is used to enter BASIC expressions and program lines. A neat way to avoid the dreaded MODE switch I guess, but it can be a bit annoying when you don't remember this "feature"!

The PB-500 is a classic style Casio BASIC pocket computer released only in the Japanese market. Its 2.8 kB main memory can be supplemented by up to two RAM cards. These cards can also be used in other Casio computers, including another Japan-only model I recently came across, the runtime-only MMC.

The PB-500's programming model is similar to that of other Casio BASIC calculators, as demonstrated here by my favorite example, the Gamma function: 

10 INPUT X
20 G=1
30 IF X>5 THEN 70
40 G=G*X
50 X=X+1
60 GOTO 30
70 G=X*LOGX-X+LOG(SQR(2*PI/X)/G)
80 G=G+((((1/99/X/X-1/140)/X/X+1/105)/X/X-1/30)/X/X+1)/12/X
90 PRINT G,EXPG