Casio fx-3600Pv
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 |
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An interesting modern variant of Casio's venerable low-end programmable scientific calculator series, the fx-3600Pv also happens to be a machine with a curious bug, a bug not present in its predecessor, the fx-3600P. I encountered this as I was trying to create a program to compute the Gamma function, which of course is my favorite programming example for calculators. Take a look at this simple program:
+
ln
Kin+1
1
=
x<=M
0
x-K 1
This program should compute the logarithm of the products of numbers starting from the number in the display, up to and including the number in the calculator's independent memory. For instance, if the number on the display is 5, and the number in memory is 9, running this program should produce 9.62377..., i.e., the natural logarithm of 15120 (=5×6×7×8×9). What it does compute instead is something completely different: 13.57639..., which is the logarithm of 787320. It took me some time to figure out this riddle: 787320=9×18×27×36×5! I.e., while we're decrementing the single-digit argument in the display register, a phantom digit in the second position appears in the multiplication. The same effect is not reproduced if you perform this calculation by hand; nor is this effect present if the independent memory contains a number greater than, or equal to, 10.
Oh well, scratch one useful method for shortening my Gamma function program. Here is a program anyway, one that performs a somewhat lengthier calculation but avoids this bug.
Kin 2 ln Kin+ 1 9 Min Kout 2 + 1 = x<=M X Min ln - MR + ( 2 * π / MR ) √ ln + 1 2 1/x / MR - 0 x-K 1 =