Privileg PR-57NC
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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Privileg PR-57NC
The Privileg PR-57NC is yet another European OEM copy of the classic Commodore PR-100: my first ever programmable calculator, the PTK-1072, was an identical machine, except that it was sold under a Hungarian OEM label.
A do-everything machine, the PR-57NC's main limitation is a completely unmerged programming model: every keystroke, including the F key and the (inv) key counts as separate keystrokes. This makes the calculator's 72-step program space more limited than necessary.
Back in the late 1970s, I found it a challenge to create an algorithm for this calculator that would compute the Gamma function. Today, I have several; one I developed just recently, based on an excellent suggestion I received from Robert H. Windschitl. With his empirical formula, it became possible to compute the Gamma function's logarithm to 8+ digits of precision, squeeze the algorithm, along with an iterative loop for small or negative arguments, into the PR-57NC's memory, and have some room to spare (specifically: 7 unused program steps.) My only wish now: a time machine with which I could send this result back to my younger self for his enjoyment (along with last week's lottery numbers of course.)
00 51 M
01 81 1
02 85 -
03 72 5
04 84 +
05 15 SKIP
06 14 GOTO
07 81 1
08 61 7
09 73 6
10 95 =
11 21 F
12 74 M×
13 81 1
14 14 GOTO
15 91 0
16 82 2
17 72 5
18 74 ×
19 51 M
20 91 0
21 21 F
22 35 1/x
23 21 F
24 22 sinh
25 84 +
26 64 (
27 52 MR
28 91 0
29 34 yx
30 73 6
31 94 +/-
32 75 ÷
33 62 8
34 81 1
35 91 0
36 95 =
37 35 √
38 74 ×
39 52 MR
40 91 0
41 95 =
42 32 ln
43 74 ×
44 52 MR
45 91 0
46 85 -
47 52 MR
48 91 0
49 84 +
50 64 (
51 82 2
52 74 ×
53 45 π
54 74 ×
55 52 MR
56 91 0
57 65 )
58 35 √
59 32 ln
60 85 -
61 52 MR
62 81 1
63 32 ln
64 95 =