Canon F-73P

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: 5½"×3"×½" Display size: 10(8+2) digits
Weight: 4 oz    
    Entry method: Algebraic with precedence 
Batteries: 2×"LR44" button cell Advanced functions: Trig Exp Hyp Lreg Cmem BaseN Units 
External power:   Memory functions:
I/O:      
    Programming model: Partially merged keystroke 
Precision: 11 digits Program functions: Jump Cond  
Memories: 7 numbers Program display:  
Program memory: 45 program steps Program editing:  
Chipset: Toshiba   Forensic result: 9.0000278593  

f73p.jpg (27495 bytes)A slim, elegant, and useful model, the Canon F-73P is a nice example of a programmable scientific calculator. That despite the fact that its programming model is somewhat limited: 45 partially merged steps isn't a great deal of program memory, and the inability to edit/view programs is annoying.

That said, 45 partially merged steps can be quite useful, especially when the calculator does offer limited decision-making capabilities: in the case of the F-73P, the ability to execute conditional and unconditional jumps within the code. In fact, it is this what distinguishes a true computer from a mere automaton; I guess the F-73P would qualify as a device banned by the Great Convention in Frank Herbert's immortal Dune!

The chipset of the F-73P is used in other calculators. I first came across a similar model when my friend Joerg Woerner sent me a Citizen SR-59. At first, I found the programming model too limited, too constraining; eventually, however, I was able to squeeze even complex algorithms into this machine's memory, including the following iterative program for the incomplete Gamma function:

01:  STO
02:  2
03:  RM
04:  STO
05:  1
06:  ax
07:  RCL
08:  2
09:  ÷
10:  RCL
11:  1
12:  ex
13:  ÷
14:  RCL
15:  2
16:  =
17:  STO
18:  3
19:  SM
20:  RCL
21:  3
22:  ×
23:  RCL
24:  1
25:  ÷
26:  (
27:  GOTO 1
28:  GOTO -9
29:  RCL
30:  2
31:  +
32:  1
33:  )
34:  STO
35:  2
36:  GOTO 1
37:  GOTO -9
38:  +
39:  STO
40:  3
41:  RM
42:  =
43:  x<=M 1
44:  GOTO -7
45:  RM