Canon F-700

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"×½" Display size: 10+2 digits
Weight: 3 oz    
    Entry method: Algebraic with precedence 
Batteries: 1×"CR-2025" Lithium Advanced functions: Trig Exp Hyp Lreg Cplx Cmem BaseN Units Const 
External power:   Memory functions: +/-/×/÷ 
I/O:      
    Programming model: Partially merged keystroke 
Precision: 11 digits Program functions: Cond  
Memories: 7 numbers Program display:  
Program memory: 64 program steps Program editing:  
Chipset: NEC D75308GF   Forensic result: 9.0000389918  

f-700.jpg (21926 bytes)The F-700 is an interesting programmable calculator from Canon. Its programming model shares many features with that of other Canons. Curiously, its chipset may be different. Most Canon programmables that I've seen use Toshiba chips, but this one probably doesn't. I've not been able to open this F-700 to check, but I have an OEM calculator that appears to be an identical model: opening that Westfalia-Technik 269878 reveals a NEC chip. It stands to reason that the same chip is used in the Canon F-700. On the other hand, the Westfalia-Technik's circuit board reveals another label: Truly 105, which is a Hong Kong manufacturer. To top it all off, the machine's programming model is identical to that of many Casio calculators, and different from the programming model used in other Canons... Curiouser and curiouser!

64 partially merged program steps should be enough to write some decent programs, were it not for the fact that the programming model of this machine is very idiosyncratic indeed. It is similar to that of many Casio models in that very limited branching capability is offered: only two conditional instructions, the effect of both, if the condition is true, is that the program resumes execution at the beginning of program memory.

Even with this limitation, however, there's room for moderately complex algorithms. One example is the Gamma function; the program below computes its logarithm to 8+ digits of accuracy using Stirling's approximation and an iterative loop for small or negative arguments:

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
-
3
6
0
1/x
÷
MR
/
MR
x²
+
1
2
6
0
1/x
÷
MR
x²
x²
/
MR
-
0
x-K 1
=