Sharp PC-1300S

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: 1979-1979 Display type: Alphanumeric display  
New price:   Display color: Green  
    Display technology: Vacuum fluorescent display 
Size: 9"×5"×1½" Display size: 16 characters
Weight: 1.5 lbs    
    Entry method: Formula entry 
Batteries: 4×"AA" NiCd Advanced functions: Trig Exp Prnt Snd Card 
External power: 8.2 VDC   Memory functions:  
    Programming model: mini-FORTRAN 
Precision: 12 digits Program functions: Jump Cond Subr Lbl Ind  
Memories: 42 numbers Program display: Text display  
Program memory: 640 program steps Program editing: Text editor  
Chipset:   Forensic result: 8.989923567  

Sharp PC-1300SLook what just arrived, straight from Tokyo: a true rarity, a first-generation magnetic card programmable calculator from Sharp, the PC-1300S. It is rare these days that I can hold in my hand a machine that is so completely different from other machines in my collection; the PC-1300S is truly unique, one of only a small handful of models that used magnetic cards for recording programs.

According to Yoshisuke Tsuji, who sent me this wonderful device from Japan (thank you!), the PC-1300S was less successful than it could have been; at the time, as part of a government-initiated effort to reduce Japan's tremendous trade surplus with the United States, many products were imported, including Hewlett-Packard calculators like the HP-67 and the HP-97, and the PC-1300S had to compete against those in the domestic marketplace.

The PC-1300S is called a "pocket computer", though you need rather roomy coat pockets to carry this machine about; nevertheless, it is a true portable, capable of operating from its built-in rechargeable battery.

It is described as programmable in "mini-FORTRAN", which is really just keystroke programming with some program control statements that were obviously inspired by the FORTRAN language. Loops are entered using DO and CNT (for continue); even the raise-to-the-power function is denoted using the double star, **, in true FORTRAN tradition.

Programs are shown in the machine's 16-character alphanumeric VFD display. The display is not very bright (I had to edit the scanned image on the right to increase the display contrast, and even so, the numbers are not very legible there) but it's still quite comfortable to use in normal office lighting conditions. Programs are shown symbolically (no cryptic keycodes here) and organized into lines; program labels are also available for easy keyboard access to subroutines. And, like its counterparts from Texas Instruments and Hewlett Packard, the Sharp PC-1300S also offers a slot over the display where a program card can be stored; any writing on the card appears here, identifying the functions of the A, B, C, X, and Y keys.

Programs can be listed using the built-in spark printer. The printer uses a lot of current; a fully charged battery is essential, otherwise any attempt to operate the printer just shuts down the calculator, even if it is connected to its wall charger. (This is not uncommon behavior; I've seen this in many other calculators, the current drawn by the printer exceeding the rated power of the adapter.)

Naturally, I could not resist playing with my 30-year old "new" machine. It has been quite a while since I last wrote a Gamma function test program for a completely new architecture! It's not very refined (I really ought to get back to work right now, as I have plenty on my "TO DO" list), but it works... Best of all, the calculator can record it flawlessly onto its hard plastic magnetic cards:

00; "A"
01; 1=>X
02; IF Z>5,GTO 6
03; X*Z=>X
04; Z+1=>Z
05; GTO 2
06; Z*LN Z-Z+LN (2*π/Z)/2+((((1/99/Z/Z-1/140)/Z/Z+1/105)/Z/Z-1/30)/Z/Z+1)/Z/12-LN X
07; END

Speaking of magnetic cards, it is curious that while American manufacturers, namely Hewlett Packard and Texas Instruments, opted to use a complicated, elaborate, motorized mechanism for card transport, both Sharp and Casio chose muscle power instead: the (hard) cards are slid through the reader slot by hand, not unlike the way credit cards are used today. Hewlett-Packard later adopted a similar mechanism for its HP-71B and HP-75C/HP-75D machines before abandoning magnetic card technology in calculators altogether.