Date of introduction:  November 1981 Display technology:  
New price:  $109.00 (MSRP 1981) Display size:  
Size:  3.2" x 6.2" x 1.75"
 82 x 158 x 44 mm3
Printer technology:  Electrostatic (Spark)
Weight:  9.8 ounces, 278 grams Serial No:  1B111A
Batteries:  4*AA Alkaline or NP-4M NiCd Date of manufacture:  mth 11 year 1981
AC-Adapter:  AD-4150 (4.5V DC, 500mA) Origin of manufacture:  Japan
Precision:   Integrated circuits:  CPU: HD43192A01
Program steps:   Courtesy of:  Joerg Woerner

Sharp Corporation introduced in June 1980 with the PC-1210 (and its sibling PC-1211) the World's first Pocket Computer with BASIC programmability. It took only about three months and Matsushita defined with their Panasonic HHC a new category of Hand-held Computers or Portable Computers. Main competitor in Japan, Casio Computer Co., Ltd, on the other hand introduced with the FX-501P and FX-502P in October 1979 their first keystroke Programmable Pocket Calculator with LC-Display, succeeded in March 1981 with the FX-601P and FX-602P, introducing a dot matrix LC-Display and laying the foundation for the FX-702P "Pocket Computer". Casio took a different approach than Sharp and added BASIC programmability to a Scientific Calculator and labeled the device with "Programmable Calculator" accordingly. Casio's early advertisement featuring the FX-702P used often a big headline "More Power To Your Pocket" to challenge rival Sharp.

The FX-702P Programmable Calculators features not only an internal expansion slot for a memory cartridge but a 7-pin connector for peripherals on its left side:

Product Description MSRP (1981)
FA-2 Cassette Interface
(Fits FX-501P/FX-502P/FX-601P/FX-602P, too)
FP-10 Mini Printer, electro-sensitive FP-36 paper, up to 20 characters per line, 2 lines per second
(Fits FX-601P/FX-602P, too)
(not released) 4k Bytes RAM module with backup battery  
(not released) 8k Bytes RAM module with backup battery  

Dismantling the featured Casio FP-10 manufactured in November 1981 by Casio Computers in Japan reveals a complex design based on two printed circuit boards (PCBs) in a clamshell packaging and powered by four AA-sized Alkaline batteries.

One of the PCBs holds the power electronics for the electrostatic printer while the other PCB provides the brain of the Mini Printer:

HD43192A01: 4-bit microcontroller with integrated RAM and ROM and printer driver for 8 electrodes manufactured
   by Hitachi in a CMOS process and using an 80-pin QFP (Quad Flat Pack) package

Consolidating the part numbers of the microcontrollers and display controllers, and printer controllers located in the FX-702P BASIC Programmable Calculator, the FX-602P keystroke Programmable Calculators, and the FP-10 Mini Printer, respectively proves their close relationship:

FX-602P: HD43190A01, HD43191A01
FX-702P: HD43190A02, D43190A03, HD43191A02, HD43191A03
FP-10: HD43192A01

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If you have additions to the above article please email:

Joerg Woerner, January 5, 2021. No reprints without written permission.