About older Casio Calculators
to the article
OLD CASIO CALCULATORS
please find a couple of line drawings covering the 'Older
Casio' models. The author does not have illustrations of
these models only Schematics and line drawings. The
information is posted so that people intereseted in the
subject can evaluate the information and see if it may be
of future beneficial use to the 'calculators collective'.
Early desktop Casio calculator model 121-161. Uses
discrete transistor logic consisting of a a row of
flip-flops. The data cycles through an adder. A nixie
tube type display is clocked to display the data relying
on residual intensity to keep the display visable to the
next cycle. Has no memory, as such, the flip-flops hold
the data. Typical of the period (Circa June 1969).
Casio CM-603 ON THE LEFT Circa Apr 1973. Portable. Also sold as the Remington 663. Battery operated (giving about six hours on four UM-3 Batteries, or AC operated, this calculator uses the traditional discrete seven segment display plus a decimal point (the tube operating like an anode valve with a heater filament). The microPD LSI (µPD usually indicates it was made by NEC) drives the segments of the display fromn S1 through S8 Digits 1 through 6 were also driven by the CPU through an inverter IC T3144 (Toshiba ?).
|The Mini Delux
Illustrated below was a generic D-73D-X001 later renamed
the DX-73D was a smallish calculator for the period.
Battery Operated (4 X UM3) it could also be mains driven
through an A/C adaptor. The Display was a LD8105 which I
refer to as a Flouro display. Basically this means the
display was encapsulated in one complete glass envelope
containg a filament. The wires to connect the Digital
anodes and the segment wires came out of the end of the
envelope for soldering to the PCB. One had to make
certain one got it right the first time as once the leads
were cut you were committed to the process. Using an LSI
(µ970C the machine was clocked by a T3184 IC pulse
generator. It was a very capable calculator as it had a
left shift key to recall data off the machine it also had
Total and Percentage Keys.
The R3 was an early printing Calculator that superseded the R1 (April 1971) and R2 (which was released later at an unknown date), the R3 being released in June 1972. It was an LSI operated calculator. Processor CPU's were HD 32101P : HD 32103P : HD 3213P and Memory Chips HN3255P & HN3207P (origin unknown) HD Usually indicated Hitachi. It used quite a lot of discrete IC gates and the data was clocked through memory registers and an adder. Considering the year the machine could be classified as advanced for the time. It was mains operated. The display was a flouro type display drive by two separate LSI's also HD (Hitachi sourced chips). The printer mechanism was driven by buffering chips HD3219P. The generic number was A12L-2.E2 which was a departure for the usual AX number although it was also listed as a DX29.
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Copyright © January 1998 Ray Mackay All rights reserved ® 1998
Updated June 21, 2004