Ein Ausschnitt
Computermuseum der Fakultät Informatik                            German

Casio AS-A, AS-C, AS-L

casio AS-
Manufacturer: Casio                             <<<    ***    >>>    ^^^
Type:         AS-A, AS-C, AS-L
Technology:   PMOS
Year:         1970-1972
Price:        ~ DM 2000.-

These three desktop calculators show the progress in semiconductor
technology at the end of the 1960ies.
The very primitive AS-A, it has for example no decimal point key, is
built with two printed circuit boards with a total area of 153cm².
They contain 34 integrated circuits with mostly 14 or 16 pins.
The AS-C needs the same PCB-area, but by using higher integrated circuits
it is significantly more powerful. One can see 14 small ICs an four 36-
pin ICs made by Fairchild on the lower PCB.
The AS-L needs only a PCB-area of 84 cm² and has an architecture
which can be seen as a kind of microprocessor with the exception, that
the CPU is still not integrated on one single chip.
Its program memory consists of 2*256 words with 8 bits, from which all
except of one are really used. Data memory on all three calculators are
PMOS-shift registers, data processing is bit-serial.

AS-A and AS-C use older high-treshold-technology from Hitachi (HD 31..
with -24 volt supply), the AS-L uses a newer low-lhreshold-technology 
(HD 32.. with -14 volt).

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