Early Electronic Calculator Casio AL-1000 Calculator Technical Description

This article presents a detailed technical description of the Casio AL-1000 calculator. The contents of this article are based on a reverse engineering of one unit of this calculator, which I received in a dismantled and non-functional state (it was missing the case and power supply and the bundle of 50-or-so wires connecting the keyboard to the backplane had been chopped).

This article is an adjunct to the schematic produced from the reverse engineering. Some references and descriptions may not make much sense without reference to the schematic. A simulation of the AL-1000 has also been completed and can be used to observe the execution of the procedures described in this article.

The AL-1000 dates from the late 1960s. It provides the basic four arithmetic functions and square root. Simple straight-line programs of up to 30 steps can be stored and executed by the AL-1000. It utilises more than 400 discrete transistors, over 1500 diodes, Nixie tubes for the display, and core memory for number and program storage.

The AL-1000 was also sold under the Commodore label.

Other information about the AL-1000:

• EEC AL-1000 schematic.
• EEC AL-1000 page.
• EEC AL-1000 simulation.
• Pictures and other descriptions can be found on Rick Bensene's AL-1000 pages. (Thanks to Rick for providing the power supply voltages on his pages, as my unit was missing the power supply.)
• And on Nigel Tout's AL-1000 pages.