+Home     Museum     Wanted     Advertising     Articles     EMail  

Advertising & Documentation Archive

Sharp CSA-12 "Memorizer 60" Programmer Manual

Front cover of Sharp Memorizer 60 (Model CSA-12) Automatic "Programer" Operating Instructions

The Model CSA-12, called the "Memorizer 60", along with its half-capacity Memorizer 30, were accessory devices that could be connected to certain models of Sharp electronic calculators to provide a rudimentary learn-mode programming capability.

The Memorizer 30 and Memorizer 60 were announced by Hayakawa Electric in September of 1968, and were on the market beginning first in Japan in late 1968, and in North America by early 1969.

The early examples of the Memorizer 30/Memorizer 60 could be connected to a special socket on the back panel of the Sharp Compet 22 or Sharp Compet 32 calculator. A revised version (denoted with a B at the end of the serial number) was released sometime in mid-1969 that allowed connection to two additional calculators, the Sharp Compet 33 (same as the Compet 32, but omits the Square Root function), and the new Sharp Compet 50, Sharp's first printing electronic calculator.

With a Memorizer connected to one of these calculators, the device would allow a sequences of key presses of up to 30(Memorizer 30) or 60(Memorizer 60) steps in length to be stored within a magnetic core memory array located within the Memorizer device. Once a sequence of key presses was stored, the sequence could be "played back" to the calculator, which would carry out the functions of the key presses as if they had been entered on the calculator keyboard, albeit in a much faster fashion than a human could enter them. A special code could be stored in the memory of the Memorizer using a key on the front panel of the memorizer that would halt the sequence of steps to allow the operator to enter values for variables on the calculator keyboard, as well as to indicate the end of a program. The Memorizer devices only allowed linear sequences of keyboard keys to be entered, e.g., there was no direct capability to perform looping or conditional tests as would be provided by a true programmable calculator. It was possible to manually implement loops by utilizing the ability of the Memorizers to break the step storage space into two separate spaces of 15(Memorizer 30) or 30(Memorizer 60) steps. A switch on the panel of the Memorizer selects which program space to be used when entering or playing back key press sequences. By putting all of the initialization and initial data entry steps into Program I, then switching to Program II, and performing the steps involved in the iterative part of a calculation, Program I could be run first in order to set up for the looping operation, then the operator would switch to Program II, and repeatedly execute the iterative part of the sequence (perhaps with additional stops for data entry) for a specified number of times, or until a result converged such that changes in the answer were no longer occurring.

These devices were a stop-gap measure for Sharp, as it was not long before similar functionality with improved capabilities were integrated into some models of Sharp's calculators, no longer requiring an external device to provide programmability. For this reason, the market lifetime of the Memorizer devices was fairly limited, and although an exact date when production on the devices halted, it is expected that by the early part of 1971, the devices were no longer being produced. Because of the limited market lifetimes of the calculators that the Memorizers would work with, as well as lower-cost calculators with basic built-in programming capabilities were available not long after the Memorizers were introduced, not many of these devices appear to have been manufactured, making them quite uncommon today.

The Old Calculator Museum has a Memorizer 60 in its collection that requires some restoration work (a broken conductor in the cable that connects the Memorizer to the calculator), as well as requiring a full check-out before connecting to a calculator, but when it (hopefully) is restored to full operation, it will certainly be exhibited here, likely with a video demonstration of it in operation.

Note the misspelling of "Programer"(sic) on the cover of the manual.

Scanning of the manual for the Memorizer 60 is on the To-Do list for the museum, and will be posted once it is available.