1977 · Programmable Calculator with Modules · Work 952 of 1,871
A land surveyor's office in Texas on a hot afternoon, on a drafting table a long wedge-shaped black calculator resting in a wide low black printer cradle, at its upper end a narrow dark red display window with a faint red glow, a dark brown key field framed by a thin gold line, rows of dark brown, cream-white and pale orange keys, every key plain, smooth and unmarked, a short blank strip of white paper curling from the cradle, a hand in a plaid flannel sleeve holding a small black plug-in module between two fingers, a brass theodolite on a wooden tripod in the corner, slatted sunlight.
What it was used for
The TI-59 programmable calculator appeared in 1977; the New York Times gave a list price of 299.95 dollars in May 1977, it was offered at 219.95 dollars in December 1977 and at 169.95 dollars in November 1982. It holds 960 program steps and 100 memories, calculates internally to 13 digits and shows 10 of them on a red LED display. Besides the keyboard, programs reached the machine by 2 routes: magnetic cards through a slot on the right-hand side, and solid-state modules in the compartment on the back, the Smithsonian's example coming with the Master Library and Leisure Library modules. Attached to the PC-100 printer, it could print arbitrary text.
What was new
What marked the TI-59 was the second input route. Beside the magnetic card the user wrote himself there was a pluggable read-only module holding a finished program package - software thus became an object on a shelf and not only a recording. To that comes the sheer size of the store: 960 steps and 100 registers in a device of 6½ x 3 x 1½ inches and 12 ounces. The barb lies in the durability of the two media. rskey reports that cards were still readable after nearly 20 years while the reader's rubber pinch roller decays: the recording held up better than the part that had to read it.
What the sources leave open: Prices, modules and equipment come from the Smithsonian object page; 960 steps, 100 memories, 13-digit accuracy, dimensions and the pinch-roller note from rskey.org. The Smithsonian page gives no step or register count, rskey no new price. Neither source says anything about how the store was partitioned between program and data.