TI-59 / TI-58

TI-59
A TI-59 showing a magnetic storage card being inserted into the card reader in the side
TypeProgrammable
ManufacturerTexas Instruments
IntroducedMay 1977
Discontinued1983
CostUS$300
Calculator
Entry modeInfix
Precision13
Display typeLight-emitting diode
Display size10 digits
CPU
ProcessorTMC0501
Programming
Programming language(s)key stroke (Turing-complete)
Memory register100
Program steps960
Other
Weight240 grams
Dimensions16.3x7.3x3.6 cm
TI-58
The TI-58C
TypeProgrammable
ManufacturerTexas Instruments
IntroducedMay 1977
Discontinued1983
CostUS$125
Calculator
Entry modeInfix
Precision13
Display typeLight-emitting diode
Display size10 digits
Programming
Memory register60
Program steps480
Other
Weight240 grams
Dimensions16.3x7.3x3.6 cm

The TI-59 is an early programmable calculator, that was manufactured by Texas Instruments from 1977. It is the successor to the TI SR-52, quadrupling the number of "program steps" of storage, and adding "ROM Program Modules" (an insertable ROM chip, capable of holding 5000 program steps). Just like the SR-52, it has a magnetic card reader for external storage. One quarter of the memory is stored on each side of one card.

The TI-58 (May 1977), and later TI-58C (1979), are cut-down versions of the TI-59, lacking the magnetic card reader and having half the memory, but otherwise identical. Although the TI-58C uses a different chip than the TI-58, the technical data remain identical. The "C" in a TI (or Hewlett-Packard) model name indicates that the calculator has a constant memory (or continuous memory, respectively) allowing retention of programs and data when turned off.

These calculators use a parenthesized infix calculation system called "Algebraic Operating System" (AOS), where, compared to the postfix RPN system used by other scientific calculators (such as HP), the operator enters calculations just as they are written on paper, using up to nine levels of parentheses.[1]

The calculator can be powered from an external adapter or from internal NiCd rechargeable battery pack (although the battery has to remain present when using the external AC adapter to avoid damage to the calculator circuitry).

  1. ^ TI-58 Leaflet (PDF), p. 2