TI-55
The TI-55 is a programmable calculator first manufactured by Texas Instruments in 1977. It has an LED display,[1] and weighs 6.4 ounces (180 grams). It is programmable to hold up to 32 key-codes that allow the user to repeat simple calculations with different values.[2]
 a TI 55-II | |
| Type | Programmable |
|---|---|
| Manufacturer | Texas Instruments |
| Introduced | 1977 |
| Discontinued | 1979 |
| Calculator | |
| Precision | 11 Floating point (within display) |
| Display type | LCD |
| Display size | 8+2 |
| CPU | |
| Processor | TI TMC1503NL |
| Programming | |
| Other | |
| Power supply | battery / cells |
| Power consumption | 2 LR44's |
| Weight | 84 grams (3.0 oz) |
| Dimensions | 147 mm × 71 mm × 22 mm (5.8 in × 2.8 in × 0.85 in) |
Variants
TI-55 II
The TI-55 II with LCD was introduced in 1981, but, like many other Texas Instruments calculators of this time, suffered from serious keyboard reliability problems. Several variants of the TI-55 II exist.
TI-55 III
The TI-55 III replaced the TI-55 II in the USA in 1986. It features redesigned keyboard mechanics, thereby eliminating the common "bouncing keys" fault of prior models. Several variants of the TI-55 III exist.
TI-56
The TI-56 is a European variant of the TI-55 III manufactured since 1986. It was also offered free of charge in exchange of faulty Texas Instruments calculators of a similar class like the TI-54 in Europe in 1986.