DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-1255
Date of introduction: | 1976 | Display technology: | LED-stick |
New price: | Display size: | 8 | |
Size: | 5.5" x 2.8" x
1.4" 138 x 70 x 35 mm3 |
||
Weight: | 3.9 ounces, 110 grams | Serial No: | 1003728 |
Batteries: | 2*AA NiCd | Date of manufacture: | wk 17 year 1977 |
AC-Adapter: | AC9130 | Origin of manufacture: | USA (LTA) |
Precision: | Integrated circuits: | TMS0972 | |
Memories: | 1 | ||
Program steps: | Courtesy of: | Ken H. Meine |
Texas
Instruments took in 1976 in conjunction with mathematics educators at two major
universities an initiative to introduce a group of 6 calculators for educational
use. Including the Little Professor,
the limited function ABLE calculator, the colorful TI-1205
and TI-1255, the TI-30 and the
sophisticated SR-51-II, these
calculators helped students understand and use math concepts from kindergarten
through college and career.
The TI-1255 is based on the TI-1250
but includes rechargeable NiCd-batteries instead the standard 9V block battery.
To enhance the readability of the keyboard both the size of the numerals and the
color-scheme was improved. Don't miss an early prototype of the
TI-1255 using still using the 9V battery.
Disassembling
this TI-1255 with
Date code 1777 LTA and manufactured in April
1977 in Lubbock, Texas reveals an internal construction identical with the TI-1205. Instead
of the 9V battery found in the original TI-1200, TI-1250
design, the TI-1255 makes use of 2 rechargeable, AA-sized NiCd (Nickel Cadmium)
batteries. The PCB (printed circuit board) adds both the charging circuit for
the batteries and a step-up converter to generate the 9V supply of the
TMS0972
single-chip calculating circuit.
Learn
more about the evolution of the TI-1250 between
June 1975 and its discontinuation in 1977.
Learn more about the different
Product Labels used with the TI-1250
- here at the Datamath Calculator Museum we classify the featured TI-1255 as
Hardware Version 3A, PCB Type 4 and Product Label Style 6.
The TI-1255 is one of the rarest members in the TI-12xx line
and was sold only in the US.
Fellow collectors - if you own a Texas Instruments TI-1255 calculator, please report us the serial number and date code from the back of the calculator for our Database.
Don’t miss the LADY 1200, a
design developed by marketing guys to attack women’s hand-bags and using the
same off-white housing part as this TI-1255.
On September 17, 2009 we were able to celebrate
reunion of the calculators featured in the TI Learning Center
Sales Leaflet CB-272 including three of the rarest portable electronic calculators.
TI-1255.
A rechargeable, full-function capability calculator with automatic
constant and 4-key memory.
Texas Instruments rechargeable TI-1255 is well-suited for students in fundamental mathematics curricula. It includes the same features as the TI-1205, plus independent memory and change-sign key for entering negative numbers. Using the TI-1255’s versatile memory system, students are able to store intermediate results and answers as they explore secondary level math topics. Students may add to [M+] or subtract from [M-] memory a displayed number without affecting the calculation in process. Stored numbers may be displayed by using memory recall [MR], and the memory can be cleared [MC] without clearing the calculator. Convenient algebraic entry allows students to enter problems in the same order they would write them on paper. A touch of the change-sign key [CS] changes the displayed number from positive to negative or vice versa, and the bright 8-digit display and large keyboard numerals offer good visibility. A
supplement learning package “Calculator Math™ Fundamental
Mathematics”, was developed and tested by the © Texas Instruments, 1976 |
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, September 30, 2020. No reprints without written permission.