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Texas Instruments TI-66 PROGRAMMABLE
Date of introduction: | May 1983 Available: August 1983 |
Display technology: | 14-segment LCD |
New price: | $69.95 (SRP 1983) DM 112.65 (UVP 1983) |
Display size: | 10 (8 + 2) |
Size: | 3.4" x 5.7" x 0.6" 86 x 145 x 15 mm3 |
||
Weight: | 3.7 ounces, 105 grams | Serial No: | 296531 |
Batteries: | 2*LR44 | Date of manufacture: | mth 07 year 1984 |
AC-Adapter: | Origin of manufacture: | Japan | |
Precision: | 13 | Integrated circuits: | Toshiba T6875(A), TC5514A |
Memories: | 0-64 | ||
Program steps: | 512-0 | Courtesy of: | Joerg Woerner |
Download leaflet: | (US: 0.7M Bytes) | Download manuals: |
(US: 12.7M Bytes) (US: 11.5M Bytes) (US: 4.5M Bytes) |
Texas
Instruments introduced the TI-66 Programmable in 1983 as successor of the
legendary TI-58 and TI-59
calculators. The TI-66 Programmable compares best with the TI-58C,
the latest member of the TI-58 family manufactured between 1979 and its
discontinuation in 1983.
TI-58C | TI-66 | |
Introduction | 1979 | 1983 |
Weight | 8.5 ounces, 240 grams | 3.7 ounces, 105 grams |
Precision | 13 digits | 13 digits |
Batteries | 3 * AA NiCd | 2 * LR44 |
Display size | 10 (8 + 2) LED | 10 (8 + 2) LCD |
Memories | 0 - 60 | 0 - 64 |
Program steps | 480 - 0 | 512 - 0 |
Printer | PC-100C | PC-200 |
The TI-66 Programmable was the first Texas Instruments calculator in landscape orientation, probably inspired by Hewlett Packard's very successful "Voyager" series (HP-10C, HP-11C, HP-12C, HP-15C, and HP-16C) of programmable calculators introduced in 1981. The next design iteration of the TI-66 Programmable led to both the TI-30 Galaxy in 1984 and TI-62 Galaxy in 1986.
Dismantling
the featured calculator manufactured in July 1984 in Japan reveals two
surprises! The whole electronics of the TI-66 Programmable was squeezed into
just two chips labeled Toshiba T6875 resp. Toshiba TC5514A and the printed
circuit board (PCB) shows a very prominent Toshiba logo.
The
partitioning of the two Integrated Circuits is rather obvious, the Toshiba T6875
is a 4-bit Microcomputer with internal ROM
(Read-Only Memory), integrated display driver, keyboard scanning logic and
interface to an external RAM (Random Access Memory) circuit. The ROM is used for
the calculator "operating system" and constants, while the RAM stores
both the user program and user data. We know TI-66 Programmable calculators with
later manufacturing dates sporting a T6875A chip, instead. The switch happened
in Summer 1984, known T6875 date codes are till April 1984 and known T6875A date
codes are after August 1984 and at least till July 1986. Thanks, Brian!
The
featured
TI-66 Programmable manufactured in July 1984 makes use of a TC5514A manufactured
by Toshiba, Japan. The capacity of the memory is 1k * 4 bits.
A nice feature of the calculator is the connectivity to the
serial printer PC-200 known from the financial calculator BA-55.
Don't miss the talking Calcu-Talk based on the TI-66.
If you are interested in the calculating accuracy of scientific calculators don't miss the Calculator forensics.
Read more about the calculators developed, manufactured and / or sold by Toshiba.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, December 5, 2001. No reprints without written permission.