DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-74 BASICALC
Date of introduction: | 1986 | Display technology: | LCD dot matrix |
New price: | $135.00 (SRP 1988) DM 348.00 |
Display size: | 31 (10 + 3) |
Size: | 3.8" x 8.0" x
1.0" 96 x 204 x 25 mm3 |
||
Weight: | 10.3 ounces, 290 grams | Serial No: | 0001522 |
Batteries: | 4*AAA | Date of manufacture: | mth 06 year 1987 |
AC-Adapter: | Origin of manufacture: | Taiwan (I) | |
Precision: | 13/14 | Integrated circuits: | CPU:
TMC70009 ROM: HN61256 RAM: HM6264 DISPLAY: HD44780, HD44100 |
Memories: | 8kB RAM, 32kB ROM | ||
Program steps: | Courtesy of: | Joerg Woerner | |
Download leaflet: | (US: 1.7M Bytes) |
The
TI-74 BASICALC is a cross-over of the earlier CC 40 Compact Computer and a
conventional calculator.
You have both a BASIC-language computer with a
total of 8k Byte memory and a calculator mode with algebraic input and immediate output
on the huge alphanumerical display.
The other features of the TI-74 are similar to its sibling TI-95 PROCALC:
You may install RAM or ROM-cartridges in the
expansion port or connect the PC-324 printer through
the Dock-Bus to the
computer. The maximum capacity of the TI-74 BASICALC is 16k Bytes of memory.
The TI-74 BASICALC System uses the following components:
Part | New price | Description |
PC-324 | $115.00 (SRP 1988) | 24-column thermal printer |
PA-201 | (SRP 1988) | Power adapter adaptor for TI-74, TI-95 |
AC9201 | $19.00 (SRP 1988) | Mains adapter for PC-324 |
TP-324 | $6.00 (SRP 1988) | Thermal paper for PC-324 |
CI-7 | $35.00 (SRP 1988) | Cassette Interface |
CM-8 | $50.00 (SRP 1988) | 8k Constant Memory Module (RAM) |
Mathematics | $50.00 (SRP 1988) | Library (ROM) |
Statistics | $50.00 (SRP 1988) | Library (ROM) |
Learn Pascal | $50.00 (SRP 1988) | Library (ROM) |
Finance | $50.00 (SRP 1988) | Library (ROM) |
Chemical Engineering | $50.00 (SRP 1988) | Library (ROM) |
TI-892F | $114.95 (SRP 1988) | 32k programmed EPROM Module (First) |
TI-892D | $84.95 (SRP 1988) | 32k programmed EPROM Module (Dupl.) |
TI-892E | $76.95 (SRP 1988) | 32k programmed EPROM Module (Bulk) |
In
1987 Texas Instruments introduced Programmable
Calculator News, a service for TI-74 and TI-95 users to feature program
listings, technical articles, question and answer segments, new product reviews, and user comments. All
Programmable Calculator News are
available for free download as a service provided by the Datamath Calculator
Museum.
Dismantling the featured TI-74 BASICALC manufactured in June 1987
by Invented Corporation in
Taiwan, reveals a rather complex
design with two printed circuit boards (PCB's).
The
HN61256
ROM
of this TI-74 BASICALC was manufactured by Hitachi and offers a capacity of
32k Bytes with a rather slow access time of up to 3.5 us. With the TMC70C40 CPU
lacking a "wait-state" mechanism, incorporates the TMC70C46 additional circuitry
to slow down the CPU clock cycle while accessing the ROM chips.
RAM
(Random Access Memory): The RAM is used as data memory and is used to store both
variables, user programs and intermediate results. This
TI-74 BASICALC makes use of
HM6264 manufactured by Hitachi, Japan
DISPLAY:
The display drivers of the
TI-74 BASICALC are located on the second (lower) PCB and use a combination of a Hitachi HD44780 LCD Controller and one additional Hitachi
HD44100 LC Driver. The HD44780 contains the character generator for 208
characters in a 5x8 dot matrix, 32 characters in a 5x10 font, RAM for a maximum
of 80 characters and the driver electronics for 16 characters. The HD44100 adds
an additional 40 segment drivers for the remaining characters.
A special OEM-version of the TI-74 was sold as TI-74S and TI-74S ALLIANZ. Interested in customizable calculators and computers or even Programmable Data Terminals? Don't miss the TI-78 and TI-78P.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, December 5, 2001. No reprints without written permission.