Texas Instruments TI-5040 (Version 2)

Date of introduction:  June 1978 Display technology:  Fluorescent
New price:  $149.95, 109.95
 DM 498.00
Display size:  10
Size:  9.5" x 9.2" x 2.7" Printer technology:  Thermal TP-20225, TP-27225
Weight:  3 pounds 5 ounces Serial No:  1409135
Batteries:   Date of manufacture:  wk 20 year 1981
AC-Adapter:  120 V Origin of manufacture:  USA (MTA)
Precision:  10 Integrated circuits:  TMC0261
Memories:  1 + 1    
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (US: 6.0M Bytes)

The original TI-5040 desktop printing calculator received in 1978 an internal redesign to reduce manufacturing costs. The TI-5040 was a great success for Texas Instruments, it was manufactured more than 5 years before its successor, the TI-5142 was introduced. Later models like the TI-5040 II or the TI-5130 had shorter life cycles.

Dismantling this TI-5040 (Version 2) manufactured in May 1981 by Texas Instruments in Midland, Texas reveals a very clean design using one printed circuit board (PCB) and centered around a TMC0261 single-chip calculator circuit based on the TMC0980 family introduced with the TI-30 and related to the TMC0270 family used with the Speak & Spell.

The internal design of the original TI-5040 uses two PCBs and two members of the famous TMS1000 Microcomputer family. The first chip labeled TMC1115 is manufactured in PMOS (p-channel metal-oxide-semiconductor) technology similar to the original Canon Pocketronic and features 2k*8 Bits ROM plus 128*4 bits RAM in a 28-pin DIP (Dual In-line Package) housing while the second chip labeled TMS1276 combines half the memory capacity (1k*8 Bits ROM and 64*4 bits RAM) with some extra Input/Output lines and drivers for the VFD in a 40-pin DIP housing.

While the overall appearance of the TI-5040 didn't change, offers the bottom-side of the housing an easy indication of the Version of the TI-5040:

Version 1: Printed label with manufacturer/model info in the center of the housing.
   No cut-out for the printer paper roll
Version 2: Manufacturer/model info molded into the left side of the housing.
   Cut-out for the printer paper roll on the right side of the housing

The TI-5220 printing desktop calculator with similar specifications but sporting a 12 digits display was introduced in 1977 together with its huge sibling TI-5225. Don't miss the TI-5135 introduced in 1980.

Even Texas Instruments never mentioned the rare TI-500, a printing calculator introduced already in 1974.

Find here an excerpt from the Texas Instruments Incorporated leaflet CL-199J dated 1981:


Offers the best of two worlds. An easy-to-read display. A printed tape.

For quick calculations use the large bright green 10-digit display, with commas and a floating decimal point. Or when the tape is needed, the whisper-quiet thermal printer delivers a crisp, clean copy of your calculations.
Special features to help solve business calculations or auditing problems include: A four-function memory. An independent add register (to simplify extensions, cross-footing and invoices). An automatic constant. A percent key. This combination of memory and independent add register results in a powerful "dual memory" capability.

Texas Instruments, 1981

horizontal rule

If you have additions to the above article please email:

Joerg Woerner, December 5, 2001. No reprints without written permission.