Texas Instruments TI-73 ViewScreen™ (Engineering Sample)

Date of introduction:  1998 Display technology:  LCD dot matrix
New price:  $150.00 (SRP 2008) Display size:  8 * 16 characters
Size:  7.2" x 3.2" x 0.95"
 182 x 81 x 24 mm3
Weight:  6.6 ounces, 186 grams Serial No:  
Batteries:  4*AAA + CR1620 (35mA) Date of manufacture:  mth 01 year 1998
AC-Adapter:   Origin of manufacture:  Taiwan (I)
Precision:  14 Integrated circuits:  CPU: Zilog Z84C0008
 ASIC: TI REF 9815455
 Flash: AM29F400
 RAM: SRM2B256
 Display: Toshiba T6A04
Program steps:  25k Bytes, 218k Bytes Flash ROM Courtesy of:  Xavier Andréani

This TI-73 ViewScreen Calculator (VSC) Prototype carries on the backside a label "Engineering Sample" but is otherwise identical with the TI-73 VSC.

Four ViewScreen panels were available in 2008:

Panel 1: TI-73 VSC, TI-73 Explorer VSC, TI-80 VSC, TI-82 VSC, TI-83 VSC,
   TI-83 Plus VSC, TI-83 Plus Silver Edition VSC, TI-84 Plus VSC,
   TI-84 Plus Silver Edition VSC
Panel 2: TI-89 VSC, TI-89 Titanium VSC, TI-92, TI-92 Plus, Voyage 200
Panel 3: TI-85 VSC (2nd design), TI-86 VSC
Panel 4: TI-Nspire, TI-Nspire CAS, TI-Nspire Touchpad, TI-Nspire CAS Touchpad

As an alternative the TI-Presenter video adapter connects to a TV or other projection device with a video input port. 

From a technical point of view the TI-73 VSC is almost identical with the students TI-73. The main difference you notice is a bulgier bottom shell of the calculator housing to accommodate the ViewScreen electronics and connector.

Dismantling the TI-73 VSC reveals a small printed circuit board (PCB) with two driver chips connected with a flexible cable to the display PCB of the calculator.

Disassembling this TI-73 VSC Engineering Sample manufactured in January 1998 by Inventec Corporation in Taiwan reveals the original design of the TI-73 using 5 main Integrated Circuits:

Zilog Z84C00 microprocessor
TI REF 9815455 ASIC
512k Bytes Flash ROM
32k Bytes RAM
Toshiba T6A04: Single-chip 64*120 pixel display driver

Please notice the additional 5-pin Integrated Circuit mounted with double-tape on the ASIC package and connected with various "blue wires" tot the circuity.


1.60 (December 16, 2001)

You can check the ROM version of your TI-73 VSC using the following key sequence and reading the number on your screen:

[2nd] [MEM] [1]

Information provided by and Xavier Andréani.

Exam acceptance:

The TI-73 VSC is permitted (as of May 30, 2013) for use on SAT, ACT, PSAT and AP exams but is not recommended for the AP exam.

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© Joerg Woerner, May 31, 2013. No reprints without written permission.