Texas Instruments RR-1 Spell-Checker

Texas Instruments introduced already in 1989 this powerful Spell-Checker RR-1. The later RR-2 added a Thesaurus to the Spell-Checker function. 

A much smaller product followed within 1 year, don't miss the PS-3000. 

What is a Spell-Checker? Type in a word and the Spell-Checker compares it immediately with roughly 97,000 words of its memory. 

We noticed some minor changes of the key printing during production time. Don;t miss the second edition of the RR-1 and focus on the printing of the [ON - OFF] key legend.

Dismantling this early Spell-Checker RR-1 reveals a rather complex printed circuit board (PCB) centered around a Z80 compatible Toshiba T84C00A microprocessor, a Toshiba TC531000 OTP-ROM with 128k Bytes capacity and a small RAM Sanyo LC3518 with 2k Bytes capacity. The single-chip display driver was assembled in reverse direction and hides its type. We assume that the chip was manufactured by Toshiba.

The TMPZ84C00A is an 8-bit microprocessor manufactured in Toshiba's low-power C-MOS Silicon gate technology featuring a power consumption of only 15 mA while operating at 6 MHz. The above sketched architecture was used in a lot of different products with just another balance of RAM and ROM capacity:

If you have additions to the above article please email: joerg@datamath.org.

© Joerg Woerner, Ocober 23, 2009. No reprints without written permission.