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DATAMATH CALCULATOR MUSEUM |
TI-92 Expansion Port
The
TI-92 introduced early in 1996 featured a small
Expansion Port on the backside of its housing. With the complete address- and
data-bus of the M68000 compatible CPU available, upgrades of both the Operating
System and user memory capacity were made easy.
TI-92 I0696 module

Texas
Instruments used at the very beginning of the TI-92 market introduction OTP-ROM
(One-time Programmable Read-Only Memory) for the Operating System of the
calculator instead the later Mask-ROM soldered on the main printed circuit board
(PCB). The printed circuit board (PCB) of the module contains two integrated
circuits:
| OTP-ROM: 2*AT27C040, 256k*8, each |


The
TI-92 E module was introduced early in 1996 and added the choice of 5 user
languages (English, French, German, Italian and Spanish) and an additional 128k
User memory. The printed circuit board (PCB) of the module contains two
integrated circuits:
| ROM: IEC9895S-960819E, 1M*8 | |
| RAM: TC551001B, 128k*8 |

The
TI-92 II module was introduced early in 1996 and added the choice of 5 user languages (English, French, German, Italian
and Spanish) and an additional 128k User memory. The printed circuit board (PCB)
of the module contains two main integrated circuits:
| Flash-ROM: Sharp LH28F016S, 2M*8 | |
| RAM: TC551001B, 128k*8 |

The
TI-92 Plus module was announced November 7, 1997 and arrived mid-1998 in the
shelves for about $75. It boosted the TI-92 with the
enhanced Flash-technology into an user-upgradable calculator. Compared with the
pre-programmed Operating Systems of both the TI-92 and TI-92 II the Flash-memory
of the TI-92 Plus module could be re-programmed by the user with a simple
download cable connected to a personal computer. The printed circuit board (PCB)
of the module contains two main integrated circuits:
| Flash-ROM: Sharp LH28F016S, 2M*8 | |
| RAM: TC551001B, 128k*8 |
It took another year before the "real" TI-92
Plus calculator was introduced.
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If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, June 8, 2003. No reprints without written permission.