Solid State Software and Constant Memory Expansion Modules™


The TI-58 and TI-59 calculators introduced in 1977 a novelty, the Solid State Software Modules™ with up to 5,000 program steps. The TI-88 took this concept two steps further and included two module ports providing the user with the unprecedented capability of installing up to 30,000 steps of pre-programmed Solid State Software, or, by installing Texas Instruments' new Constant Memory Expansion Modules, over 2,000 program steps or nearly 300 data registers could be added. 

The Master Library, known as "Module -1-", with 12 different programs was included with the TI-88. These programs covered a broad range of interests and provided an overview of the calculator's capabilities:

Table of Contents (alphanumeric reference)
Diagnostic (Internal and installed memory)
Moving Averages
Root Finder (Real roots of functions)
Numeric Integration (Romberg method)
Matrices (9x9 with internal memory, 15x15 with CRAM installed)
Linear Regression (up to 9 predictors, 13 with CRAM installed)
Random Number Generator
Codebreaker (Guess 4 digit number)
Sorting (Numeric lists)
Function Evaluator (Printing plots with the PC-800 printer)

Seven additional Solid State Software Modules™, known as "Module -2- to -8-" were announced from Texas Instruments.


Solid State
Software Module

Description / Application

IC /
Price Module Manual Reference Guide
 CROM -1- Master Library TP532
 CROM -2- Statistics Library TP532 $40    
 CROM -3- Electrical Engineering Library TP532 $40    
 CROM -4- Finance Library TP532 $40    
 CROM -5- Surveying Library TP532 $40      
 CROM -6- Mathematics Library TP532 $40    
 CROM -7- PGM Development Library
(Translate TI-59 programs)
TP532 $40      
 CROM -8- Chemical Engineering Library TP532 $40      

Constant Memory
Expansion Module

Description / Application

ICs Price Module Manual Reference Guide
 CRAM Constant Memory:
1184 program steps or
148 data memories
TP531, TP531 $50    


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© Joerg Woerner, October 8, 2019. No reprints without written permission.