Texas Instruments Constant Memory Module

Date of introduction:  Never
 (Announced: May 1982)
Display technology:  
New price:  MSRP: $50.00 Display size:  
Size:  1.3" x 1.25" x 0.55"
 33 x 32 x 14 mm3
Weight:  0.45 ounces, 13 grams Serial No:  
Batteries:  LF-1/2W Date of manufacture:  wk 37 year 1982
AC-Adapter:   Origin of manufacture:  USA (ATA)
Precision:   Integrated circuits:  2*TP0531
Memories:  148-0    
Program steps:  0-1184 Courtesy of:  Joerg Woerner

The Constant Memory Module was developed by Texas Instruments for its TI-88 Programmable calculator system and available as an option the calculator.

Don't miss earlier versions of the Constant Memory Modules included with TI-88 calculators from the DVT (Design Validation Test) and EVT (Engineering Validation Test) builds.

Dismantling this Constant Memory Module manufactured in September 1982 by Texas Instruments in their Abilene, Texas facility reveals a printed circuit board (PCB) to accommodate up to two TP0531/TP0532 Memory Chips. The PCB is populated with two TP0531 Read/Write Memories (RAMs) with a capacity of 4,800 Bits or 600 Bytes, each and a Sanyo 3 Volts lithium battery from the type LF-1/2W with 24.0 mm diameter and a thickness of 3.0 mm - matching today's CR2430 cells.



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Joerg Woerner, October 12, 2019. No reprints without written permission.