Texas Instruments TMC0598


With the TMC05xx building blocks Texas Instruments created a novel architecture for scalable scientific calculators. The architecture uses minimum a 2 chip design with the Arithmetic chip TMC0501E and the SCOM (scanning read only memory) but was expandable to a maximum of 8 SCOM's, additional RAM as program memory for programmable calculators, additional RAM for general purpose registers and even a chip driving a printer. 

The up to four TMC0598 MULTI-REGISTER chips provide user program storage and user memory storage in the TI-58 and TI-59. Each chip contains 1920 bits of read/write memory holding either 240 program steps or 30 data registers.


TI-58, TI-59

Calculator Program steps Data memory TMC0598
TI-58 0-480 60-0 2
TI-59 160-960 100-0 4
TI-5230  t.b.d. t.b.d. 7


Technical Specification

Item Min Typ Max Unit Comments
VSS   0   V  
VDD -10.5 -10.0 -9.5 V  
PHI1, PHI2   225 230 kHz Opposite phases


The TMC0598 uses a standard DIP-16 package.

Pin Description

Pin IO Function Pin IO Function
1 V Negative Voltage VDD 16 I External access
2 I Calculating status 15 I not connected
3 I Clock Input 1 14 I not connected
4 I Clock Input 2 13 O Instruction words
5 IO SCOM Interface D0 12 I Bank-Select 1 (VSS,nc)
6 IO SCOM Interface D1 11 I Bank-Select 0 (VSS,nc)
7 IO SCOM Interface D2 10 IO SCOM Interface D3
8 V Common Voltage 9 V Negative Voltage VDD


If you have additions to the above datasheet please email:

Joerg Woerner, February 02, 2001. No reprints without written permission.