VSM reader

VSM reader

Reader module for VSM memories

Allow access to VSM memories
(Texas Instruments Voice Synthesis Memory)

For TMS6100 / TMS6125 circuits and derivatives.


The VSM memories (Voice Synthesis Memory) produced by Texas Instruments are mainly used in vocal applications, generally associated with a TMS5100, TMS5200 or TMS5220 synthesis circuit.

These circuits have received specific markings in the manufacturer's consumer products. Thus the TMS6100 / TMS6125 are marked TMC0350 / TMC0355 in the "speak and spell" and CDxxxx, CMxxxx or VMxxxx in the different modules.

They use PMOS technology and must be supplied with negative voltage. Their mode of operation is very particular, with 4-bit addressing and serial data output.

To be able to read these memories, we have developed a small adapter module that can be used with the NG test bench.

VSM adapter

The VSM adapter

The module has a DIP-16 slot for testing TMS 6125 and a DIP-28 slot for testing TMS 6100. A connector is also provided for directly connecting the extension modules of the "speak and spell". It takes place on the component tester, replacing a standard DIP-24 box.

The module loaded with a TMS 6125.
VSM adapter for TMS6125

The module loaded with a TMS 6100.
VSM adapter for TMS6100

Reading a "Speak & Spell" module.
Speak and Spell module

Usage with Pinprobe and VisualBench

VSM components are recognized by the pinprobe test bench and can be processed like any other ROM memory. The VisualBench software makes it easy to perform the test, reading and saving the content of these memories.

TMS 6125 in pinprobe

Read the TMS 6125 with VisualBench


This achievement is not publicly available, in any form whatsoever (free or paid).


Last update of this page: February 23th, 2021

French Tech


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