This is a 32k memory expansion for the sideport of the vintage TI-99/4a personal computer.  Functionally equivalent to TI's 32k expansion ram, this device plugs into the sideport of the TI with an edge card connector.  It operates with +5v, using about 5-10mah either drawing power from the computer or through the external power jack when plugged into a 5vdc power supply (not included).  Selection of either configuration is performed by setting the desired jumper configuration (found on the board) to either take power from external 5.5/2.1mm tip-positive power jack, or the TI-99/4A sideport.

With this device plugged into your TI99/4A a user can run many of the games on the 2048k cart or any of the 6 multicart games cartridges. Many of the newer cartridge titles also require a 32k expansion and will work with this device.

This memory expansion will function with the TI99 Speech Synthesizer, however the TI-99/4A speech synthesizer does not pass power on pin #1.  This means that the memory expander cannot draw power from the computer to power itself (unless the power jumper modification has been performed on your speech synthesizer).  The work-around is simple however.  Get yourself a 5VDC power supply and operate the memory expander on external power when plugged into your speech synthesizer (or modify it yourself to pass power).

The memory expander is tested as shown with memory testing software, and further tested with a few 32K games.

Texas Instruments TI 99/4A 32K Sidecar Memory Expansion Card

  • Product Code: TI.32K.Expander
  • Availability: In Stock
  • $83.99

  • Ex Tax: $79.99

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