The following document was prepared by Martin-Eric Racine.

Upgrading CA401059 ST RAM cards

Late-production TT030 were delivered with this versatile ST RAM card which could be assembled as 2 or 8 MB daughterboards, thanks to its clever PCB design.

The 2 MB version can be easily upgraded to 8 MB:

  1. Remove the old 256Kx4bit chips (TMS44C256-10).
  2. Install new 1Mx4bit chips (TMS44400DM-10).
  3. Switch the configuration headers to 8 MB.

This upgrade was prepared from various circuit schematics. While I didn't attempt it, I cannot see why it would fail. If you complete this upgrade sucessfully, please let me know.

11.01.1999:

Bernie Diotte confirms this is correct and that his upgraded daughterboard worked perfecly fine, once he remembered to switch the addressing jumpers to the 8 MB setting.


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