The LEGO Company does no longer offer technical support to advanced users on the historical MINDSTORMS range, specifically those using the SDK 2.5 (RCX™ and Scout™), and Spybotics™ range. Related tools and documentation were removed from MINDSTORMS website in 2008.
Here below you
will find these tools. By downloading them, you agree with the
Contains various documentation on RCX2 and Spybotics byte codes and LASM, as well as documentation, libraries and header files for PC to brick communications. Also includes RCX2 firmware (firm0328.lgo) that gives more capability to your RCX (even older versions).
Download SDK2.5 (9Mb)
Updated USB Tower Windows drivers
These drivers solves an issue occurring with HyperThread or multicore CPUs.
RIS 2.0 XP Patch
These patch should help you getting Robotics Invention System run under Windows XP.