It is a two-stack machine, each stack 256 words deep each, that supports direct execution of Forth. Subroutine calls and returns only take one processor cycle and it also has a very low and consistent interrupt latency of only four processor cycles, which lend it well to realtime applications.
In 1983, Chuck Moore implemented a processor for his programming language Forth as a gate array. As Forth can be considered a dual stack virtual machine, he made the processor, Novix N4000, as a dual-stack machine. In 1988, an improved processor was sold to Harris Semiconductor, who marketed it for space applications as the RTX2000.
Example spacecraft that use the RTX2010 
- Rash, James. "Space-Related Applications of Forth". NASA Goddard Space Flight Center. Retrieved 2008-10-15.
- Koopman, Philip. "Stack Computers: the new wave, Chapter 4.5 Architecture of the Harris RTX 2000". Retrieved 2008-10-15.