Sam, Chuck designed the Novix but the Harris RTX 2000, which is very similar, was designed by others.
These are 16-bit chips (the Novix addressed 128 KB) that use dedicated stack memories, that's 3 ports to memory total. The RTX puts the stacks on chip.
The nice thing about these CPUs is they can do stack, alu, and return in parallel, interrupts are cheap, timings are predictable, and programming model is nice if you like Forth. One disadvantage of the design is that clock rate is limited. RAM fetch and instruction processing have to fit between pulses meaning RAM has to be approx twice as fast as clock.
These are 16-bit chips (the Novix addressed 128 KB) that use dedicated stack memories, that's 3 ports to memory total. The RTX puts the stacks on chip.
The nice thing about these CPUs is they can do stack, alu, and return in parallel, interrupts are cheap, timings are predictable, and programming model is nice if you like Forth. One disadvantage of the design is that clock rate is limited. RAM fetch and instruction processing have to fit between pulses meaning RAM has to be approx twice as fast as clock.