Logically Determined Design: Clockless System Design with NULL Convention Logic

Appendix A

Logically Determined Wavefront Flow

Wavefronts spontaneously flow through cycles composed with shared completeness paths by virtue of the cycles, themselves, continuously striving to transition. The logical behavior of each completeness path implements a four-phase handshake protocol [35,40] that provides a conveniently intuitive context for talking about the behavior of wavefront flow.

A.1 SYNCHRONIZATION

Figure A.1 reviews the 2NCL the registration stage, which forms the shared completeness path spanning the monotonically transitioning data path. The 2NCL version of the four-phase handshake protocol is shown in Figure A.2 as a polite conversation between registration stages.

A.2 WAVEFRONTS AND BUBBLES

This polite conversation, together with the completeness relationships of the registration stages, results in a forward flow of wavefronts and a backward flow of requests. The backward flowing request is called a bubble. Wavefronts flow forward through bubbles and bubbles flow backward through wavefronts.

A wavefront is the part of a DATA or NULL wave propagation that is being stably maintained by a same phase request. A wavefront cannot be overwritten by a following opposite phase wavefront.

A bubble is the part of a DATA or NULL wave propagation that is no longer being ...