Abstract: A pattern sequence and state transition trigger generator provides a trigger when a specified transition from one pattern/state to another pattern/state occurs in a set of input signals. Decoders detect each specified pattern/state from the set of input signals to produce a prior value and a current value representing the transition. The prior value is slightly delayed and combined with the current value to produce an overlap when the specified transition occurs, which in turn generates the trigger.

Abstract: An advanced trigger circuit includes first and second trigger decoders, each being capable of triggering on one of respective first and second pluralities of continuous-time trigger events. In one embodiment, a programmable timer begins timing in response to an output signal of the first trigger decoder and generates an end-of-time signal at the expiration of its time period. A reset circuit is responsive to the end-of-time signal of the timer for resetting the first trigger decoder if the second selected continuous-time trigger event failed to occur before the end-of-time signal was generated. In another embodiment, a reset decoder generates a reset signal in response to an occurrence of a selected continuous-time trigger event. The reset circuit is responsive to the reset signal for resetting the first trigger decoder if the second selected continuous-time trigger event failed to occur before the reset signal was generated.

Abstract: A pressure-compensating drip irrigation hose (10) has a water supply passage (26) and a flow regulating channel (24) smaller than the water supply passage (26). The flow regulating channel (24) comprises at least one inlet section (28), at least one outlet section (32), and at least one nozzle section (34) between an inlet section (28) and an outlet section (32). The inlet section (28) comprises one or more openings (38) connecting the water supply passage (26) to the flow regulating channel (24). The outlet section comprises one or more openings connecting the flow regulating channel (24) to the exterior of the hose (10). Preferably the flow regulating channel (24) further comprises at least one turbulent flow section (30) between an inlet section (28) and an outlet section (32). The nozzle section (34) is preferably between an inlet section (28) and a turbulent flow section (30). A method for making the drip irrigation hose (10) is also provided.

Abstract: A self cleaning drip irrigation hose comprising an elongated strip of plastic film folded longitudinally to form first and second overlapping longitudinal margins. A first longitudinal bead partially seals the overlapping margin. A second longitudinal bead outboard of the first bead partially seals the overlapping margins. The first and second beads have a repeating longitudinal pattern that forms a flow regulating channel and opposing inlets spaced along the length of the first and second beads. Outlets from the flow regulating channel to the exterior of the hose are spaced from the inlets to create a pressure drop across the flow regulating channel. A third longitudinal bead outboard of the second bead completely seals the overlapping margin. The second and third beads form a water access channel to the inlets in the second bead such that the inlets in the first bead when plugged are back flushed by water flow through the inlets in the second bead.