1. A snap action switch which includes upper and lower nonsnap contacts, and which includes a snap action actuator having an actuation location and a tripping leg and a middle snap contact on the tripping leg, said middle contact lying between said upper and lower contacts and said middle contact being moveable between a down position against said lower contact and an up position against said upper contact, said actuator being constructed to snap said middle contact from said down position to said up position when said actuation location is depressed beyond a first snap height and to snap said middle contact from said up position to said down position when said actuation location is allowed to rise beyond a second snap height, comprising:
means for varying the height of one of said nonsnap contacts, to thereby vary one of said snap heights at which said middle contact snaps.
2. A snap action switch comprising:
a frame;
an operator that is moveably mounted in said frame and that has an operator triggering end;
a spring that is mounted in said frame and that has a frame-abutting end coupled to said frame and an operator-abutting end coupled to said operator and urging said operator end upwardly;
upper and lower unsnap contacts mounted on said frame;
a snap action actuator having an actuation location lying immediately below said operator end, to be moved downward by said operator end, said actuator having a trigger leg with a middle snap contact thereon lying between said upper and lower contacts and moveable between a down position against said lower contact and an up position against said upper contact, said actuator constructed to snap said middle contact from said down position to said up position when said actuation location is moved down beyond a first snap height, and to snap said middle contact from said up position to said down position when said actuation location rises beyond a second snap height, comprising:
means for adjusting the position of said upper contact to position said upper contact at higher and lower positions relative to said lower contact, to thereby change the height at which said middle contact snaps down.
3. The switch described in claim 2 wherein:
said means for adjusting includes a beam with a first beam location fixed to said frame, a second beam location that is spaced from said first locations with said upper contact being fixed to said beam at said beam second location, and a beam third location that is spaced from said beam first location, said means for fixing also including a screw that can be tightened to press down said beam third location.
4. The switch described in claim 2 wherein:
said frame has a fluid inlet, and including a membrane with a periphery fixed to said frame, and with a first membrane side exposed to said fluid and an opposite membrane side that applies force to said operator to urge said operator downwardly against said spring force;
said snap action actuator snaps said middle contact down against said lower contact when said operator moves upward beyond an upper actuation height (112), and said means for adjusting adjusts the height of the said upper contact to adjust said upper actuation height.
5. A method for use with a snap action switch arrangement which includes a frame, an operator that is moveably mounted in the frame, a spring coupled to the operator and frame and biasing the operator in a downward direction, upper and lower unsnap contacts mounted on said frame, and a snap action actuator having an actuation location lying immediately below said operator to be moved downward by said operator, said actuator having a trigger leg with a middle snap contact thereon lying between said upper and lower unsnap contacts and moveable between a down position against said lower contact and an up position against said upper contact, said actuator constructed to snap said middle contact from said down position to said up position when said actuation location is moved down beyond a first snap height, and to snap said middle contact from said up position to said down position when said actuation location rises beyond a second snap height, the method being useful to adjust said second snap height at which said middle contact snaps to said down position, comprising:
adjusting the height of said upper unsnap contact relative to said snap action actuator.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An apparatus to train a memory link, comprising:
a signal alignment unit, coupled to a plurality of signal lines of the link, operable to
align a read data strobe signal of the link on a center of a read data eye of the link;
align a receive enable signal of the link with a time that data returns on one or more data lines of the link after a column address strobe signal is sent to a memory coupled to the link;
align a write data strobe signal of the link with a clock signal of the link; and
align a center of a write data eye of the link with a write data strobe of the Link;
an alignment timeout timer to time out of one or more of the align operations if one or more of the align operations takes longer than a predetermined maximum time designated for an align operation; and
an alignment error register to store one or more alignment error flags, each alignment error flag being designated to report an alignment error for one of the one or more align operations, wherein an alignment error flag is set if the time spent on its designated align operation exceeds the predetermined maximum time.
2. The apparatus of claim 1, wherein the signal alignment unit further comprises a plurality of delay locked loops, each one of the plurality of delay locked loops being pairingly coupled to one of the plurality of signal lines.
3. The apparatus of claim 2, wherein the signal alignment unit is further operable to
select a reference signal line; and
shift a first signal phase transmitted on a first signal line of the plurality of signal lines, utilizing the delay locked loop pairingly coupled to the first signal line, relative to a phase of a reference signal transmitted on the reference signal line to align the first signal phase with the reference signal phase.
4. The apparatus of claim 1, wherein the signal alignment unit is further operable to align the receive enable signal, the read data strobe signal, the write data strobe signal, and the center of the write data eye for each of a plurality of ranks in the memory.
5. The apparatus of claim 1, wherein the signal alignment unit further comprises an alignment complete flag, wherein the signal alignment unit sets the alignment complete flag when all signal alignment operations are complete and no error flags are set in the alignment error register.
6. The apparatus of claim 1, wherein the signal alignment unit performs one or more of the signal alignments in response to a setting in a basic inputoutput system (BIOS) to align a signal.
7. The apparatus of claim 1, wherein the signal alignment unit performs one or more of the signal alignments dynamically in response to a system event.
8. A method of training a memory link, comprising:
aligning a read data strobe signal of the link on a center of a read data eye of the link;
aligning a receive enable signal of the link, the link being comprised of a plurality of signal lines, with a time that data returns on one or more data lines of the link after a column address strobe signal is sent to a memory coupled to the link;
aligning a write data strobe signal of the link with a clock signal of the link;
aligning a center of a write data eye of the link with a write data strobe of the link;
timing out of one or more of the align operations if one or more of the align operations takes longer than a predetermined maximum time designated for an align operation; and
storing one or more alignment error flags, each alignment error flag being designated to report an alignment error for one of the one or more align operations, wherein an alignment error flag is set if the time spent on its designated align operation exceeds the predetermined maximum time.
9. The method of claim 8, further comprising:
selecting a reference signal line; and
shifting a first signal phase transmitted on a first signal line of the plurality of signal lines relative to a phase of a reference signal transmitted on the reference signal line to align the first signal phase with the reference signal phase.
10. The method of claim 8, further comprising:
aligning the receive enable signal, the read data strobe signal, the write data strobe signal, and the center of the write data eye for each of a plurality of ranks in the memory.
11. The method of claim 8, further comprising setting an alignment complete flag when all signal alignment operations are complete and no error flags are set in the alignment error register.