What is claimed is:
1. A probe unit for measuring impedance for a printed wiring board, comprising:
a probe having a first and a second contact styli to be contacted with a first and a second predetermined points on the printed wiring board, the styli being fixed to the probe with a resilient member;
a turn disk having a turn center and a first position on a board-side face of the turn disk, the probe being disposed at the first position;
a turn device for turning the turn disk around the turn center such that the probe turns so that the contact styli turn substantially parallel to a measurement face of the printed wiring board; and
a moving device for moving the probe toward the measurement face of the printed wiring board such that the first and second contact styli are contacted with the predetermined points;
wherein the turn disk has a second position at which the probe can be disposed by being shifted from the first position and;
wherein the first position is farther from the turn center than the second position such that the probe is turned with a larger radius of curvature at the first position.
2. The probe unit according to claim 1, wherein the turn disk comprises a shift device shifting the probe from the first position to the second position in a substantially continuous manner.
3. The probe unit according to claim 2, wherein the shift device comprises:
a shift rail between the first and the second position; and
a probe moving device for moving the probe along the shift rail.
4. The probe unit according to claim 1, wherein the turn disk comprises a shift device shifting the probe from the first position to the second position in a substantially discontinuous manner that the probe is apart from the turn disk at least once while the probe is shifted.
5. The probe unit according to claim 1, wherein the probe has a third contact stylus to be contacted with a third predetermined points on the printed wiring board, the third contact stylus being fixed to the probe with another resilient member.
6. The probe unit according to claim 5, wherein at least one of the three styli can be fixed to another position on the probe by being shifted from an original position of the shifted stylus on the probe such that the shifted stylus can be contacted with another predetermined point on the printed wiring board.
7. The probe unit according to claim 1,
wherein the turn disk and the turn device are moved together by the moving device; and
wherein the turn device comprises:
a motor causing a turning driving force;
a belt transmitting the turning driving force;
a pulley being connected to the turn disk and receiving the turning driving force from the belt such that the turn disk can be turned around the turn center; and
a turn main body supporting the pulley rotatably with a bearing.
8. The probe unit according to claim 7,
wherein the moving device comprises:
a second motor causing a second turning driving force;
a second belt transmitting the second turning driving force;
a ball screw having a second pulley receiving the second turning driving force from the second belt; and
a mount member on which the turn main body is mounted.
9. An impedance measuring device for a printed wiring board, comprising the probe unit of claim 1, the measuring device further comprising:
a probe unit moving device for moving the probe unit substantially parallel to a measurement face of the printed wiring board; and
a board holding device for holding the printed wiring board to be measured;
wherein the probe unit moving device comprises:
an X-rail guiding the probe unit in an X-axis direction;
an X-driving device moving the probe unit along the X-rail;
a Y-rail guiding the probe unit in a Y-axis direction;
a Y-driving device moving the probe unit along the Y-rail; and
a control unit controlling the turn device, the moving device, X-driving device, and the Y-driving device.
10. The impedance measuring device according to claim 9,
wherein the turn disk comprises a shift device shifting the probe from the fist position to the second position in a substantially continuous manner;
wherein the shift device comprises:
a shift rail between the first and the second position; and
a probe moving device for moving the probe along the shift rail; and
wherein the control unit integrally controls the probe moving device.
11. A probe unit for measuring impedance for a printed wiring board, comprising:
a probe having a connecting portion and a first and a second contact styli to be contacted with a first and a second predetermined points on the printed wiring board;
a turn disk having a turn center and a mounting position, on which the probe is mounted with the connecting portion being fixed to the mounting position at a first angle relative to the turn disk;
a turn device for turning the turn disk around the turn center such that the probe turns so that the contact styli turn substantially parallel to a measurement face of the printed wiring board; and
a moving device for moving the probe toward the measurement face of the printed wiring board such that the first and second contact styli are contacted with the predetermined points;
wherein the probe can be mounted on the mounting position such that the connecting portion is fixed to the mounting position at a second angle relative to the turn disk; and
wherein at least one distance between the turn center and one of the styli is changed by fixing the connecting portion of the probe at the second angle.
12. The probe unit according to claim 11, wherein the turn disk comprises a spinning device turning the probe from the first angle to the second angle in a substantially continuous manner.
13. The probe unit according to claim 12, wherein the spinning device comprises:
a pivot axis of the connecting portion, around which the probe is turned;
a probe spinning device for turning the probe around the pivot axis; and
a lock notch securing a turning position of the probe.
14. The probe unit according to claim 11, wherein the probe has a third contact stylus to be contacted with a third predetermined points so on the printed wiring board, the third contact stylus being fixed to the probe with another resilient member.
15. The probe unit according to claim 14, wherein at least one of the three styli can be fixed to another position of the probe by being shifted from an original position thereof such that the shifted stylus can be contacted with another predetermined point on the printed wiring board.
16. The probe unit according to claim 11,
wherein the turn disk and the turn device are moved together by the moving device; and
wherein the turn device comprises:
a motor causing a turning driving force;
a belt transmitting the turning driving force;
a pulley being connected to the turn disk and receiving the turning driving force from the belt such that the turn disk can be turned around the turn center; and
a turn main body supporting the pulley rotatably with a bearing.
17. The probe unit according to claim 16,
wherein the moving device comprises:
a second motor causing a second turning driving force;
a second belt transmitting the second turning driving force;
a ball screw having a second pulley receiving the second turning driving force from the second belt; and
a mount member on which the turn main body is mounted.
18. An impedance measuring device for a printed wiring board, comprising the probe unit of claim 11, the measuring device further comprising:
a probe unit moving device for moving the probe unit substantially parallel to a measurement face of the printed wiring board; and
a board holding device for holding the printed wiring board to be measured;
wherein the probe unit moving device comprises:
an X-rail guiding the probe unit in an X-axis direction;
an X-driving device moving the probe unit along the X-rail;
a Y-rail guiding the probe unit in a Y-axis direction;
a Y-driving device moving the probe unit along the Y-rail; and
a control unit controlling the turn device, the moving device, X-driving device, and the Y-driving device.
19. The impedance measuring device according to claim 18,
wherein the turn disk comprises a spinning device turning the probe from the first angle to the second angle in a substantially continuous manner; and
wherein the spinning device comprises:
a pivot axis of the connecting portion, around which the probe is turned;
a probe spinning device for turning the probe around the pivot axis; and
a lock notch securing a turning position of the probe; and
wherein the control unit integrally controls the probe spinning device.
20. A control system for a impedance measuring device for a printed wiring board, comprising:
an impedance measuring part which measure a characteristic impedance of the printed wiring board to be measured;
a main control unit controlling movement of a probe unit having a probe with a contact stylus to be contacted with a predetermined point on the printed wiring board, the probe unit comprising a probe device which changes a position of the probe; and
an input-output device receiving a signal from a sensor and controlling a relay;
wherein the main control unit controls integrally the probe device.
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. A method comprising:
storing a metadata and a cache line together in a single block of memory during an update of the cache line, the metadata associated with the cache line;
storing the metadata and another metadata together during a system shutdown operation, the other metadata associated with another cache line; and
copying the metadata and the other metadata from non-volatile storage to volatile storage during a system initialization operation.
2. The method as recited in claim 1, wherein the storing the metadata and the cache line together comprises storing the metadata and the cache line in non-volatile storage.
3. The method as recited in claim 1, wherein the storing the metadata and the other metadata together comprises storing the metadata and the other metadata in non-volatile storage.
4. The method as recited in claim 3, wherein a disk cache includes the non-volatile storage.
5. The method as recited in claim 1, wherein storing the metadata and the cache line together comprises storing the metadata with the cache line during an atomic operation.
6. The method as recited in claim 1, wherein storing the metadata with the other metadata comprises storing the metadata with the other metadata in a single block of memory.
7. The method as recited in claim 1, wherein storing the metadata with the other metadata comprises storing the metadata with the other metadata during an atomic operation.
8. The method as recited in claim 1, further comprising storing the metadata in volatile memory during the update of the cache line.
9. A method comprising:
copying a plurality of metadata, each of the plurality of metadata associated with a different cache line, from a non-volatile memory to a volatile memory during a system initialization operation;
wherein if an indication of an unexpected power down is detected, the copying the plurality of metadata comprises copying the plurality of metadata from a plurality of distributed storage locations in which each of the plurality of metadata is stored with its associated cache line; and
wherein if an indication of an expected power down is detected, the copying the plurality of metadata comprises copying the plurality of metadata from a packed storage location in which the plurality of metadata are stored in a packed format in a single storage location.
10. The method as recited in claim 9, wherein the indication of an expected power down comprises a valid integrity signature stored with the plurality of metadata stored in the packed format.
11. The method as recited in claim 9, wherein each of the plurality of distributed storage locations comprises a block of memory.
12. An apparatus comprising:
a memory controller configured to store a metadata and a cache line together in a single block of memory during an update of the cache line, the metadata associated with the cache line; and the memory controller further configured to store the metadata and another metadata together during a system shutdown operation, the other metadata associated with another cache line, the memory controller further configured to copy the metadata and the other metadata from non-volatile storage to volatile storage during a system initialization operation.
13. The apparatus as recited in claim 12, wherein to store the metadata and the cache line together the memory controller is configured to store the metadata and the cache line in non-volatile storage.
14. The apparatus as recited in claim 12, wherein to store the metadata and the other metadata together the memory controller is configured to store the metadata and the other metadata in non-volatile storage.
15. The apparatus as recited in claim 14, wherein a disk cache includes the non-volatile storage.
16. The apparatus as recited in claim 12, wherein to store the metadata and the cache line together the memory controller is configured to store the metadata with the cache line during an atomic operation.
17. The apparatus as recited in claim 12, wherein to store the metadata with the other metadata the memory controller is configured to store the metadata with the other metadata in a single block of memory.
18. The apparatus as recited in claim 12, wherein to store the metadata with the other metadata the memory controller is configured to store the metadata with the other metadata during an atomic operation.
19. The apparatus as recited in claim 12, the memory controller further configured to store the metadata in volatile memory during the update of the cache line.
20. A system comprising:
a volatile memory;
a non-volatile memory; and
a memory controller coupled to the volatile memory and the non-volatile memory, the memory controller configured to store a metadata and a cache line together during an update of the cache line, the metadata associated with the cache line; the memory controller further configured to store the metadata and another metadata together during a system shutdown operation, the other metadata associated with another cache line; and the memory controller further configured to copy the metadata and the other metadata from the non-volatile storage to the volatile storage during a system initialization operation.
21. The system as recited in claim 20, wherein to store the metadata and the cache line together the memory controller is configured to store the metadata and the cache line in the non-volatile memory.
22. The system as recited in claim 20, wherein to store the metadata and the other metadata together the memory controller is configured to store the metadata and the other metadata in the non-volatile memory.
23. The system as recited in claim 22, wherein a disk cache includes the non-volatile memory.
24. The system as recited in claim 20, wherein the memory controller is further configured to:
determine if an integrity signature is valid;
if the integrity signature is valid, copy the metadata stored in a packed format; and
if the integrity signature is invalid, copy the metadata stored in a distributed format.
25. The system as recited in claim 20, the memory controller further configured to store the metadata in volatile memory during the update of the cache line.