1. A method comprising:
designating a first set of logical units in an erase block as units available for storing data;
designating a second set of logical units in the erase block as overhead units;
changing the designation of one or more of the second set of logical units from overhead units to units available for storing data in response to one or more of the first set of logical units being marked as dirty or invalid; and
changing the designation of the one or more of the first set of logical units marked as dirty or invalid from units available for storing data to overhead units.
2. The method of claim 1 wherein the logical units in the first set and the logical units in the second set are each equal to a predetermined fixed size.
3. The method of claim 1 wherein the erase block corresponds to a group of logical units in a flash memory device to be erased as a group.
4. The method of claim 2 wherein the flash memory device comprises a NOR flash memory device.
5. The method of claim 1 further comprising:
determining a number of logical units marked as dirty or invalid in the erase block;
determining whether the number of logical units marked as dirty or invalid exceeds a pre-selected threshold value;
generating an indication of zero logical units marked as dirty or invalid if the number of logical units marked as dirty or invalid is less then, or equal to, the threshold value; and
generating an indication of logical units marked as dirty or invalid as the number of logical units marked as dirty or invalid minus the threshold value.
6. The method of claim 4 wherein the threshold value is equal to the number of logical units in the second set of logical units.
7. The method of claim 4 further comprising performing a reclamation operation on the erase block if the indication of logical units marked as dirty or invalid exceeds a reclamation threshold value.
8. An apparatus comprising:
an array of memory cells grouped as multiple erase blocks, each erase block having multiple logical units;
a control agent coupled with the array of memory cells to control a state corresponding to each of the multiple logical units, wherein the control unit is configured to designate a first set of logical units in a selected erase block as units available for storing data, designate a second set of logical units in the erase block as overhead units, change the designation of one or more of the second set of logical units from overhead units to units available for storing data in response to one or more of the first set of logical units being marked as dirty or invalid, and change the designation of the one or more of the first set of logical units marked as dirty or invalid from units available for storing data to overhead units.
9. The apparatus of claim 8 wherein the logical units in the first set and the logical units in the second set are each equal to a predetermined fixed size.
10. The apparatus of claim 8 wherein the control agent comprises a file system driver.
11. The apparatus of claim 8 wherein the control agent comprises a memory control agent within a flash memory device.
12. The apparatus of claim 8 wherein the array of memory cells comprise NOR flash memory cells.
13. The apparatus of claim 8 wherein the control agent is further configured to determine a number of logical units marked as dirty or invalid in the erase block, determine whether the number of logical units marked as dirty or invalid equals or exceeds a pre-selected threshold value, generate an indication of zero logical units marked as dirty or invalid if the number of logical units marked as dirty or invalid is less then or equal to the threshold value, and generate an indication of logical units marked as dirty or invalid as the number of logical units marked as dirty or invalid minus the threshold value.
14. The apparatus of claim 13 wherein the threshold value is equal to the number of logical units in the second set of logical units.
15. The apparatus of claim 13 wherein the control agent is further configured to perform a reclamation operation on the erase block if the indication of logical units marked as dirty or invalid is equal to or exceeds a reclamation threshold value.
16. A system comprising:
a substantially omni-directional antenna;
a processor coupled with the antenna;
an array of memory cells grouped as multiple erase blocks, each erase block having multiple logical units;
a control agent coupled with the array of memory cells and the processor to control a state corresponding to each of the multiple logical units, wherein the control unit is configured to designate a first set of logical units in a selected erase block as units available for storing data, designate a second set of logical units in the erase block as overhead units, change the designation of one or more of the second set of logical units from overhead units to units available for storing data in response to one or more of the first set of logical units being marked as dirty or invalid, and change the designation of the one or more of the first set of logical units marked as dirty or invalid from units available for storing data to overhead units.
17. The system of claim 16 wherein the logical units in the first set and the logical units in the second set are each equal to a predetermined fixed size.
18. The system of claim 16 wherein the control agent comprises a file system driver.
19. The system of claim 16 wherein the control agent comprises a memory control agent within a flash memory device.
20. The system of claim 16 wherein the array of memory cells comprise NOR flash memory cells.
21. The system of claim 16 wherein the control agent is further configured to determine a number of logical units marked as dirty or invalid in the erase block, determine whether the number of logical units marked as dirty or invalid equals or exceeds a pre-selected threshold value, generate an indication of zero logical units marked as dirty or invalid if the number of logical units marked as dirty or invalid is less then or equal to the threshold value, and generate an indication of logical units marked as dirty or invalid as the number of logical units marked as dirty or invalid minus the threshold value.
22. The system of claim 16 wherein the threshold value is equal to the number of logical units in the second set of logical units.
23. The system of claim 16 wherein the control agent is further configured to perform a reclamation operation on the erase block if the indication of logical units marked as dirty or invalid is equal to or exceeds a reclamation threshold value.
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 angular velocity detection device comprising:
an outer frame including a fixed portion and an outer beam portion connected to the fixed portion;
a sensing part surrounded by the outer frame with a first slit therebetween; and
a joint connecting the outer frame to the sensing part,
wherein the sensing part includes:
an inner beam portion having a hollow region inside, and being square-shaped when viewed from above;
a flexible portion disposed in the hollow region of the inner beam portion, and connected to an inner edge of the inner beam portion; and
a detector disposed in the flexible portion, wherein
the first slit is formed to surround the sensing part excluding the joint,
the flexible portion includes:
a central beam portion connecting opposite sides of the inner beam portion together, and being in parallel with the outer beam portion;
a first arm disposed inside the inner beam portion, and connected to the central beam portion;
a second arm disposed inside the inner beam portion, connected to the central beam portion, disposed on a same side as the first arm with respect to the central beam portion, and formed line-symmetrically with respect to the first arm;
a third arm disposed inside the inner beam portion, connected to the central beam portion, disposed on an opposite side of the first arm with respect to the central beam portion, and formed line-symmetrically with respect to the first arm; and
a fourth arm disposed inside the inner beam portion, connected to the central beam portion, disposed on a same side as the third arm with respect to the central beam portion, and formed line-symmetrically with respect to the third arm,
wherein the detector is one of detectors and the detectors are disposed on the first arm, the second arm, the third arm, and the fourth arm respectively,
the detectors are disposed symmetrically with respect to the Y axis and the X axis, and
the inner beam portion has a second slit formed centrally within the inner beam portion adjacent a corner of the inner beam portion.
2. The angular velocity detection device of claim 1, wherein
the first arm, the second arm, the third arm, and the fourth arm are provided thereon with drivers respectively.
3. The angular velocity detection device of claim 1, wherein
the fixed portion is one of fixed portions and the fixed portions are formed as an opposing pair with the outer beam portions therebetween;
the outer beam portion is one of outer beam portions and the outer beam portions are formed as an opposing pair with the fixed portions therebetween; and
the joint is one of joints and the joints are formed at two places where the outer beam portions and the inner beam portion are parallel to each other.
4. An angular velocity detection device comprising:
an outer frame including a fixed portion and an outer beam portion connected to the fixed portion;
a sensing part surrounded by the outer frame with a first slit therebetween; and
a joint connecting the outer frame to the sensing part, wherein the sensing part includes:
an inner beam portion having a hollow region inside, and being square-shaped when viewed from above;
a flexible portion disposed in the hollow region of the inner beam portion, and connected to an inner edge of the inner beam portion; and
a detector disposed in the flexible portion, wherein
the first slit is formed to surround the sensing part excluding the joint, wherein the fixed portion is one of fixed portions and the fixed portions are formed as an opposing pair with the outer beam portions therebetween;
the outer beam portion is one of outer beam portions and the outer beam portions are formed as an opposing pair with the fixed portions therebetween; and
the joint is one of joints and the joints are formed at two places where the outer beam portions and the inner beam portion are parallel to each other, wherein
where X, Y, and Z axes are orthogonal to each other, the angular velocity detection device extends in an X-Y plane formed of the X axis and the Y axis; and
the detector is an angular velocity detector around the Z axis, and wherein
the angular velocity detection device further comprises an angular velocity detector around the X axis formed on a side, which is parallel to the fixed portions, of the inner beam portion, and the inner beam portion has a second slit formed centrally within the inner beam portion and adjacent to the angular velocity detector around the X axis.
5. The angular velocity detection device of claim 4, wherein
the second slit is formed closer to a corner of the inner beam portion than the angular velocity detector around the X axis.
6. The angular velocity detection device of claim 5, wherein
the second slit is a right trapezoid when viewed from the above, the second slit having an upper base, a lower base longer than the upper base, and an oblique side connecting the upper base to the lower base;
the lower base is disposed on an outer side of the inner beam portion in a width direction; and
the oblique side is disposed closer to the corner of the inner beam portion.
7. An angular velocity detection device comprising:
an outer frame including a fixed portion and an outer beam portion connected to the fixed portion;
a sensing part surrounded by the outer frame with a first slit therebetween; and
a joint connecting the outer frame to the sensing part, wherein the sensing part includes:
an inner beam portion having a hollow region inside, and being square-shaped when viewed from above;
a flexible portion disposed in the hollow region of the inner beam portion, and connected to an inner edge of the inner beam portion; and
a detector disposed in the flexible portion, wherein
the first slit is formed to surround the sensing part excluding the joint, wherein the fixed portion is one of fixed portions and the fixed portions are formed as an opposing pair with the outer beam portions therebetween;
the outer beam portion is one of outer beam portions and the outer beam portions are formed as an opposing pair with the fixed portions therebetween; and
the joint is one of joints and the joints are formed at two places where the outer beam portions and the inner beam portion are parallel to each other, wherein
where X, Y, and Z axes are orthogonal to each other, the angular velocity detection device extends in an X-Y plane formed of the X axis and the Y axis; and
the detector is an angular velocity detector around the Z axis, and wherein
the angular velocity detection device further comprises an angular velocity detector around the Y axis disposed on a side, which is parallel to the outer beam portions, of the inner beam portion, and the inner beam portion has a second slit formed centrally within the inner beam portion and adjacent to the angular velocity detector around the Y axis.
8. The angular velocity detection device of claim 7, wherein
the second slit is formed closer to a corner of the inner beam portion than the angular velocity detector around the Y axis.
9. The angular velocity detection device of claim 8, wherein
the second slit is a right trapezoid when viewed from the above, the second slit having an upper base, a lower base longer than the upper base, and an oblique side connecting the upper base to the lower base;
the lower base is disposed on an outer side of the inner beam portion in a width direction; and
the oblique side is disposed closer to the corner of the inner beam portion.
10. An angular velocity sensor comprising:
the angular velocity detection device of claim 1; and
a detecting circuit for processing signals supplied from the detectors of the angular velocity detection device.