Patents by Inventor Siamack Nemazie

Siamack Nemazie has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6025966
    Abstract: A defect management system for use in a data storage system. The defect management system generates a track defect list comprising a sector defect record for each of a set of defective sectors in a track of a media surface. A sector defect record includes defect management information for each of the defective sectors. The defect management information may be generated according to one of several defect management schemes. The apparatus of the present invention stores the track defect list in a buffer or sector headers. The apparatus of the present invention maps a physical sector number to a logical sector number using the track defect list. If the track defect list is stored in sector headers, the present invention may use a ping-pong FIFO for processing the track defect list.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: February 15, 2000
    Assignee: Cirrus Logic, Inc.
    Inventors: Siamack Nemazie, John Schadegg
  • Patent number: 5864568
    Abstract: In storage subsystems such as winchester disk, blocks of sequential data corresponding to sectors are concurrently accessed by the disk and the host. Semiconductor memory devices for storing block data are often utilized as storage location for sectors of data read or written to the disk and the host. Application of a semiconductor memory which increases the effective transfer rate of the system is highly desirable particularly in disk storage systems. A semiconductor memory for use in disk storage applications where information is transferred in blocks of data is hereby disclosed. Specifically, the memory includes a main memory configured as a random access memory array having rows and columns, each row having a plurality of n-bit words, a secondary memory having a data register file, first and second parallel-by-bit interfaces and a transferring circuit for transferring data between the main and secondary memories.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: January 26, 1999
    Assignee: Cirrus Logic, Inc.
    Inventor: Siamack Nemazie
  • Patent number: 5768043
    Abstract: A table driven method and apparatus for automatic split field processing in a disk drive system stores data representing the split fields after each servo mark of a frame. Each track of the disk drive system is divided up into frames or groups of sectors or equivalently servo marks, each frame comprising a predetermined number N of sectors and a predetermined number M of servo marks. Beginning from the INDEX mark, after every N sectors or equivalently M servo marks, the next sector must start after the next servo mark. The value N is a constant within each zone on a disk but can vary from zone to zone as the storage density changes. The information for each servo mark within a frame is stored in a frame table in the buffer memory. A starting address pointer and an ending address pointer are used to keep track of the starting and ending addresses, respectively, of the frame table. An address pointer is used to point to the current entry of interest in the frame table.
    Type: Grant
    Filed: October 26, 1995
    Date of Patent: June 16, 1998
    Assignee: Cirrus Logic, Inc.
    Inventors: Siamack Nemazie, Son H. Ho
  • Patent number: 5696775
    Abstract: A method and apparatus for detecting the transfer of a wrong sector uses the LBA to ensure that a correct sector is transferred. The LBA may be appended to the sector data during a write operation and verified during a read operation. Preferably, the LBA is embedded into the CRC block during a write operation and used to detect the transfer of a wrong sector during a read operation. The LBA may be embedded within the CRC, before or after it is transmitted to a CRC Generator/Checker, by Exclusive-ORing the sector data or CRC data with the LBA. During a read operation, the incoming CRC is Exclusive-ORed with the expected LBA of the sector being read, thereby eliminating the LBA from the CRC data. The CRC data is then checked by the CRC Generator/Checker and an error is signalled if the CRC data does not match. Using the method and apparatus of the present invention, the LBA may also be embedded in the CRC during format and minimal latency operations.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: December 9, 1997
    Assignee: Cirrus Logic, Inc.
    Inventors: Siamack Nemazie, Son H. Ho, Ronald M. Yamada, Sunil Bhaskar Chaudhari, Christopher Paul Zook
  • Patent number: 5523979
    Abstract: A semiconductor memory device is disclosed including a main memory configured as a dynamic random access memory array having rows and columns, combined with a secondary memory having a data register file, a transferring circuit for allowing transfer of data between the main memory and secondary memory, a first parallel-by-bit interface for random accesses to the main memory and a second parallel-by-bit interface for access to the seconday memory. Concurrent and independent accesses of the main and secondary memories is achieved while maintaining the integrity of data. Further included in the secondary memory is a data register file and a corresponding mask register file wherein the latter achieves selection of any combination of words in a row of the secondary memory for the purposes of transferring the same to the main memory.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: June 4, 1996
    Assignee: Cirrus Logic, Inc.
    Inventor: Siamack Nemazie
  • Patent number: 5485595
    Abstract: A semiconductor mass storage device can be substituted for a rotating hard disk. The device avoid an erase cycle each time information stored in the mass storage is changed. Erase cycles are avoided by programming an altered data file into an empty mass storage block rather than over itself as a hard disk would. Periodically, the mass storage will need to be cleaned up. Secondly, a circuit and method are provided for evenly using all blocks in the mass storage. These advantages are achieved through the use of several flags, a map to correlate a logical address of a block to a physical address of that block and a count register for each block. In particular, flags are provided for defective blocks, used blocks, old versions of a block, a count to determine the number of times a block has been erased and written and an erase inhibit flag. Reading is performed by providing the logical block address to the memory storage. The system sequentially compares the stored logical block addresses until it finds a match.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: January 16, 1996
    Assignee: Cirrus Logic, Inc.
    Inventors: Mahmud Assar, Petro Estakhri, Siamack Nemazie, Mahmood Mozaffari
  • Patent number: 5479638
    Abstract: A semiconductor mass storage device can be substituted for a rotating hard disk. The device avoids an erase cycle each time information stored in the mass storage is changed. (The erase cycle is understood to include, fully programming the block to be erased, and then erasing the block.) Erase cycles are avoided by programming an altered data file into an empty mass storage block rather than over itself as a hard disk would. Periodically, the mass storage will need to be cleaned up. Secondly, a circuit for evenly using all blocks in the mass storage is provided. These advantages are achieved through the use of several flags, a map to directly correlate a logical address of a block to a physical address of that block and a count register for each block. In particular, flags are provided for defective blocks, used blocks, old version of a block, a count to determine the number of times a block has been erased and written and erase inhibit.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: December 26, 1995
    Assignee: Cirrus Logic, Inc.
    Inventors: Mahmud Assar, Siamack Nemazie, Petro Estakhri
  • Patent number: 5455721
    Abstract: A method and apparatus for automatic sector pulse generation and split field calculation in disk drives without the use of tables improves the seek latency of a disk drive system because it does not have to wait for the INDEX mark or the beginning of a frame, before beginning an operation it has been instructed to perform. The system can be designed to start from any point on the disk and begin calculations as if it were starting from the INDEX mark or the beginning of a frame. The calculations performed for each servo mark calculate the number of sectors and split fields which can be stored between servo marks on the disk. Multiple calculations can be performed between two servo marks. A counter is used to keep track of the number of servo marks for which the system has performed calculations. This counter is compared to the number of the last previously detected servo mark.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: October 3, 1995
    Assignee: Cirrus Logic, Inc.
    Inventors: Siamack Nemazie, Petro Estakhri, John Schadegg
  • Patent number: 5388083
    Abstract: A semiconductor mass storage system and architecture can be substituted for a rotating hard disk. The system and architecture avoid an erase cycle each time information stored in the mass storage is changed. (The erase cycle is understood to include, fully programming the block to be erased, and then erasing the block.) Erase cycles are avoided by programming an altered data file into an empty mass storage block rather than over itself as hard disk would. Periodically, the mass storage will need to be cleaned up. Secondly, all blocks in the mass storage are used evenly. These advantages are achieved through the use of several flags, a map to correlate a logical address of a block to a physical address of that block and a count register for each block. In particular, flags are provided for defective blocks, used blocks, old version of a block, a count to determine the number of times a block has been erased and written and erase inhibit flag.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: February 7, 1995
    Assignee: Cirrus Logic, Inc.
    Inventors: Mahmud Assar, Siamack Nemazie, Petro Estakhri
  • Patent number: 5317505
    Abstract: The user controller for a video game has a set of auxiliary buttons from which a user may input requests to store, request and execute stored sequences of user playing button settings. The auxiliary buttons are programmable and could be assigned to arbitrary special moves matching the needs of different games or of different stages of one game. The controller can store any arbitrary sequence of user play button settings to relieve the user from having to repeat inputting the sequence. The user may also add to a stored sequence during execution on the fly to form a merged sequence which may be stored. The controller also permits the user to override a stored sequence during execution. Special moves possible include a sequence of fast paced reproductions of predetermined moves. The controller also disregards unintended idle settings to provide more realistic rendition of stored sequences.
    Type: Grant
    Filed: December 19, 1990
    Date of Patent: May 31, 1994
    Inventors: Raznik Karabed, Siamack Nemazie, Edmond Sardariani