Memory system
A memory system includes a semiconductor memory and a controller. The controller is configured to perform a read operation on the semiconductor memory in response to a read instruction received from a host. In response to the read instruction that includes a first logical address, the controller converts the first logical address into a first physical address, and issues a read command and a second physical address different from the first physical address, to the semiconductor memory.
1. A memory system comprising:
a semiconductor memory; and
a controller configured to perform a read operation on the semiconductor memory in response to a read instruction received from a host, wherein
in response to the read instruction that includes a first logical address, the controller converts the first logical address into a first physical address, and issues a read command and a second physical address different from the first physical address, to the semiconductor memory, wherein
the semiconductor memory includes a plurality of memory cells associated with a row address and a column address, and decodes a physical address received from the controller into a row address and a column address, and
the row addresses corresponding to the first and second physical addresses are the same, and the column address corresponding to the first physical address is different from the column address corresponding to the second physical address.
2. The memory system according to claim 1 , wherein
the controller determines the second physical address from the first physical address by shifting the column address corresponding to the first physical address.
3. The memory system according to claim 1 , wherein
the semiconductor memory includes a memory cell array including the plurality of memory cells, and is configured to read data in a unit of a page from the memory cell array when the read command and the second physical address are received from the controller and transfer the read data in units less than a size of the page to the controller in order, starting from a column address corresponding to the second physical address and then incrementing the column address each time a first clock is received from the controller after the read command.
4. The memory system according to claim 3 ,
wherein the semiconductor memory is configured to transfer data corresponding to a top column address to the controller when the first clock is further received after the column address has reached the last column address.
5. The memory system according to claim 4 , wherein
the semiconductor memory transmits the read data together with a second clock to the controller, and
the controller includes a receiving circuit that receives the second clock and the read data, and a buffer circuit into which the read data received during a first plurality of cycles of the second clock are not stored and the read data received after the first plurality of cycles of the second clock are stored.
6. The memory system according to claim 5 ,
wherein the number of cycles in the first plurality of cycles of the second clock corresponds to a difference between the column address corresponding to the first physical address and the column address corresponding to the second physical address.
7. A memory system comprising:
a semiconductor memory; and
a controller configured to perform a read operation on the semiconductor memory in response to a read instruction received from a host, wherein
when the controller issues a read command to the semiconductor memory for first data immediately after the first data is written into the semiconductor memory, second data different from the first data is returned from the semiconductor memory, the second data including third data and first data following the third data, and
the semiconductor memory includes a plurality of memory cells associated with a row address and a column address, and a write operation is executed on the semiconductor memory responsive to a host write instruction including a first logical address, beginning at a first column address, and a read operation is executed on the semiconductor memory responsive to a host read instruction including the first logical address beginning at a second column address that is different from the first column address.
8. The memory system according to claim 7 ,
wherein the controller discards the third data.
9. The memory system according to claim 7 , wherein
the semiconductor memory is configured to read data in a unit of a page from the memory cell array when a read command is received from the controller and to write data in the unit of the page into the memory cell array when a write command is received from the controller, and
the controller includes a table storing a mapping of logical addresses to physical addresses, including a mapping from the first logical address to a first physical address that specifies the first column address, the table not including any mapping from the first logical address to a second physical address that specifies the second column address.
10. The memory system according to claim 9 , wherein
at the time of the write operation, the controller converts the first logical address into the first physical address based on the table and issues a write command to the semiconductor memory to write data into an area corresponding to the first physical address, and
at the time of the read operation, the controller converts the first logical address into the first physical address based on the table, further converts the first physical address into a second physical address so that the column address is shifted, and issues a read command to the semiconductor memory to read data from an area corresponding to the second physical address.
11. A method of performing a read operation on a semiconductor memory, comprising:
in response to a read instruction received from a host, converting a first logical address included in the read instruction into a first physical address, and issuing a read command and a second physical address different from the first physical address, to the semiconductor memory; and
partially buffering data returned from the semiconductor memory in response to the read command and the second physical address, wherein
the data are returned over a plurality of clock cycles and the data returned during a first plurality of clock cycles are not buffered and the data returned after the first plurality of cycles are buffered.
12. The method according to claim 11 , wherein
the semiconductor memory includes a plurality of memory cells associated with a row address and a column address, and decodes a physical address into a row address and a column address, and
the row addresses corresponding to the first and second physical addresses are the same, and the column address corresponding to the first physical address is different from the column address corresponding to the second physical address.
13. The method according to claim 12 , further comprising:
determining the second physical address from the first physical address by shifting the column address corresponding to the first physical address.
14. The method according to claim 11 , wherein
wherein the semiconductor memory includes a memory cell array including a plurality of memory cells, and is configured to read data in a unit of a page from the memory cell array in response to a read command and a physical address that are issued thereto and return the read data in units less than a size of the page in order, starting from a column address corresponding to the physical address and then incrementing the column address each time a first clock is received after the read command.
15. The method according to claim 14 ,
wherein the semiconductor memory is configured to return data corresponding to a top column address when the first clock is further received after the column address has reached the last column address.
16. The method according to claim 11 ,
wherein the number of cycles in the first plurality of cycles corresponds to a difference between the column address corresponding to the first physical address and the column address corresponding to the second physical address.
17. A memory system comprising:
a semiconductor memory including a plurality of memory cells associated with a row address and a column address; and
a controller configured to, in response to a read request received from a host, the read request including a first logical address, convert the first logical address into a first physical address, and read data from a second physical address of the semiconductor memory, wherein
the row addresses corresponding to the first and second physical addresses are the same, and the column address corresponding to the first physical address is different from the column address corresponding to the second physical address.
18. The memory system according to claim 17 , wherein the controller is further configured to discard a part of the read data that does not correspond to the first physical address.
19. The memory system according to claim 17 , wherein the controller is further configured to not transmit to the host, a part of the read data that does not correspond to the first physical address.
20. The memory system according to claim 17 , wherein the controller is further configured to:
discard a first part of the read data that does not correspond to the first physical address; and
perform an error correction on a second part of the read data that corresponds to the first physical address.
21. The memory system according to claim 20 , wherein the controller is further configured to not transmit to the host, the first part of the read data that does not correspond to the first physical address.
22. The memory system according to claim 20 , wherein the controller is further configured to transmit to the host, the second part of the read data that corresponds to the first physical address.
23. A method of performing a read operation on a semiconductor memory, the semiconductor memory including a plurality of memory cells associated with a row address and a column address, said method comprising:
in response to a read request received from a host, the read request including a first logical address, converting the first logical address into a first physical address, and reading data from a second physical address of the semiconductor memory, wherein
the row addresses corresponding to the first and second physical addresses are the same, and the column address corresponding to the first physical address is different from the column address corresponding to the second physical address.
24. The method according to claim 23 , further comprising:
discarding a part of the read data that does not correspond to the first physical address.
25. The method according to claim 23 , further comprising:
not transmitting to the host, a part of the read data that does not correspond to the first physical address.
26. The method according to claim 23 , further comprising:
discarding a first part of the read data that does not correspond to the first physical address; and
performing an error correction on a second part of the read data that corresponds to the first physical address.
27. The method according to claim 26 , further comprising:
not transmitting to the host, the first part of the read data that does not correspond to the first physical address.
28. The method according to claim 26 , further comprising:
transmitting to the host, the second part of the read data that corresponds to the first physical address.