Memory device and controlling method of the same

A method of controlling a memory device comprising a memory comprising memory areas and a controller, the method comprising:

• upon receipt of write data, writing data in the memory areas while managing correspondence between addresses of the write data and memory areas which store corresponding write data, a plurality of the memory areas constituting a management unit;
• receiving a start command and, after the start command, a first write command to a first management unit to perform sequential writes to the first management unit in a sequential mode;
• and
• receiving a second write command to a second management unit, the second management unit having an address that is non-sequential with an address of the first management unit, to end the sequential mode to perform writes to the second management unit to invalidate data in the first management unit which has not been updated by writes to the first management unit and to maintain data in the second management unit which has not been updated by writes to the second management unit.

A memory system comprising a memory device and a host device connectable to the memory device, the memory device comprising:

• a memory which includes memory areas;
• and
• a controller configured to, upon receipt of write data, write data in the memory areas while managing correspondence between addresses of write data and memory areas which store corresponding write data, wherein
• a plurality of the memory areas constitutes a management unit,
• the controller is configured:
• to perform, upon receipt of a write request including a sequential write start command, a first write command to a first management unit, and write data items having serial addresses in the first management unit, sequential writes of the write data items to the first management unit in a sequential mode, no data item that has been stored in the first management unit before receipt of the write request and has not been updated by the write request being stored in the first management unit, the first write command being received after the sequential write start command without any command therebetween, and the write data items being received after the first write command;
• and
• to end, upon receipt of a second write command to a second management unit having an address that is non-sequential with an address of the first management unit in the sequential mode, the sequential mode to perform writes to the second management unit to invalidate data in the first management unit which has not been updated by writes to the first management unit and to maintain data in the second management unit which has not been updated by writes to the second management unit, and
• the host device is configured:
• to transmit to the memory device the sequential write start command and the first write command after the sequential write start command, and
• to transmit to the memory device the second write command to the second management unit.