Memory system, memory controller, and semiconductor memory device

A nonvolatile semiconductor memory configured to:

• receive, from a memory controller, a first command set including arithmetic operation target data and an address that designates a memory cell to store weight data;
• read the weight data from the memory cell designated by the address;
• perform an arithmetic operation based on the arithmetic operation target data and the weight data;
• and send arithmetic operation result data to the memory controller.

A memory controller configured to:

• send, to a nonvolatile semiconductor memory, a first command set including arithmetic operation target data and an address that designates a memory cell to store weight data;
• cause the nonvolatile semiconductor memory to perform an arithmetic operation using the arithmetic operation target data and the weight data;
• and
• receive the arithmetic operation target data from the nonvolatile semiconductor memory.