Abstract: A reading method of a semiconductor memory device having a multi-level memory cell includes the steps of: reading flag data indicating whether the most significant bit (MSB) of data programmed in the multi-level memory cell is programmed or not; storing the read flag data; reading the least significant bit (LSB) of the data programmed in the multi-level memory cell, based on the read flag data; and reading the MSB of the data programmed in the multi-level memory cell based on the stored flag data.

Abstract: A semiconductor memory device includes a first plane and a second plane each configured to include a plurality of memory cells, and a data transfer circuit configured to transfer first data, stored in the memory cells of the first plane, to the second plane and transfer second data, stored in the memory cells of the second plane, to the first plane when a copyback operation is performed and to transfer the first data or the second data to an I/O circuit when a read operation is performed.

Abstract: A method of operating a memory system according to an aspect of the present disclosure includes storing first data in a memory controller; storing second data in the memory controller, wherein the second data is read from a selected page of a first memory block of a memory device; and performing a program operation for storing third data, that include the first data and the second data, in a selected page of a second memory block of the memory device.

Abstract: A test method for nonvolatile memory devices where, in one aspect of the method, a specific operation mode is selected according to a signal input through a single I/O pin in a period in which a write enable signal is inactivated. The write enable signal or a read enable signal is activated according to the selected operation mode. A plurality of signals is input through the single I/O pin in a period in which the write enable signal is activated. The plurality of signals is output through the single I/O pin in a period in which the read enable signal is activated.

Abstract: A test method for nonvolatile memory devices where, in one aspect of the method, a specific operation mode is selected according to a signal input through a single I/O pin in a period in which a write enable signal is inactivated. The write enable signal or a read enable signal is activated according to the selected operation mode. A plurality of signals is input through the single I/O pin in a period in which the write enable signal is activated. The plurality of signals is output through the single I/O pin in a period in which the read enable signal is activated.