Storage system and operating method of the same

A storage system comprising:

• a storage controller;
• and
• a plurality of non-volatile memory devices connected to the storage controller with a first signal line for transmitting a command and an address and a second signal line for transmitting data,
• wherein the first signal line and the second signal line are separated from each other, and
• wherein the storage controller is configured to:
• transmit an access command as the command to a first non-volatile memory device of the plurality of non-volatile memory devices using the first signal line;
• receive a logic level of a ready/busy signal using a R/B pin of the first non-volatile memory device during a time when an operation corresponding to the access command is performed on the first non-volatile memory device;
• check a status of the first non-volatile memory device on the first signal line;
• perform, in response to the logic level of the ready/busy signal representing a busy status, a ZQ calibration on the first non-volatile memory device;
• and
• check, after the performing of the ZQ calibration, the status of the first non-volatile memory device.

A storage system comprising:

• a plurality of non-volatile memory devices;
• and
• a storage controller connected to the plurality of non-volatile memory devices and configured to:
• perform a first ZQ calibration on the plurality of non-volatile memory devices which are turned on,
• transmit an access command through a DQ pin each of the plurality of non-volatile memory devices,
• receive a busy status signal indicating a busy status from each of the plurality of non-volatile memory devices operating in response to the access command,
• perform a second ZQ calibration on the plurality of non-volatile memory devices, and
• check whether the second ZQ calibration is correctly performed on each of the plurality of non-volatile memory devices.