A hard disk drive controller includes a buffer block temporarily storing recording data received from a host or reproduced data to be output to the host. A formatter outputs the recording data or the reproduced data and outputs a first control signal and a second control signal based on error information of partial data sectors included in a data sector corresponding to the recording data or the reproduced data. An error correction code block encodes and outputs data corresponding to partial data sectors having no errors in the received recording data based on the first control signal received from the formatter during a write operation and decodes data corresponding to partial data sectors having no errors in the received reproduced data based on the first control signal and outputs the decoded data in response to the second control signal during a read operation.