enhanced small device interface (ESDI)

Enhanced Small Device Interface (ESDI) is an older interface for hard disks and optical storage devices, which is based on the Seagate driver for hard disk drives.

The ESDI interface was used in PS/2 computers, among others. It had a transfer rate of up to 24 Mbit/s between storage unit and controller. The high data rate is achieved by the controller being located in the hard disk electronics. Normally, the ESDI interface operated at a data rate of 10 Mbit/s. The ESDI interface allowed a maximum of seven ESDI drives to be connected.

The ESDI interface was superseded by the EIDE interface and the SCSI interface.