How many devices can PATA (Parallel Advanced Technology Attachment) support per cable?

PATA (Parallel Advanced Technology Attachment) can support two devices per cable. This is a fundamental characteristic of the PATA interface, which allows for the connection of both a master and a slave device on a single ribbon cable.

The master device is typically the primary hard drive, while the slave device may be another hard drive or other compatible PATA devices such as CD-ROM drives. The PATA standard employs a 40-pin connector and allows the identification of each device through specific jumper settings that determine whether each device operates in master, slave, or sometimes cable select mode.

This capability to connect two devices on one cable is one of the reasons PATA was widely used during its time in the industry before being mostly replaced by SATA (Serial Advanced Technology Attachment) technology, which supports only one device per cable but offers higher data transfer speeds and other advantages.