Seagate U4 ST36421A - Manual (Page 29)

U4 Family Product Manual, Rev. D 21
3.0 ATA interface
These drives use the industry-standard ATA task file interface that
supports 16-bit data transfers. It supports ATA programmed input/output
(PIO) modes 0–4; multiword DMA modes 0–2, and Ultra DMA modes
0–4. The drive also supports the use of the IORDY signal to provide
reliable high-speed data transfers.
You can use a daisy-chain cable to connect two drives to a single AT
host bus. For detailed information about the ATA interface, refer to the
draft of
AT Attachment with Packet Interface Extension (ATA/ATAPI-4),
NCITS T13 1153D, subsequently referred to as the Draft ATA-4 Stan-
dard.
3.1 ATA interface signals and connector pins
Figure 4 on page 22 summarizes the signals on the ATA interface
connector that the drive supports. For a detailed description of these
signals, refer to the
Draft ATA-4 Standard.