Seagate ST3400832ACE, ST3200826ACE, ST3250823ACE manual ATA interface signals and connector pins

4.0ATA 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 0–5. 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-7), NCITS T13 1410D, subsequently referred to as the Draft ATA-7 Standard.

4.1ATA interface signals and connector pins

Figure 7 summarizes the signals on the ATA interface connector that the drive supports. For a detailed descrip- tion of these signals, refer to the Draft ATA-7 Standard.

Drive pin #	Signal name					Host pin # and signal description
1			Reset–					1			Hardware Reset
2			Ground	2							Ground
3			DD7		3						Host Data Bus Bit 7
4			DD8		4						Host Data Bus Bit 8
5			DD6		5						Host Data Bus Bit 6
6			DD9		6						Host Data Bus Bit 9
7			DD5		7						Host Data Bus Bit 5
8			DD10		8						Host Data Bus Bit 10
9			DD4		9						Host Data Bus Bit 4
10			DD11		10						Host Data Bus Bit 11
11			DD3		11						Host Data Bus Bit 3
12			DD12		12						Host Data Bus Bit 12
13			DD2		13						Host Data Bus Bit 2
14			DD13		14						Host Data Bus Bit 13
15			DD1		15						Host Data Bus Bit 1
16			DD14		16						Host Data Bus Bit 14
17			DD0		17						Host Data Bus Bit 0
18			DD15		18						Device Data (15:0)
19			Ground	19							Ground
20			(removed)	20							(No Pin)
21			DMARQ						21		DMA Request
22			Ground	22							Ground
23			DIOW–						23		Device I/O Write:
			STOP								Stop Ultra DMA Burst
24			Ground	24							Ground
25			DIOR–							25	Device I/O Read:
		HDMARDY–									Host Ultra DMA Ready:
			HSTROBE								Host Ultra DMA Data Strobe
26			Ground	26							Ground
27			IORDY				27				I/O Channel Ready
		DDMARDY–									Device Ultra DMA Ready
			DSTROBE								Device Ulta DMA Data Strobe
28			CSEL							28	Cable Select
29			DMACK–							29	DMA Acknowledge
30			Ground	30							Ground

31INTRQ 31 Device Interrupt

32IOCS16– 32 Reserved

33	DA1			33	Host Address Bus Bit 1
34	PDIAG–			34	Passed Diagnostics
	CBLID–				Cable Assembly Type Identifier
35	DA0			35	Device Address (2:0)
36	DA2			36	Device Address (2:0)
37	CS0–			37	Chip Select (1:0)
38	CS1–			38	Chip Select (1:0)
39	DASP–		39		Drive Active/Slave Present
40	Ground	40			Ground

Pins 28, 34 and 39 are used for master-slave communication (details shown below).

Drive 1 (slave)

28

34

39

Drive 0 (master)

28

34

39

CSEL

PDIAG–

DASP–

Host

28

34

39

Figure 7 I/O pins and supported ATA signals

DB35 Series Product Manual, Rev. B 21