Signal Definition; Figure 18. Table Of Signals; Figure 19. Signal Special Definitions For Ultra Dma - IBM DTLA-305040 - Deskstar 41.1 GB Hard Drive Specifications

7.1.2 Signal definition

The pin assignments of interface signals are listed in the figure below:
PIN SIGNAL
01 RESET-
03 DD7
05 DD6
07 DD5
09 DD4
11 DD3
13 DD2
15 DD1
17 DD0
19 GND
21 DMARQ
23 DIOW-(*)
25 DIOR-(*)
27 IORDY(*)
29 DMACK-
31 INTRQ
33 DA1
35 DA0
37 CSO-
39 DASP-

Figure 18. Table of signals

Notes:
1. "O" designates an output from the drive.
2. "I" designates an input to the drive.
3. "I/O" designates an input/output common.
4. "OC" designates open-collector or open-drain output.
5. The signal lines marked with (*) are redefined during the Ultra DMA protocol to provide special
functions. These lines change from the conventional to special definitions at the moment the Host
decides to allow a DMA burst if the Ultra DMA transfer mode was previously chosen via SetFeatures.
The Drive becomes aware of this change upon assertion of the DMACK- line. These lines revert back
to their original definitions upon the deassertion of DMACK- at the termination of the DMA burst.
6. (**) complies with ATA-2.
Write Operation
Read Operation

Figure 19. Signal special definitions for Ultra DMA

I/O Type PIN
I TTL 02
I/O 3-state 04
I/O 3-state 06
I/O 3-state 08
I/O 3-state 10
I/O 3-state 12
I/O 3-state 14
I/O 3-state 16
I/O 3-state 18
(20)
O 3-state 22
I TTL 24
I TTL 26
O 3-state 28
I TTL 30
O 3-state 32
I TTL 34
I TTL 36
I TTL 38
I/O OC 40
Special Definition
(for Ultra DMA)
DDMARDY-
HSTROBE
STOP
HDMARDY-
DSTROBE
STOP
Deskstar 40GV & 75GXP hard disk drive specifications
SIGNAL I/O
GND
DD8 I/O
DD9 I/O
DD10 I/O
DD11 I/O
DD12 I/O
DD13 I/O
DD14 I/O
DD15 I/O
key
GND
GND
GND
CSEL I
GND
IOCS16-(**) O
PDIAG- I/O
DA2 I
CS1- I
GND
Conventional Definition
IORDY
DIOR-
DIOW-
DIOR-
IORDY
DIOW-
24
Type
3-state
3-state
3-state
3-state
3-state
3-state
3-state
3-state
TTL
OC
OC
TTL
TTL