Signal Descriptions; Figure 34. Special Signal Definitions For Ultra Dma - IBM DJSA-210 - Travelstar 10 GB Hard Drive Specifications

Write Operation
Read Operation

Figure 34. Special signal definitions for Ultra DMA

7.4 Signal descriptions

DD00–DD15
A 16-bit bi-directional data bus between the host and the HDD. The lower 8 lines, DD00-07, are used
for Register and ECC access. All 16 lines, DD00–15, are used for data transfer. These are 3-state
lines with 24 mA current sink capability.
DA00–DA02
These are addresses used to select the individual register in the HDD.
-CS0
The chip select signal generated from the Host address bus. When active, one of the Command Block
Registers [Data, Error (Features when written), Sector Count, Sector Number, Cylinder Low, Cylinder
High, Drive/Head and Status (Command when written) register] can be selected.
-CS1
The chip select signal generated from the Host address bus. When active, one of the Control Block
Registers [Alternate Status (Device Control when written) and Drive Address register] can be
selected.
-RESET
This line is used to reset the HDD. It shall be kept at a Low logic state during power up and kept High
thereafter.
-DIOW
The rising edge of this signal holds data from the data bus to a register or data register of the HDD.
-DIOR
When this signal is low it enables data from a register or data register of the drive onto the data bus.
The data on the bus shall be latched on the rising edge of -DIOR.
INTRQ
The interrupt is enabled only when the drive is selected and the host activates the -IEN bit in the
Device Control Register. Otherwise, this signal is in high impedance state regardless of the state of
the IRQ bit. The interrupt is set when the IRQ bit is set by the drive CPU. The IRQ is reset to zero by a
host read of the status register or a write to the Command Register. This signal is a 3-state line with
24 mA of sink capability.
Special Definition
(for Ultra DMA)
–DDMARDY
HSTROBE
STOP
–HDMARDY
DSTROBE
STOP
Travelstar 32GH/30GT/20GN hard disk drive specifications
43
Conventional Definition
IORDY
–DIOR
–DIOW
–DIOR
IORDY
–DIOW