Hitachi CinemaStar P7K500 Specifications page 27

CSEL (Cable Select) (Optional)
The drive is configured as either Device 0 or 1 depending upon the value of CSEL.
• If CSEL is grounded, the device address is 0.
• If CSEL is open, the device address is 1.
KEY Pin position 20 has no connection pin. It is recommended to close the respective position of
the cable connector in order to avoid incorrect insertion by mistake.
IORDY This signal is negated to extend the host transfer cycle when a drive is not ready to respond
to a data transfer request and may be negated when the host transfer cycle is less than 240
ns for PIO data transfer. This signal is an open-drain output with 24 mA sink capability and
an external resistor is needed to pull up this line to 5 volts.
DMACK- This signal shall be used by the host in response to DMARQ to either acknowledge that data
has been accepted or that data is available.
This signal is internally pulled up to 3.3 V through a 15 KΩ resistor. The tolerance of the
resistor value is –50% to +100%.
DMARQ This signal, used for DMA data transfers between host and drive, shall be asserted by the
drive when it is ready to transfer data to or from the host. The direction of data transfer is
controlled by DIOR- and DIOW-. This signal is used on a handshake manner with DMACK-.
This signal is a 3-state line with 24mA sink capability and internally pulled down to GND
through 10 KΩ resistor.
HDMARDY- (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
HDMARDY- is a flow control signal for Ultra DMA data in bursts. This signal is held asserted
by the host to indicate to the device that the host is ready to receive Ultra DMA data in
transfers. The host may negate HDMARDY- to pause an Ultra DMA data in transfer.
HSTROBE (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
HSTROBE is the data out strobe signal from the host for an Ultra DMA data out transfer.
Both the rising and falling edge of HSTROBE latch the data from DD(15:0) into the device.
The host may stop toggling HSTROBE to pause an Ultra DMA data out transfer.
STOP (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
STOP shall be asserted by the host prior to initiation of an Ultra DMA burst. STOP shall be
negated by the host before data is transferred in an Ultra DMA burst. Assertion of STOP by
the host during or after data transfer in an Ultra DMA mode signals the termination of the
burst.
DDMARDY- (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
DDMARDY- is a flow control signal for Ultra DMA data out bursts. This signal is held
asserted by the device to indicate to the host that the device is ready to receive Ultra DMA
data out transfers. The device may negate DDMARDY- to pause an Ultra DMA data out
transfer.
DSTROBE (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
DSTROBE is the data in strobe signal from the device for an Ultra DMA data in transfer.
Both the rising and falling edge of DSTROBE latch the data from DD(15:0) into the host. The
device may stop toggling DSTROBE to pause an Ultra DMA data in transfer.
Device Termination
The termination resistors on the device side are implemented on the drive side as follows:
• 33 Ω for DD0 thru DD15, DMARQ, INTRQ
• 82 Ω for CS0-, CS1-, DA0, DA1, DA2, DIOR-, DIOW-, DMACK-
• 22 Ω for IORDY
HITACHI Deskstar & CinemaStar P7K500 Hard Disk Drive specification (Rev 1.1)
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