IBM DTTA-351010 - Deskstar 10.1 GB Hard Drive Specifications page 30

00h. Device 0 may be unable to accept commands until it has finished its reset procedure
and is ready ( D R D Y = 1 ) .
CSEL (Cable Select) (Optional)
The drive is configured as either Device 0 or 1 depending upon the value of CSEL.
If CSEL is grounded then the device address is 0.
If CSEL is open then 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
nsec for PIO data transfer. This signal is an open-drain output with 24 mA sink capability
and an external resistor is needed to pull this line to 5 volts.
-DMACK This signal shall be used by the host in response to D M A R Q to either acknowledge that
data has been accepted, or that data is available.
This signal is internally pulled-up to 5Volt through 15 K ohm resistor and the tolerance of
the resistor value is -50% to + 1 0 0 % .
DMARQ This signal, used for D M A 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 -HIOR and -HIOW. 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 G N D through 10 k
-HDMARDY (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
-HDMARDY is a flow control signal for Ultra D M A data in bursts. This signal is held
asserted by the host to indicate to the device that the host is ready to receive Ultra D M A
data in transfers. The host may negate -HDMARDY to pause an Ultra D M A data in
transfer.
HSTROBE (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
HSTROBE is the data out strobe signal from the host for an Ultra D M A 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 D M A data out transfer.
STOP (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
STOP shall be asserted by the host prior to initiation of an Ultra D M A burst. STOP shall
be negated by the host before data is transferred in an Ultra D M A burst. Assertion of STOP
by the host during or after data transfer in an Ultra D M A mode signals the termination of
the burst.
-DDMARDY (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
-DDMARDY is a flow control signal for Ultra D M A data out bursts. This signal is held
asserted by the device to indicate to the host that the device is ready to receive Ultra D M A
data out transfers. The device may negate -DDMARDY to pause an Uptra D M A data out
transfer.
22
O E M Specifications for DTTA-3xxxxx
resistor.