Hitachi HTS542525K9SA00 Specifications page 39

DASP-
This is a time-multiplexed signal which indicates that a drive is active or that device 1 is present. This signal is
driven by an Open-Drain driver and internally pulled up to 5 volts through a 10 kW resistor. During a Power-On
initialization or after RESET- is negated, DASP- shall be asserted by Device 1 within 400 ms to indicate that
device 1 is present. Device 0 shall allow up to 450 ms for device 1 to assert DASP-. If device 1 is not present,
device 0 may assert DASP- to drive an LED indicator. The DASP- signal shall be negated following acceptance
of the first valid command by device 1. Anytime after negation of DASP-, either drive may assert DASP- to
indicate that a drive is active.
During Power-On initialization or after RESET- is negated, DASP- shall be asserted by Device 1 within 400 ms
to indicate that device 1 is present. Device 0 shall allow up to 450ms for device 1 to assert DASP-. If device 1 is
not present, device 0 may assert DASP- to drive a LED indicator.
DASP- shall be negated following acceptance of the first valid command by device 1. At anytime after nega-
tion of DASP-, either drive may assert DASP- to indicate that a drive is active.
PDIAG-
This signal shall be asserted by device 1 to indicate to device 0 that it has completed the diagnostics. This line is
pulled up to 5 volts in the drive through a 10 kΩ resistor.
Following a Power On Reset, software reset, or RESET-, drive 1 shall negate PDIAG- within 1 ms (to indicate
to device 0 that it is busy). Drive 1 shall then assert PDIAG- within 30 seconds to indicate that it is no longer
busy and is able to provide status.
Following the receipt of a valid Execute Drive Diagnostics command, device 1 shall negate PDIAG- within 1
ms to indicate to device 0 that it is busy and has not yet passed its drive diagnostics. If device 1 is present then
device 0 shall wait up to 6 seconds from the receipt of a valid Execute Drive Diagnostics command for drive 1
to assert PDIAG-. Device 1 should clear BSY before asserting PDIAG-, as PDIAG- is used to indicate that
device 1 has passed its diagnostics and is ready to post status.
If device 1 did not assert DASP- during reset initialization, device 0 shall post its own status immediately after
it completes diagnostics and clear the device 1 Status register to 00h. Device 0 may be unable to accept com-
mands until it has finished its reset procedure and is ready (DRDY=1).
Device 1 shall release PDIAG-/CBLID- no later than after the first command following a power on or hardware
reset sequence so that the host may sample PDIAG-/CBLID- in order to detect the presence or absence of an 80-
conductor cable assembly.
CSEL (Cable Select)
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.
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 this line to 5 volts.
Deskstar 7K160 Hard Disk Drive Specification
25