Sony AIT-SDX470, Руководство по техническим характеристикам продукции

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6. ATA Command Specification Identify Packet Device
SONY AIT-1 Turbo drive SDX-470V series Ver.1.0 6-8
6.5. Identify Packet Device (A1h)
The IDENTIFY PACKET DEVICE command enables the host to receive parameter information from the device.
When the command is issued, the device sets the BSY bit to one, prepares to transfer the 256 words of device
identification data to the host, sets the DRQ bit to one, clears the BSY bit to zero, and asserts INTRQ if nIEN is
cleared to zero. The host may then transfer the data by reading the Data register. The following table explains the
arrangement and meanings of the parameter words in the buffer. All reserved bits or words shall be zero. Some
parameters are defined as a group of bits. A word that is defined as a set of bits is transmitted with indicated bits
on the respective data bus bit (e.g., bit 15 appears on DD15).
Inputs
Register 7 6 5 4 3 2 1 0
Features na
Sector Count na
Sector Number na
Cylinder Low na
Cylinder High na
Device/Head 1 na 1 DEV na na na na
Command A1h
Device/Head register -
DEV indicates the selected device.
Normal outputs
Register 7 6 5 4 3 2 1 0
Error na
Sector Count na
Sector Number na
Cylinder Low na
Cylinder High na
Device/Head 1 na 1 DEV na
Status BSY DRDY DF DSC DRQ na na CHK
Device/Head register -
DEV indicates the selected device.
Status register -
BSY is cleared to zero when the command is completed.
DRDY is set to one.
DF is cleared to zero.
DSC is set to one.
DRQ is cleared to zero.
CHK is cleared to zero.
Error outputs
None. This command does not end with an error.
Prerequisites
This command is accepted regardless of the state of DRDY.
Description
The IDENTIFY PACKET DEVICE command enables the host to receive parameter information from a Sony ATAPI
Tape Drive that implements the PACKET Command feature set.