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AT INTERFACE and ATA COMMANDS
6-
20 WA31273A / WA32543A / WA33203A / WA3216A / WA31083A / WA32162A
Table 6-5.
Diagnostic Codes
Code
Description
01h
No error detected
02h
Formatter device error
03h
Sector buffer error
04h
ECC circuitry error
05h
Controlling microprocessor error
8xh
Drive 1 failed
6-4-3 Format Track (50h)
The track address is specified in the Cylinder High and Cylinder Low Registers, and the
number of sectors is specified in the Sector Count Register. When the command is
accepted, the drive sets the DRQ bit and waits for the host to fill the sector buffer. When
the sector buffer is full, the drive clears DRQ, sets BSY and begins command execution.
WN310820A/WN321620A hard disk drives write zeros to the data fields in the sectors
on the specified logical track. The ID fields are not written by this command.
6-4-4 Identify Device (ECh)
The Identify Device command enables the host to receive parameter information from
the device. When the command is issued, the device sets BSY bit, prepares to transfer
the 256 words of device identification data to the host, sets the DRQ bit, clears the BSY
bit, and generates an interrupt. The host cab then transfer the data by reading the Data
register. The parameter words in the buffer have the arrangement and meanings defined
in Table 6-6. All reserved bits or words shall be zero.
The F/V column indicates if the word or part of a word had fixed (F) contents that do
not change, variable (V) contents that may change depending on the device state or the
commands executed by the device, X for words with vendor specific data which may be
fixed or variable, and R for reserved words which shall be zero. For removable media
devices, the value of fields indicated as fixed (F) may change when media is removed or
changed.
Some parameters are defined as a group of bits. A word which 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).
Some parameters are defined as a sixteen bit value. A word which is defined as a sixteen
bit value places the most significant bit of the value on bits DD15 and the least
significant bit on bit DD0.