Device/Head Register; Error Register; Table 41: Device Head/Register; Table 42: Error Register - Hitachi IC25N040ATMR04-0 - Travelstar 40GB Laptop Hard Drive 9.5mm 2.5 Inch Notebook HDD Specifications

10.6 Device/Head Register

Table 41: Device Head/Register

7 6
1 L
This register contains the device and head numbers.
Bit Definitions
L Binary encoded address mode select. When L = 0, addressing is by CHS mode. When L = 1,
addressing is by LBA mode.
DRV Device. When DRV = 0, device 0 (master) is selected. When DRV = 1, device 1 (Slave) is
selected.
HS3, HS2, Head Select. These four bits indicate the binary encoded address of the head. Bit HS0 is the least
HS0 significant bit. At command completion, these bits are updated to reflect the currently selected
head. The head number may be from zero to the number of heads minus one. In LBA mode, HS3
through HS0 contain bits 24–27 of the LBA. At command completion, these bits are updated to
reflect the current LBA bits 24–27.

10.7 Error Register

Table 42: Error Register

7 6
CRC UNC
This register contains the status from the last command executed by the device or a diagnostic code. At the comple-
tion of any command, except Execute Device Diagnostic, the contents of this register are always valid even if
ERR = 0 is in the Status Register.
Following a power on, a reset, or completion of an Execute Device Diagnostic command, this register contains a
diagnostic code. See Table 46: , "Diagnostic codes," on page 70 for the definitions.
Bit Definitions
ICRCE (CRC) Interface CRC Error. When CRC = 1, it indicates that a CRC error has occurred on the data bus
during a Ultra DMA transfer.
UNC Uncorrectable Data Error. When UNC = 1 it indicates that an uncorrectable data error has been
encountered.
IDNF(IDN) ID Not Found. When IDN = 1, it indicates that the requested sector's ID field could not be found.
ABRT Aborted Command. When ABT = 1, it indicates that the requested command has been aborted due
(ABT) to a device status error or an invalid parameter in an output register.
TK0NF (T0N) Track 0 Not Found. When T0N = 1, it indicates that track 0 was not found during a recallibrate
command.
AMNF Address Mark Not Found. When AMN = 1, it indicates that the data address mark has not been
found after finding the correct ID field for the requested sector.
5 4 3
1 DRV HS3
5 4 3
0 IDNF 0
Travelstar 80GN Hard Disk Drive Specification
2 1 0
HS2 HS1 HS0
2 1
ABRT TK0NF AMNF
66
0