Error Register; Features Register; Sector Count Register; Figure 57. Error Register - IBM IC25N020ATDA04 - Travelstar 20 GB Hard Drive Specifications

10.8 Error Register

Figure 57. Error Register

This register contains the status from the last command executed by the device or a diagnostic code. At
the completion 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 Figure 61 on page 79 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 (ABT) Aborted Command. When ABT = 1 it indicates that the requested command has been
aborted due 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
Recalibrate command.
AMNF (AMN) 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.

10.9 Features Register

This register is command specific. This register is used with the Set Features command, the S.M.A.R.T.
Function Set command, and the Format Unit command.

10.10 Sector Count Register

This register contains the number of sectors of data requested to be transferred on a read or write
operation between the host and the device. If the value in the register is set to 0, a count of 256 sectors
is specified.
If the register is zero at command completion, the command was successful. If it was not successfully
completed, the register contains the number of sectors which need to be transferred in order to complete
the request.
The contents of the register are defined differently on some commands. These definitions are given in
Section 13.0, "Command descriptions" on 109.
Error Register
7 6 5
CRC UNC 0 IDNF
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
4 3 2 1
0 ABRT TK0N
75
0
AMN