Features Register; Sector Count Register; Sector Number Register; Status Register - IBM DTNA-22160 - Travelstar 2.1 GB Hard Drive Specifications

TK0NF (T0N) Track 0 Not Found. T 0 N = 1 indicates track 0 was not found during a Recalibrate
command.
AMNF (AMN) Address Mark Not Found. A M N = 1 indicates the data address mark has not been
found after finding the correct ID field for the requested sector.

9.10 Features Register

This register is command specific. This is used with the Set Features command.

9.11 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 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 otherwise on some commands. These definitions are given in the
command descriptions.

9.12 Sector Number Register

This register contains the starting sector number for any disk data access for the subsequent command. The
sector number is from one to the maximum number of sectors per track.
In LBA mode, this register contains Bits 0-7. At the end of the command, this register is updated to reflect
the current LBA Bits 0-7.

9.13 Status Register

7
B S Y
Figure 34. Status Register
This register contains the device status. The contents of this register are updated whenever an error occurs
and at the completion of each command.
If the host reads this register when an interrupt is pending, it is considered to be the interrupt acknowledge.
Any pending interrupt is cleared whenever this register is read.
If B S Y = 1 , no other bits in the register are valid.
S t a t u s R e g i s t e r
6 5 4
D R D Y D F D S C D R Q
3 2 1 0
C O R R I D X E R R
53
Registers