K6610170
Rev.2
Dec 22, 2004
- 89 -
7.5.25. Read Verify [40h, 41h]
Task
File
Registers
7 6 5 4 3 2 1 0
Command
40h or 41h
LBA High
L = 0: Cylinder number bit 15 - 8
L = 1: 28-bit LBA address bit 23 - 16
LBA Mid
L = 0: Cylinder number bit 7 - 0
L = 1: 28-bit LBA address bit 15 - 8
LBA Low
L = 0: Sector number
L = 1: 28-bit LBA address bit 7 - 0
Device/Head
X
L
X
DRV L = 0:
Head Number
L = 1:
28-bit LBA address
bit 27-24
Sector Count
Sector Count
Features
XX
The READ VERIFY command is same as the READ SECTORS command, except that DRQ is never set
and no data is transferred to the host. When the requested sectors have been verified, the device clears
BSY and generates an interrupt. Upon command completion, the Command Block Registers contain the 28-
bit LBA address or cylinder/head/sector numbers of the last sector verified. If an error occurs, the verify
terminates at the sector where the error occurs. The Command Block Registers contain the 28-bit LBA
address or cylinder/head/sector numbers of the sector where the error occurred. The Sector Count Register
contains the number of sectors not yet verified.