Read Buffer (E4H); Table 95.Read Buffer (E4H) - Hitachi 7K80 - Deskstar - Hard Drive Specifications

12.14 Read Buffer (E4h)

Table 96: Read Buffer (E4h)
Command Block Output Registers
Register
Data
Feature
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Command
Error Register
7 6 5
CRC UNC 0
0 0 0
The Read Buffer command transfers a sector of data from the sector buffer of the device to the host.
The sector is transferred through the Data Register 16 bits at a time.
The sector transferred will be from the same part of the buffer written to by the last Write Buffer command. The
contents of the sector may be different if any reads or writes have occurred since the Write Buffer command was
issued.
7 6 5 4 3 2 1 0
- - - - - - - -
- - - - - - - -
V V V V V V V V
- - - - - - - -
- - - - - - - -
- - - - - - - -
1 - 1 D - - - -
1 1 1 0 0 1 0 0
4 3 2 1
IDN 0 ABT T0N AMN
0 0 V 0
Deskstar 7K80 Hard Disk Drive Specification
Command Block Input Registers
Register
Data
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Status
0 7 6
BSY RDY DF DSC DRQ
0 0 V
146
7 6 5 4 3 2 1 0
- - - - - - - -
see below
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
see below
Status Register
5 4 3 2
COR IDX
0 - - 0
1 0
ERR
- V