Read Buffer - Quantum FIREBALL PLUS AS 10.2 Product Manual

ATA Bus Interface and ATA Commands
6.7.19 6.7.19 6.7.19 6.7.19

READ BUFFER

READ BUFFER READ BUFFER READ BUFFER
COMMAND CODE – E4h
DESCRIPTION – The READ BUFFER command enables the host to read the
current contents of the drive's sector buffer. When the host issues this command,
the drive sets BSY, sets up the sector buffer for a read operation, sets DRQ, clears
BSY, and generates an interrupt. The host then reads up to 512 bytes of data from
the buffer.
INPUTS
Register Register
Register Register
Features
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/ Head
Command
OUTPUTS
Register Register
Register Register
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/ Head
Status
6-58 Quantum Fireball Plus AS 10.2/20.5/30.0/40.0/60.0 GB AT
7 7 7 7 6 6 6 6 5 5 5 5
na
na
na
na
na
obs na obs
E4h
7 7 7 7 6 6 6 6 5 5 5 5
na na na
na
na
na
na
obs na obs
BSY DRDY DF
4 4 4 4 3 3 3 3 2 2 2 2
DEV na
4 4 4 4 3 3 3 3 2 2 2 2
na na ABRT
DEV na na
na DRQ na
1 1 1 1 0 0 0 0
1 1 1 1 0 0 0 0
na na
na na
na ERR