Fujitsu MHA2021AT Product Manual page 106

This command is operated under the following conditions:
The command is issued in a sequence of the READ LONG or WRITE LONG
(to the same address) command issuance. (WRITE LONG command can be
continuously issued after the READ LONG command.)
If above condition is not satisfied, the command operation is not guaranteed.
1F7
1F6
1F5
1F4
1F3
1F2
1F1
R = 0
R = 1
1F7
1F6
1F5
1F4
1F3
1F2
1F1
*1 If the command is terminated due to an error, this register indicates 01.
(19) READ BUFFER (X'E4')
The host system can read the current contents of the sector buffer of the device by
issuing this command. Upon receipt of this command, the device sets the BSY bit
of Status register and sets up the sector buffer for a read operation. Then the
device sets the DRQ bit of Status register, clears the BSY bit, and generates an
interrupt. After that, the host system can read up to 512 bytes of data from the
buffer.
C141-E042-01EN
At command issuance (I/O registers setting contents)
(CM) 0 0
H
(DH) L
H
(CH) Cylinder No. [MSB] / LBA
H
(CL) Cylinder No. [LSB] / LBA
H
(SN) Sector No. / LBA [LSB]
H
(SC) 01
H
(FR) xx
H
with Retry
without Retry
At command completion (I/O registers contents to be read)
(ST) Status information
H
(DH) L
H
(CH) Cylinder No. [MSB] / LBA
H
(CL) Cylinder No. [LSB] / LBA
H
(SN) Sector No. / LBA [LSB]
H
(SC) 00 (*1)
H
(ER) Error information
H
1 1 0 0
DV Head No. /LBA [MSB]
DV Head No. /LBA [MSB]
5.3 Host Commands
1 R
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