Table 5.91 Read Buffer Header - Hitachi Ultrastar 15K73 Reference Manual

(3) Data
In this mode, a header is not transferred but the data is transferred starting
from the address as specified in the Buffer Offset field.
(4) Descriptor
In this mode, the 4-byte Read Buffer Descriptor (see Table 5.92) is Transferred.
The Buffer Offset must be specified to 0 and the Allocation Length must be
specified to 4 or more.
(5) Echo Buffer
In this mode, transfer the same data as when the WRITE BUFFER command
with the mode field set to echo buffer was issued.
(6) Echo Buffer Descriptor
In this mode, the 4-byte Echo Buffer Descriptor (see Table 5.93) is Transferred.
Byte
0
1
2
3
The Buffer Capacity indicates the maximum length of the READ BUFFER data (i.e.,
the length is from Buffer Offset to the last address of Buffer.
Offset is set to 0, the length is equal to the buffer size. ) that the controller may
transfer to the host computer.
It is recommended that the host computer issues the RESERVE command to this
controller prior to the WRITE BUFFER command and that it issue the RELEASE
command after the READ BUFFER command is completed, to avoid corruption of the
controller buffer by other host computers.
READ BUFFER:(3Ch)
5 COMMAND DESCRIPTIONS

Table 5.91 Read Buffer Header

0 0 0
READ BUFFER Header
Reserved
0 0
Buffer Capacity (MSB)
Buffer Capacity
Buffer Capacity (LSB)
OEM MANUAL:K6602924
0 0 0
And if the Buffer
Revision: 1 / Date: 2003.03.06
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