Read Capacity Command - Sony CDU-541 Interface Manual

CDU-541 CD-ROM DRIVE SCSI INTERFACE MANUAL
The data to be transferred is preceded by a four-byte READ BUFFER header.
Table 5-11: Read Buffer Header
==============================================================================
Bit:
7
6
5
4
3 2
1
o
Byte :
==============================================================================
o :
Reserved :
-----:-----------------------------------------------------------------------:
1 : (MSB) :
-----:--- ---I
2 : Available Length :
----~:---
---I
3 :
(LSB) :
==============================================================================
5.2.17.
READ
CAPACITY Command
==============================================================================
Bit:
7
6
5
4
3
2
1
o
Byte :
==============================================================================
o :
Operation Code (25h) :
-----l-------------------------~---------------------------------------------:
1 : Logical Unit Number: Reserved :
-----:-----------------------------------------------------------------------:
2 : Reserved :
-----:-----------------------------------------------------------------------:
3 : Reserved :
-----:-----------------------------------------------------------------------:
4 :
Reserved :
-----:-----------------------------------------------------------------------:
5 : Reserved :
-----,-----------------------------------------------------------------------:
,
I
6 Reserved
-----------------------------------------------------------------------:
7
Reserved I
I
-----------------------------------------------------------------------:
8
Reserved I
I
-----------------------------------------------------------------------1
9
Control Byte I
I
=================================================================:============
The
READ
CAPACITY command a means for the initiator to request information
regarding the capacity of the logical unit. The eight bytes of READ CAPACITY
data is shown below. The capacity is based on the starting address of the
lead-out area minus one.
5-31