Seagate SCSI Interface Product Manual page 104

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[16] An ADR32 bit of one indicates the drive supports 32-bit wide SCSI addresses. Zero indicates non-sup-
port.
[17] An ADR16 bit of one indicates the drive supports 16-bit wide SCSI addresses. Zero indicates non-sup-
port. A zero in both bits [16] and [17] indicates the drive supports only 8-bit SCSI addresses.
[18] A Relative Address (RelAdr) bit of one indicates that the drive supports the relative addressing mode. If
this bit is set to one, the Linked command (Linked) bit shall also be set to one since relative addressing
can only be used with linked commands. A RelAdr bit of zero indicates the drive does not support relative
addressing.
[19] A Wide Bus 32 (WBus32) bit of one indicates that the drive supports 32-bit wide data transfers. A value of
zero indicates that the drive does not support 32-bit wide data transfers.
[20] A Wide Bus 16 (WBus16) bit of one indicates that the drive supports 16-bit wide data transfers. A value of
zero indicates that the drive does not support 16-bit wide data transfers.
Note. If the values of both the WBus16 and WBus32 bits are zero, the drive only supports 8-bit wide data
transfers.
[21] A Synchronous Transfer (Sync) bit of one indicates that the drive supports synchronous data transfer. A
value of zero indicates the drive does not support synchronous data transfer.
[22] A Linked Command (Linked) bit of one indicates that the drive supports linked commands. A value of zero
indicates the drive does not support linked commands.
[23] When the Transfer Disable (TrnDis) bit is one, it indicates that the drive supports the Continue Task and
Target Transfer Disable messages. When this bit is zero, it indicates the drive does not support the above
two messages.
[24] A Command Queuing (CmdQue) bit of one indicates that the device supports tagged tasks (command
queuing) for this logical unit (see ANSI document SCSI-3 Architectural Model-2, T10/1157). A value of
zero indicates the device server may support tagged tasks for this logical unit (see note [10]). Table 51
summarizes the relationship of the BQue and CmdQue bits.
Table 51: Relationship of BQue and CmdQue bits
BQue CmdQue
0 0
0 1
1 0
1 1
[25] A Soft Reset bit of zero indicates that the drive responds to the reset condition with the Hard Reset alter-
native (see Section 3.2.2). A Soft Reset bit of one indicates that the drive responds to the Reset condition
with the Soft Reset alternative (see Section 3.2.2).
[26] The Vendor Identification field contains the ASCII data giving vendor name ("SEAGATE").
[27] The Product Identification field contains ASCII data giving the drive model number. The data shall be left-
aligned within this field.
[28] The Product Revision Level field contains the four bytes of ASCII data "XXXX," where the value of XXXX
is the last 4 digits of the Firmware Release number.
[29] The Drive Serial Number field contains the 8 bytes of ASCII data "XXXXXXXX," where the value
XXXXXXXX is the drive serial number.
[30] The reserved area from byte 56 through byte 95 is filled with 00h.
[31] The Copyright Notice field contains the 48 bytes of ASCII data "Copyright (c) 199X Seagate All rights
reserved," where "X" indicates the current year.
[32] The Distribution Diskette Serial Number field contains the 4bytes of ASCII data "XXXX," where the value
XXXX is the Distribution Diskette serial number.
Description
No command queuing of any kind supported.
Command queuing with all types of task tags supported.
Basic command queuing (limited types of task tags) supported.
Illegal combination of BQue and CmdQue bits.
SCSI Interface Product Manual, Rev. J