5.SCSI Interface
5.3.11.BUS DEVICE RESET (0Ch)
This message is sent from an initiator to direct a target to clear all current commands. Upon recognizing this message, the currently executing command will be aborted and the drive will proceed to the BUS FREE state. The drive will then execute a hard reset which will leave the drive in a state as if it had been
A BUS DEVICE RESET message should be used to reset the drive, rather than a hard reset, as this will only reset the drive rather than all the devices on the bus.
Due to the catastrophic nature of this command, it should be used cautiously in a multiple initiator system.
5.3.12.IDENTIFY (80h-FFh)
These messages are sent by either the initiator or the target to establish the physical connection path between an initiator and target for a particular logical unit. This message byte can have the following bits set:
Bit 7 | This bit is always set to one to distinguish these messages from other messages. |
Bit 6 | This bit is only set to one by the initiator. When set to one, it indicates that the initiator has the ability to |
| disconnect and reconnect. |
Bit 5 | LUNTAR: This bit is always ZERO to indicate that the LUNTRN field below is valid. |
Bits | Reserved. |
Bits
Therefore, only the values 80h and C0h are supported.
When sent from a target to an initiator during reconnection, an implied RESTORE POINTERS message will be performed by the initiator prior to completion of this message, since at no time will a RESTORE POINTERS be sent.
5.3.13.IGNORE WIDE RESIDUE (23h)
Table 5-5: Ignore Wide Residue Message
Byte | Value |
|
0 | 23 | Message Code |
1 | 01 | Ignore |
The IGNORE WIDE RESIDUE message (see table
| Table | |
|
|
|
Ignore |
| Invalid data bits |
|
| |
00h |
| Reserved |
01h |
| DB |
| Reserved |
Even though a byte is invalid its corresponding parity bit shall be valid for the value transferred.
SONY |