A SCSI Status Code is used to determine the success or failure of a SCSI

command Command may refer to: Computing * Command (computing), a statement in a computer language * COMMAND.COM, the default operating system shell and command-line interpreter for DOS * Command key, a modifier key on Apple Macintosh computer keyboards * ...

. At the end of any command, the

target Target may refer to: Physical items * Shooting target, used in marksmanship training and various shooting sports ** Bullseye (target), the goal one for which one aims in many of these sports ** Aiming point, in field artillery, f ...

returns a Status Code

byte The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable uni ...

which should be one of the following:

00h Good

This status code indicates that the device has completed the task successfully.

02h Check Condition

When the target returns a Check Condition in response to a command it is indicating that it has entered a contingent allegiance condition. This means that an error occurred when it attempted to execute a SCSI command. The initiator usually then issues a

SCSI Request Sense command Small Computer System Interface (SCSI, ) is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, electrical, optical and logical interface ...

in order to obtain a Key Code Qualifier ( KCQ) from the target.

04h Condition Met

This status code is returned on successful completion of a Pre-fetch Command.

08h Busy

The target returns Busy if it cannot complete a command at that time, for example if it is in the contingent allegiance condition.

10h Intermediate (obsolete)

The target returns Intermediate when it successfully completes a linked command (except the last command). This status code is obsolete starting with SAM-4.

14h Intermediate - Condition Met (obsolete)

As the name suggests, this status code is simply a combination of 10h Intermediate and 04h Condition Met. This status code is obsolete starting with SAM-4.

18h Reservation Conflict

The target returns this status code if an initiator attempts to access a LUN that has been previously reserved by another initiator using the

Reserve Reserve or reserves may refer to: Places * Reserve, Kansas, a US city * Reserve, Louisiana, a census-designated place in St. John the Baptist Parish * Reserve, Montana, a census-designated place in Sheridan County * Reserve, New Mexico, a US vi ...

or Reserve Unit command.

22h Command Terminated (obsolete)

The target returns this status if the target has to terminate the current I/O process because it received a Terminate I/O Process message. This status code is obsolete starting with

SAM-2 The S-75 (Russian: С-75; NATO reporting name SA-2 Guideline) is a Soviet-designed, high-altitude air defence system, built around a surface-to-air missile with command guidance. Following its first deployment in 1957 it became one of the most w ...

28h Task Set Full

Similar to 08h Busy status, this status code is returned when the logical unit lacks the resources to accept a received task from an I_T nexus. This status code implies that the logical unit already has at least one task from that I_T nexus, where the 08h Busy status code implies that the logical unit currently has no tasks from that I_T nexus.

30h ACA Active

The target returns this status code if an auto-contingent allegiance condition has occurred.

40h Task Aborted

The target returns this status code when a task is aborted by another I_T nexus and the TAS bit in the Control mode page is set to one.

External links

*{{Cite web, url=http://www.seagate.com/staticfiles/support/disc/manuals/Interface%20manuals/100293068c.pdf, title=SCSI Commands References Manual, publisher= Seagate, accessdate=2010-12-13
SCSI Architecture Model (SAM)
clause 5.3.1

SCSI