SCSI Primary Commands - 2.pdf

18 July 2001 T10/1236-D Revision 207.25 TEST UNIT READY commandThe TEST UNIT READY command (see table 116) provides a means to check if the logical unit is ready. This is nota request for a self-test. If the logical unit is able to accept an appropriate medium-access command withoutreturning CHECK CONDITION status, this command shall return a GOOD status. If the logical unit is unable tobecome operational or is in a state such that an application client action (e.g., START UNIT command) is requiredto make the unit ready, the device server shall return CHECK CONDITION status with a sense key of NOT READY.Table 116 — TEST UNIT READY commandBitByte7 6 5 4 3 2 1 00 OPERATION CODE (00h)1 Reserved2 Reserved3 Reserved4 Reserved5 CONTROLTable 117 defines the suggested GOOD and CHECK CONDITION status responses to the TEST UNIT READYcommand. Other conditions, including deferred errors, may result in other responses (e.g., BUSY or RESER-VATION CONFLICT status).Table 117 — Preferred TEST UNIT READY responsesStatus Sense Key Additional Sense CodeGOOD NO SENSE NO ADDITIONAL SENSE INFORMATION orother valid additional sense code.CHECK CONDITION ILLEGAL REQUEST LOGICAL UNIT NOT SUPPORTEDCHECK CONDITION NOT READY LOGICAL UNIT DOES NOT RESPONDTO SELECTIONCHECK CONDITION NOT READY MEDIUM NOT PRESENTCHECK CONDITION NOT READY LOGICAL UNIT NOT READY,CAUSE NOT REPORTABLECHECK CONDITION NOT READY LOGICAL UNIT IS IN PROCESSOF BECOMING READYCHECK CONDITION NOT READY LOGICAL UNIT NOT READY,INITIALIZING COMMAND REQUIREDCHECK CONDITION NOT READY LOGICAL UNIT NOT READY,MANUAL INTERVENTION REQUIREDCHECK CONDITION NOT READY LOGICAL UNIT NOT READY,FORMAT IN PROGRESSdpANS SCSI Primary Commands - 2 (SPC-2) 163