Command Sequence - Spectra Logic Spectra 10000 User Manual

10kdev_.book Page 5 Friday, March 12, 1999 9:44 AM

Command Sequence

The previous table shows the SSCL phases and command sequence.
•
The command sequence is identical whether the library is interfacing with a host
system running backup software or a terminal connected to the RS-232 port.
•
The library must receive a
accept a command.
•
After successfully completing a command, the library responds with
an
Acknowledge
returns an ASCII
•
If you send a command to the library and it is not in the
nothing. Re-issue a
•
Commands are transmitted to the library with a carriage return,
Initialize Phase At power up the serial port, the front panel, and the SCSI port enter the
Initialize Phase
occurs during the initialization, the library generates hardware error sense code data.
Use
Note:
regarding the error. Clear the cause of the error, then reset the library.
During initialization, the library will respond to a limited number of commands. These
commands are I, E and ctl+e.
Idle Phase After power up and initializing, the library enters the
idle and is waiting for a
Command Phase
Command Phase The library is waiting for a command.The library can only accept
commands while in the
from the
Phase
The library returns an
Issue Phase A command has been issued with a carriage return,
and the library is processing that command. The
the command status to the host.
•
ACK
•
NAK
If the command is successful, the library will either return to the
another command or enter the
If the library returns a
Note:
determine the error, clear the sense condition, and return the library to the
.
Phase
Synchronous Character, SYN
, or character. After an unsuccessful operation the library
ACK
Not-Acknowledged (NAK)
SYN command,
. The library initializes and performs a self-test initialization. If an error
, command
Request Sense
Synchronous Character, SYN
.
Command Phase,
. To enter the
Idle Phase
character.
ACK
indicates the command is successful; library returns to
indicates an error executing the command; library returns to
Data Phase
, use
NAK
, (ctl+v) before it will
character.
Command Phase
then try the command again.
, to access and clear the sense information
E
Idle Phase
, (ctl+v) before entering the
and the library can only enter the
, issue a
Command Phase
SYN
<cr>
ends when the library returns
Issue Phase
Idle Phase
Idle Phase
.
, command
Request Sense
it may return
.
<CR>
. The library is
Command
(ctl+v) to the library.
, from the terminal
Idle Phase
and wait for
, to
E
Idle