National Instruments GPIB-SCSI-A, Руководство пользователя

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G Mode Functions Chapter 7
GPIB-SCSI-A User Manual 7-4 © National Instruments Corp.
autotst - Enable/Disable Automatic Testing of
SCSI Targets
Type: SCSI Configuration function
Syntax:
autotst [target ids]
<CR>
or
autotst?
<CR>
Purpose: Use
autotst
if you want to verify that a given set of SCSI
Targets is still online and ready to receive commands.
Remarks: This command allows the user to automatically test specific
Targets in order to verify that they are still online and ready to
receive commands. The testing is done between the execution
of G mode functions, when the GPIB-SCSI-A would
otherwise be idle.
target ids
is a list of SCSI Target ids to test. If no
target ids
are specified, the
autotst
function is
disabled, and no automatic testing is done. This is also the
default behavior for the
autotst
function.
If one or more
target ids
are specified, the GPIB-SCSI-A
configures itself to automatically test those Targets.
Thereafter, approximately once every three seconds, the
GPIB-SCSI-A issues the Test Unit Ready command to every
Target that is configured for automatic testing. The Test Unit
Ready command is issued in the same manner as the
tstur
function. The three second timer stops when the
GPIB-SCSI-A receives a valid G mode function. It is
restarted after completing the function.
If a specified SCSI Target cannot be Selected (due to being
powered off), a phase error occurs during the command or if
the Status byte returned by a Target is CHECK CONDITION,
an error condition is indicated to the user. This error is
indicated by setting the ERR bit in the internal GPIB-SCSI-A
status, and by setting the SCSI error code to a value in the