Fujitsu C150-E049-02EN User Manual
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M3099GX/GH OEM Manual
If an initiator detects the release of the BSY signal by the target at
any other time, the target is indicating an error condition to the
initiator. The target may perform this transition to the BUS FREE
phase independent of the state of the ATN signal. The initiator shall
manage this condition as an unsuccessful I/O process termination.
The target terminates the I/O process by clearing all pending data
and status information for the affected nexus. The target may
optionally prepare sense data that may be retrieved by a REQUEST
SENSE command.
any other time, the target is indicating an error condition to the
initiator. The target may perform this transition to the BUS FREE
phase independent of the state of the ATN signal. The initiator shall
manage this condition as an unsuccessful I/O process termination.
The target terminates the I/O process by clearing all pending data
and status information for the affected nexus. The target may
optionally prepare sense data that may be retrieved by a REQUEST
SENSE command.
ARBITRATION Phase
The ARBITRATION phase allows one SCSI device to gain control
of the SCSI so that it can initiate or resume an I/O process.
of the SCSI so that it can initiate or resume an I/O process.
The procedure for an SCSI device to obtain control of the SCSI bus
is as follows:
a) The SCSI device shall first wait for the BUS FREE phase to
is as follows:
a) The SCSI device shall first wait for the BUS FREE phase to
occur. The BUS FREE phase detected whenever both the BSY
and SEL signals are simultaneously and continuously false for a
minimum of a bus settle delay.
and SEL signals are simultaneously and continuously false for a
minimum of a bus settle delay.
b) The SCSI device shall wait a minimum of a bus free after
detection of the BUS FREE phase (i.e. after the BSY and SEL
signals are both false for a bus settle delay) before driving any
signal
signals are both false for a bus settle delay) before driving any
signal
c) 3)Following the bus free delay in Step(b), the SCSI device may
arbitrate for the SCSI bus by asserting both the BSY signal and its
own SCSI ID, however the SCSI device shall not arbitrate (i.e.
assert the BSY signal and its SCSI ID) if more than a bus settle
delay has passed since the BUS FREE phase was last observed.
own SCSI ID, however the SCSI device shall not arbitrate (i.e.
assert the BSY signal and its SCSI ID) if more than a bus settle
delay has passed since the BUS FREE phase was last observed.
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