Bus Free Phase - Fujitsu M3096GX Instruction Manual

Table 4.4 Signal delay times definition (3/3)
No. Item
14 Reset to 250 ms
selection (recom>
time mended)
15 Reset hold 25 os
time
16 Selection 200 os
abort time
17 Selection 250 ms
timeout (recom>
delay mended)
18 Transfer
period
4.3.1

BUS FREE phase

The BUS FREE phase is used to indicate that no SCSI device is actively using the
SCSI bus, and that it is available.
SCSI devices shall detect the BUS FREE phase after the SEL and BSY signals are
both false for at least a bus settle delay.
SCSI devices shall release all SCSI bus signals within a bus clear delay after the
BSY and SEL signals become continuously false for a bus settle delay.
BSY
SEL
others
4 $ 12
Time
The recommended maximum time after a hard RESET
condition until an SCSI target is able to respond with
appropriate status and sense data to the TEST UNIT
READY, INQUIRY, and REQUEST SENSE commands
The minimum time over which RST must be kept asserted
The maximum time required from the moment when
selection or deselection of an initiator or target is detected
until BSY is asserted
The minimum time required for an initiator or target in
the selection or deselection phase to wait for a BSY
response before it starts the timeout procedure
The minimum allowable period, during sync data
transfer, between the start of consecutive REQ pulses and
the start of consecutive ACK pulses
bus settle delay
Definition
bus clear delay
BUS FREE phase