Fujitsu MCE3064SS, Product Manual

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7 - 20 C156-E097-01EN
Figure 7.8 RESELECTION phase
(2) Response sequence
When the SCSI device (INIT) detects that the SEL signal, I/O signal and data bus bit (DBn)
corresponding to the own SCSI ID are true and the BSY signal is false for 400 ns (Bus Settle
Delay) or more, the INIT shall recognize that the INIT itself is selected in the RESELECTION
phase. At this time, the selected INIT performs sampling to identify the SCSI ID of the TARG
that requests the reconnection.
The INIT shall respond to the TARG by asserting the BSY signal within 200
µ
s (Selection Abort
Time).
When other than 2-bit SCSI ID is detected or when the parity error is detected on the system in
which the parity bit of the data bus is valid, the INIT shall not respond to the RESELECTION
phase.
After the TARG detects the response (BSY signal) from the INIT, the TARG asserts the BSY
signal, then release the SEL signal after 90 ns (Deskew Delay
×
2) or more. After this time, the
TARG may change the I/O signal state and data bus value.
When the INIT detects that the SEL signal is false, the INIT stops sending the BSY signal.
(3) Timeout procedure
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30