Fujitsu MCJ3230SS, Руководство по эксплуатации продукта

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Host Interface
4-46 C156-E224-01EN
4.5 Timing Rule
Table 4.75 Timing specifications (1 of 3)
No. Name Standard Timing specification
1 Arbitration
Delay 2.4 µs min. The minimum wait period between the time the
SCSI device sends a BSY signal and the time the
value on the data bus for determining the
priority of bus use is judged in the
ARBITRATION phase. A maximum time is not
defined.
2 Assertion Period 90 ns min. Minimum pulse width of an ACK signal sent by
INIT and an REQ signal sent by TARG for
synchronous data transfer.
3 Bus Clear Delay 800 ns max. Maximum allowable period between the time
either of the following events occurs and the
time the SCSI device stops driving all bus
signals.
(1) Detection of the BUS FREE phase (when
both BSY and SEL signal become false
during Bus Settle Delay).
Note:
Maximum allowable period between
the time both BSY and SEL signal
became false and the time the bus is
released is 1,200 ns.
An SCSI device that requires a period
longer than Bus Settle Delay for the
detection of the BUS FREE phase
must release the bus within (Bus Clear
Delay) minus (Bus Settle Delay excess
time).
(2) Another SCSI device asserts the SEL signal
during an ARBITRATION phase.
(3) The RST signal becomes true (RESET
condition).
4 Bus Free Delay 800 ns min. Minimum wait period between the time the
SCSI device detects a BUS FREE phase and the
time it sends a BSY signal to initiate an
ARBITRATION phase.
5 Bus Set Delay 1.8 µs max. Maximum allowable period between the time an
SCSI device detects a BUS FREE phase and the
time it sends BSY and SCSI ID signals to
initiate an ARBITRATION phase.