Quantum DLTtape SDLT 220, Руководство пользователя

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SDLT 220 and SDLT 320 Product Manual CHAPTER 6: SCSI Description
81-85002-01 March 2004 6-11
Disconnection Delay 200 µs Minimum time that a drive waits after releasing BSY before
participating in an ARBITRATION when honoring a
DISCONNECT message from the initiator.
Hold Time 45 ns Minimum time added between the assertion of REQ or ACK and
changing the data lines to provide hold time in the initiator or
drive while using standard (slow) synchronous data transfers.
Negation Period 90 ns Minimum time that a drive negates REQ while using
synchronous data transfers; also, the minimum time than an
initiator negates ACK while using synchronous data transfers.
1
Power-On to Selection
10 s
1
Recommended maximum time from power application until a
drive is able to respond with appropriate status and sense data to
the TEST UNIT READY, INQUIRY, and REQUEST SENSE
commands.
Reset to Selection Time
250 ms
1 Recommended maximum time after a hard RESET condition
until a drive is able to respond with appropriate status and sense
data to the TEST UNIT READY, INQUIRY, and REQUEST
SENSE commands.
Reset Hold Time 25 µs Minimum time for which RST is asserted; there is no maximum
time.
Selection Abort Time 200 µs Maximum time that a drive (or initiator) takes from its most
recent detection of being selected (or reselected) until asserting a
BSY response.
Selection Time-Out
Delay
250 ms
1
Recommended minimum time a SCSI device should wait for a
BSY response during SELECTION or RESELECTION before
starting the time-out procedure.
Transfer Period
2 100 ns <
time
< 500 ns Minimum time allowed between the leading edges of successive
REQ pulses and of successive ACK pulses while using standard
or fast synchronous data transfers. The period range is 200 to
500ns minimum, standard, or 100 to 500ns minimum, fast-
synchronous.
1. Recommended time.
2. Set during an SDTR message.
Table 6-5. SCSI Bus Timing Values (Continued)