Quantum Instruments DLT 7000 manual Scsi Description

		SCSI Description
Table 3–4 SCSI Bus Timing Values (continued)
Timing Description	Value	Description
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	10 s1	Recommended maximum time from power
Selection		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	250	Recommended maximum time after a hard RESET
Time	ms1	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	250	Recommended minimum time a SCSI device should
Delay	ms1	wait for a BSY response during SELECTION or
		RESELECTION before starting the time-out procedure.
Transfer Period2		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.

1Recommended Time.

2Set during an SDTR message.

Quantum DLT 7000 Tape System 3-9