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FUJITSU MCJ3230SS User Manual

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4.5 Timing Rule

C156-E224-01EN

4-49

Table 4.76 FAST SCSI Timing specifications

No.

Name

Standard

Timing specification

18

Fast Assertion
Period

30 ns min.

In FAST SCSI data transfer mode, minimum
pulse width of an ACK signal sent by INIT and
an REQ signal sent by TARG for synchronous
data transfer.

19

Fast Cable Skew
Delay

5 ns max.

In FAST SCSI data transfer mode, maximum
allowable difference in transmission time over
the interface cable between any two bus signals
from any two SCSI devices.

20

Fast Deskew
Delay

20 ns min.

In FAST SCSI data transfer mode, time for
compensation for skew involved in bus signal
transmission.

21

Fast Hold Time

10 ns min.

In FAST SCSI data transfer mode, the minimum
time during which the transfer data on the
DATA BUS from the leading edge of the REQ
or ACK signal pulse must be maintained to
compensate for the hold time in the SCSI device
receiving data.

22

Fast Negation
Period

30 ns min.

In FAST SCSI data transfer mode, the minimum
time from the trailing edge of an REQ signal to
the leading edge of the next REQ signal, or from
the trailing edge of an ACK signal to the leading
edge of the next ACK signal.

Figure 4.4 BUS FREE phase