SCSI Bus Timing

Unless otherwise indicated, the delay time measurements for each SCSI device, shown in Table 3.5., shall be calculated from signal conditions existing at that SCSI device’s own SCSI bus connection. Thus, these measurements (except cable skew delay) can be made

without considering delays in the cable. The timing characteristics of INTERFACE each signal are described in the following paragraphs.

Table 3.5 SCSI Bus Timing Values
Timing DescriptionTiming Values

 

 

Arbitration Delay

2.4 μs

 

 

Assertion Period

90 ns

 

 

Bus Clear Delay

800 ns

Bus Free Delay

800 ns

 

 

Bus Set Delay

1.8 μs

 

 

Bus Settle Delay

400 ns

Cable Skew Delay

10 ns

 

 

Data Release Delay

400 ns

 

 

Deskew Delay

45 ns

Disconnection Delay

200 μs

 

 

Hold Time

45 ns

 

 

Negation Period

90 ns

Power-On to Selection Time

10 s recommended

 

 

Reset to Selection Time

25 μs

 

 

Reset Hold Time

200 μs

Selection Abort Time

200 μs

 

 

Selection Time-out Delay

250 ms recommended

 

 

Transfer Period

set during an SDTR message

 

 

M3099GX/GH OEM Manual

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