Table 8:

Receive SCSI bus data and information phase DT timing values

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Timing values for negotiated transfer rate in nanoseconds

 

 

 

 

unless otherwise noted [1]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fast-

Fast-

Timing description

Reference

Type

Fast-10

Fast-20

Fast-40

Fast-80

160

320

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ATN receive setup time

2.5.3

min

13.6

7.8

4.9

3.45

3.0

3.0

 

 

 

 

 

 

 

 

 

Flow control receive hold time

2.5.13

min

11.6

5.8

2.9

1.45

3.0

3.0

 

 

 

 

 

 

 

 

 

Flow control receive setup time

2.5.14

min

18.6

12.8

9.9

8.45

3.0

3.0

 

 

 

 

 

 

 

 

 

pCRC receive hold time

2.5.17

min

11.6

5.8

2.9

1.45

N/A

N/A

 

 

 

 

 

 

 

 

 

pCRC receive setup time

2.5.18

min

18.6

12.8

9.9

8.45

N/A

N/A

 

 

 

 

 

 

 

 

 

Receive assertion period [2]

2.5.30

min

80

40

20

8.5

4.74

1.615

 

 

 

 

 

 

 

 

 

Receive hold time [2] [3]

2.5.31

min

11.6

5.8

2.9

1.45

-0.08

-6.635

 

 

 

 

 

 

 

 

 

Receive negation period [2]

2.5.34

min

80

40

20

8.5

4.74

1.615

 

 

 

 

 

 

 

 

 

Receive setup time [2] [3]

2.5.35

min

11.6

5.8

2.9

1.45

-6.33

-9.76

 

 

 

 

 

 

 

 

 

Receive REQ(ACK) period toler-

2.5.36

min

0.7

0.7

0.7

0.7

0.06

0.06

ance

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Receive REQ assertion period

2.5.37

min

85.5

48

32.5

21

N/A

N/A

with P_CRCA transitioning

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Receive REQ negation period

2.5.38

min

85.5

48

32.5

21

N/A

N/A

with P_CRCA transitioning

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Receive skew compensation

2.5.39

max

N/A

N/A

N/A

N/A

N/A

N/A

 

 

 

 

 

 

 

 

 

Receive internal hold time [4]

2.5.32

min

N/A

N/A

N/A

N/A

0.345

0.032

 

 

 

 

 

 

 

 

 

Receive internal setup time [4]

2.5.33

min

N/A

N/A

N/A

N/A

0.345

0.032

 

 

 

 

 

 

 

 

 

Receiver de-skewed data valid

2.5.12

min

N/A

N/A

N/A

N/A

±2.1

± 1.1

window [4]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[1]SCSI bus timing values specified by the maximum transfer rate for the given range shall apply even if a slower transfer rate within the given range is negotiated.

[2]See Section 2.6 for measurement points for the timing specifications.

[3]See Section 9.6 in the ANSI SCSI Parallel Interface-5 (SPI-5) specification for examples of how to calcu- late setup and hold timing.

[4]Calculated assuming timing budget shown in Table 9.

Note. Fast-160 and fast 320 SCSI devices shall not change timing parameters between training or reset events.

24

Parallel SCSI Interface Product Manual, Rev. A )

Page 38
Image 38
Seagate Ultra 320, Ultra 160 manual Receive Scsi bus data and information phase DT timing values