Avago Technologies LSI8751D User Manual
Page 133
5-17
MO[4:0]
Max SCSI Synchronous Offset
[4:0]
These bits describe the maximum SCSI synchronous
offset used by the LSI53C875 when transferring
synchronous SCSI data in either initiator or target mode.
describes the possible combinations and their
relationship to the synchronous data offset used by the
LSI53C875. These bits determine the LSI53C875’s
method of transfer for Data-In and Data-Out phases only.
All other information transfers occur asynchronously.
Table 5.3
Example Transfer Periods for Fast SCSI-2 and Ultra SCSI Transfer Rates
CLK
(MHz)
SCSI CLK
÷
SCNTL3
Bits [6:4]
XFERP
Synch. Send
Rate
(Mbytes/s)
Synch.
Transfer
Period (ns)
Synch. Receive
Rate (Mbytes)
Synch.
Receive
Period (ns)
80
1
4
20.0
50
20.0
50
80
2
4
10.0
100
10.0
100
66.67
1.5
4
11.11
90
11.11
90
66.67
1.5
5
8.88
112.5
11.11
90
50
1
4
12.5
80
12.5
80
50
1
5
10.0
100
12.5
80
40
1
4
10.0
100
10.0
100
37.50
1
4
9.375
106.67
9.375
106.67
33.33
1
4
8.33
120
8.33
120
25
1
4
6.25
160
6.25
160
20
1
4
5
200
5
200
16.67
1
4
4.17
240
4.17
240