Motorola MVME2400 用户手册
3-8
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Functional Description
3
PCI Bus Latency
The following table lists the latency of PCI originated transactions for five
different clock ratios: 5:2, 3:2, 3:1, 2:1, and 1:1. The MVME2400 uses a
3:1 clock ratio:
different clock ratios: 5:2, 3:2, 3:1, 2:1, and 1:1. The MVME2400 uses a
3:1 clock ratio:
Table 3-3. PCI Originated Latency Matrix
Transaction
32-bit PCI
64-bit PCI
Clock
Ratio
Beat
1
Beat
2
Beat
3
Beat
4
Total
Beat
1
Beat
2
Beat
3
Beat
4
Total
Burst Read
9
1
1
1
12
9
1
1
1
12
5:2
Burst Write
3
1
1
1
6
3
1
1
1
6
Single Read
9
-
-
-
9
9
-
-
-
9
Single Write
3
-
-
-
3
3
-
-
-
3
Burst Read
12
1
1
1
15
12
1
1
1
15
3:2
Burst Write
3
1
1
1
6
3
1
1
1
6
Single Read
12
-
-
-
12
12
-
-
-
12
Single Write
3
-
-
-
3
3
-
-
-
3
Burst Read
9
1
1
1
12
9
1
1
1
12
3:1
Burst Write
3
1
1
1
6
3
1
1
1
6
Single Read
9
-
-
-
9
-
-
-
-
-
Single Write
3
-
-
-
3
-
-
-
-
-
Burst Read
11
1
1
1
14
11
1
1
1
14
2:1
Burst Write
3
1
1
1
6
3
1
1
1
6
Single Read
11
-
-
-
11
-
-
-
-
-
Single Write
3
-
-
-
3
-
-
-
-
-
Burst Read
16
1
1
1
19
16
1
1
1
19
1:1
Burst Write
3
1
1
1
6
3
1
1
1
6
Single Read
16
-
-
-
16
-
-
-
-
-
Single Write
3
-
-
-
3
-
-
-
-
-