3

Falcon ECC Memory Controller Chip Set

Table 3-3. PowerPC 60x Bus to DRAM Access Timing — 60ns Page Devices.

 

 

Clock Periods Required For:

 

Total

Access Type

 

 

 

 

 

 

1st

 

2nd

3rd

 

4th

 

 

Clocks

 

 

 

 

Beat

 

Beat

Beat

 

Beat

 

 

 

 

 

 

 

 

 

4-Beat Read after Idle (Quad-

9

 

1

2

 

1

13

word aligned)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4-Beat Read after Idle (Quad-

9

 

3

1

 

1

14

word misaligned)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4-Beat Read after 4-Beat Read

7/3 1

 

1

2

 

1

11/7

(Quad-word aligned)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4-Beat Read after 4-Beat Read

6/2 1

 

3

1

 

1

11/7

(misaligned)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4-Beat Write after Idle

4

 

1

1

 

1

7

 

 

 

 

4-Beat Write after 4-Beat Write

7/3 1

 

1

1

 

1

10/6

(Quad-word aligned)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1-Beat Read after Idle

9

 

-

-

 

-

9

 

 

 

 

1-Beat Read after 1-Beat Read

9/6 1

 

-

-

 

-

9/6

1-Beat Write after Idle

4

 

-

-

 

-

4

 

 

 

 

 

 

 

1-Beat Write after 1-Beat Write

13/10

1

-

-

 

-

13/10

 

 

 

 

 

 

 

 

 

Notes

1.These numbers assume that the PowerPC 60x bus master is doing address pipelining with TS_ occurring at the minimum time after AACK_ is asserted. Also, the two numbers shown in the 1st Beat column are for page miss/page hit.

2.In some cases, the numbers shown are averages and specific instances may be longer or shorter.

3-8

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Motorola MVME2300 Series manual PowerPC 60x Bus to Dram Access Timing 60ns Page Devices, 2nd 3rd 4th Clocks Beat