MPC8247 MOTOROLA [Motorola, Inc], MPC8247 Datasheet - Page 30

• Manufacturer Part Number: MPC8247
• Description: MPC8272 PowerQUICC II Family Hardware Specifications
• Manufacturer: MOTOROLA [Motorola, Inc]

Clock Configuration Modes
Clock Configuration Modes
1
2
3
4
5
7.2
Table 17 and Table 18 show configurations for PCI agent mode. The frequency values listed are for the
purpose of illustration only. Users must select a mode and input bus frequency so that the resulting
configuration does not exceed the frequency rating of the user’s device. Note that in PCI agent mode the
input clock is PCI clock.
30
MODCK[1-3]
MODCK_H-
The “low” values are the minimum allowable frequencies for a given clock mode. The minimum bus frequency
guarantees the required minimum CPU operating frequency. Minimum CPU frequency is determined by the clock
mode. For modes with a CPU multiplication factor
shown in the table. For modes with a CPU multiplication factor
The “high” values are for the purpose of illustration only. Users must select a mode and input bus frequency so
that the resulting configuration does not exceed the frequency rating of the user’s device.
PCI_MODCK determines the PCI clock frequency range. Refer to Table 15 for higher range configurations.
MODCK_H = hard reset configuration word [28–31] (refer to Section 5.4 in the MPC8260 User’s Manual).
MODCK[1-3] = three hardware configuration pins.
CPM multiplication factor = CPM clock/bus clock
CPU multiplication factor = Core PLL multiplication factor
1101_001
1101_010
1101_011
1101_100
1101_101
1101_110
1110_000
1110_001
1110_010
1110_011
1110_100
1100_000
1100_001
1100_010
Mode
Table 16. Clock Configurations for PCI Host Mode (PCI_MODCK=1)
3
PCI Agent Mode
Low
71.4 100.0
62.5 100.0
55.6 100.0
50.0 100.0
62.5 125.0
62.5 125.0
71.4 100.0
62.5 100.0
55.6 100.0
50.0 100.0
50.0 100.0
Bus Clock
(MHz)
MPC8272 PowerQUICC II™ Family Hardware Specifications
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
High
Freescale Semiconductor, Inc.
Multiplication
For More Information On This Product,
Factor
CPM
2.5
2.5
2.5
2.5
2
2
3
3
3
3
3
4
Go to: www.freescale.com
178.6 250.0
156.3 250.0
138.9 250.0
125.0 250.0
125.0 250.0
125.0 250.0
214.3 300.0
187.5 300.0
166.7 300.0
150.0 300.0
150.0 300.0
CPM Clock
Low
(MHz)
3, the minimum CPU frequency is 125 MHz or 150 MHz, as
High
Reserved
Reserved
Reserved
Multiplication
Factor
3.5, the minimum CPU frequency is 250 MHz.
CPU
3.5
4.5
3.5
4.5
5.5
4
5
3
4
4
5
5
250.0 350.0
250.0 400.0
250.0 450.0
250.0 500.0
187.5 375.0
250.0 500.0
250.0 350.0
250.0 400.0
250.0 450.0
250.0 500.0
275.0 550.0
Low
CPU Clock
(MHz)
High
1, 2
Division
(continued)
Factor
PCI
5
5
5
5
5
5
6
6
6
6
6
MOTOROLA
Low
35.7
31.3
27.8
25.0
25.0
25.0
35.7
31.3
27.8
25.0
25.0
PCI Clock
(MHz)
High
50.0
50.0
50.0
50.0
50.0
50.0
50.0
50.0
50.0
50.0
50.0