Clock Configuration Modes
Table 19. Clock Configurations for PCI Agent Mode (PCI_MODCK=0)
1,2
(continued)
Mode
3
MODCK_H-
MODCK[1-3]
1100_101
1100_110
1100_111
1101_000
PCI Clock
(MHz)
Low
50.0
50.0
50.0
50.0
High
66.7
66.7
66.7
66.7
CPM Clock
(MHz)
Low
High
CPU Clock
(MHz)
Low
High
Bus Clock
(MHz)
Low
High
CPM
Multiplication
Factor
4
CPU
Multiplication
Factor
5
Bus
Division
Factor
6
6
6
6
300.0 400.0
300.0 400.0
300.0 400.0
300.0 400.0
4
4.5
5
5.5
400.0 533.3
450.0 599.9
500.0 666.6
550.0 733.3
3
3
3
3
100.0 133.3
100.0 133.3
100.0 133.3
100.0 133.3
1101_001
1101_010
1101_011
1101_100
50.0
50.0
50.0
50.0
66.7
66.7
66.7
66.7
6
6
6
6
300.0 400.0
300.0 400.0
300.0 400.0
300.0 400.0
3.5
4
4.5
5
420.0 559.9
480.0 639.9
540.0 719.9
600.0 799.9
2.5
2.5
2.5
2.5
120.0 160.0
120.0 160.0
120.0 160.0
120.0 160.0
1110_000
1110_001
1110_010
1110_011
50.0
50.0
50.0
50.0
66.7
66.7
66.7
66.7
5
5
5
5
250.0 333.3
250.0 333.3
250.0 333.3
250.0 333.3
2.5
3
3.5
4
312.5 416.6
375.0 500.0
437.5 583.3
500.0 666.6
2
2
2
2
125.0 166.7
125.0 166.7
125.0 166.7
125.0 166.7
1110_100
1110_101
1110_110
1110_111
50.0
50.0
50.0
50.0
66.7
66.7
66.7
66.7
5
5
5
5
250.0 333.3
250.0 333.3
250.0 333.3
250.0 333.3
4
4.5
5
5.5
333.3 444.4
375.0 500.0
416.7 555.5
458.3 611.1
3
3
3
3
83.3 111.1
83.3 111.1
83.3 111.1
83.3 111.1
1100_000
1100_001
1100_010
1
Reserved
Reserved
Reserved
2
3
4
5
The “low” values are the minimum allowable frequencies for a given clock mode. The minimum bus frequency in a
table entry guarantees only the required minimum CPU operating frequency. 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. The minimum CPU frequency is 150 MHz for commercial temperature
devices and 175 MHz for extended temperature devices. The minimum CPM frequency is 120 MHz.
PCI_MODCK determines the PCI clock frequency range. See
for lower range configurations.
MODCK_H = hard reset configuration word [28–31] (see Section 5.4 in the SoC reference manual). MODCK[1-3] =
three hardware configuration pins.
CPM multiplication factor = CPM clock/bus clock
CPU multiplication factor = Core PLL multiplication factor
MPC8272 PowerQUICC II Family Hardware Specifications, Rev. 3
Freescale Semiconductor
39