MPC8260A Motorola, MPC8260A Datasheet - Page 25

• Manufacturer Part Number: MPC8260A
• Description: Micro Processor
• Manufacturer: Motorola

MOTOROLA
1
2
3
4
MODCK[1–3]
MODCK[1–3]
MODCK_H –
1100_000
1100_010
1100_001
1010_010
1010_011
1010_100
1011_000
1011_001
1011_010
1011_011
1011_100
Input clock frequency is given only for the purpose of reference. User should set MODCK_H–MODCK_L so that
The frequency depends on the value of PCI_MODCK. If PCI_MODCK is high (logic ‘1’), the PCI frequency is
In this mode, PCI_MODCK must be “0”.
In this mode the Core PLL is bypassed (core frequency equals to bus frequency; for debug purpose only).
the resulting configuration does not exceed the frequency rating of the user’s part.
Example. If a part is rated at 266 MHz CPU, 200 MHz CPM, and 66 MHz bus, any of the following are possible
(note that the three input clock frequencies are only three of many possible input clock frequencies):
1. 66 MHz input clock, MODCK_H–MODCK_L[0111–011] (with a core multiplication factor of 4 and a CPM
2. 50 MHz input clock, MODCK_H–MODCK_L[0111–011], and PCI_MODCK = 0 (see note 2below) to
3. 40 MHz input clock, MODCK_H–MODCK_L[0010–000], and PCI_MODCK = 0 (see note 2 below) to
Note that with each of the examples, any one of several values for MODCK_H–MODCK_L could possibly be
used as long as the resulting configuration does not exceed the part’s rating.
divided by 2 (33 instead of 66 MHz, etc.).
multiplication factor of 3), and PCI_MODCK = 0 (see note 2 below). The resulting configuration equals the
part’s maximum possible frequencies of 266 MHz CPU, 200 MHz CPM, 66 MHz 60x bus, and a PCI
frequency of 66 MHz.
achieve a configuration of 200 MHz CPU, 150 MHz CPM, 50 MHz 60x bus, and a PCI frequency of 50 MHz.
achieve a configuration of 200 MHz CPU, 160 MHz CPM, 40 MHz 60x bus, and a PCI frequency of 40 MHz.
000
001
010
011
Table 18. Clock Default Configurations in PCI Agent Mode (MODCK_HI = 0000)
4
4
4
2
Input Clock
Frequency
Input Clock
100 MHz
100 MHz
100 MHz
100 MHz
100 MHz
100 MHz
100 MHz
100 MHz
Frequency
66/33 MHz
66/33 MHz
66/33 MHz
66/33 MHz
Table 17. Clock Configuration Modes in PCI Host Mode (Continued)
66MHz
66MHz
66MHz
(Bus)
(PCI)
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
3
1
MPC826xA (HiP4) Family Hardware Specifications
Multiplication
Multiplication
Factor
Factor
CPM
CPM
2.5
2.5
2.5
2.5
2.5
2.5
2/4
2/4
3/6
3/6
2
2
2
2
3
3
Frequency
Frequency
133 MHz
133 MHz
200 MHz
200 MHz
200 MHz
200 MHz
200 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
133MHz
166MHz
200MHz
CPM
CPM
Multiplication
Multiplication
Factor
Bypass
Bypass
Bypass
Factor
Core
Core
2.5
3.5
2.5
3.5
3
3
4
3
4
2
3
4
Frequency
Frequency
166 MHz
200 MHz
200 MHz
266 MHz
300 MHz
350 MHz
400 MHz
200 MHz
250 MHz
300 MHz
350 MHz
400 MHz
66MHz
66MHz
66MHz
Core
Core
Clock Configuration Modes
4
PCI Division
Bus Division
Factor
Factor
3/6
3/6
3/6
4/8
4/8
4/8
4/8
4/8
2/4
3/6
3/6
2
2
3
3
2
Frequency
Frequency
66/33 MHz
66/33 MHz
66/33 MHz
62/31 MHz
62/31 MHz
62/31 MHz
62/31 MHz
66/33 MHz
55/28 MHz
66/33 MHz
62/31MHz
1
60x Bus
66 MHz
66 MHz
66 MHz
66 MHz
PCI
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