Clocking
Table 79 describes the clock ratio between e500 Core0 and the e500 core complex bus (CCB). This ratio
is determined by the binary value of LBCTL, LALE and LGPL2/LOE/LFRE at power up, as shown in
Table 79.
Table 79. e500 Core0 to CCB Clock Ratio
Binary Value of
LBCTL, LALE,
LGPL2/LOE/LFRE
Signals
Binary Value of
LBCTL, LALE,
LGPL2/LOE/LFRE
Signals
e500 Core0:CCB Clock Ratio
e500 Core0:CCB Clock Ratio
000
001
010
011
Reserved
Reserved
Reserved
3:2 (1.5:1)
100
101
110
111
2:1
5:2 (2.5:1)
3:1
7:2 (3.5:1)
Table 80 describes the clock ratio between e500 Core1 and the e500 core complex bus (CCB). This ratio
is determined by the binary value of LWE[0]/LBS[0]/LFWE, UART_SOUT[1], and READY_P1 signals
at power up, as shown in Table 80.
Table 80. e500 Core1 to CCB Clock Ratio
Binary Value of
LWE[0]/LBS[0]/
LFWE, UART_SOUT[1],
READY_P1 Signals
Binary Value of
LWE[0]/LBS[0]/
LFWE, UART_SOUT[1],
READY_P1 Signals
e500 Core1:CCB Clock Ratio
e500 Core1:CCB Clock Ratio
000
001
010
011
Reserved
Reserved
Reserved
3:2 (1.5:1)
100
101
110
111
2:1
5:2 (2.5:1)
3:1
7:2 (3.5:1)
19.4 DDR/DDRCLK PLL Ratio
The dual DDR memory controller complexes can be synchronous with, or asynchronous to, the CCB,
depending on configuration.
Table 81 describes the clock ratio between the DDR memory controller complexes and the DDR PLL
reference clock, DDRCLK, which is not the memory bus clock. The DDR memory controller complexes
clock frequency is equal to the DDR data rate.
When synchronous mode is selected, the memory buses are clocked at half the CCB clock rate. The default
mode of operation is for the DDR data rate for both DDR controllers to be equal to the CCB clock rate in
synchronous mode, or the resulting DDR PLL rate in asynchronous mode.
In asynchronous mode, the DDR PLL rate to DDRCLK ratios listed in Table 81 reflects the DDR data rate
to DDRCLK ratio, because the DDR PLL rate in asynchronous mode means the DDR data rate resulting
from DDR PLL output.
MPC8572E PowerQUICC III Integrated Processor Hardware Specifications, Rev. 4
120
Freescale Semiconductor
FREESCALE [ Freescale ]
