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Clock Module
8-2
Freescale Semiconductor
Figure 8-1. Device Clock Connections
Notes:
1
For the 256MAPBGA devices, FB_AD[1:0] control the multiplier during reset.
2
The output frequency of OUTDIV2 must equal the output frequency of OUTDIV1
2.
3
The output frequency of OUTDIV3 must equal the output frequency of OUTDIV1
4 or OUTDIV
8.
4
The output frequency of OUTDIV5 must be 60MHz if it is used as the USB clock source.
5
The SDRAMC, FECs, and PCI modules are disabled in limp mode. The USB controller is essentially
disabled, as well. However, it is able to capture a wake-up event to bring the device out of limp mode.
6
The SDRAMC, SSI, USB, and real time clock contain some logic that uses the f
sys/2
clock, in addition
to the module-specific clock.
7
When loading boot code via the SBF, the device is clocked by the main oscillator (f
ref
).
V4 ColdFire Core
P
e
ri
p
her
al Bus Cloc
k
SRAM/Cache
FB_AD3 (when
1
0
FlexBus
PCI
SDRAMC
eDMA
FECs
PIT
DMA Timers
DSPI
UART
I2C
GPIO
BDM
BOOTMOD = 10)
FB_AD4 (when
BOOTMODE = 10) or
MISCCR[LIMP]
SSI
ATA
RNG
CD
R[SS
IDIV]
MISCCR[SSISRC]
SSICLKIN
Real Time Clock
USB OTG
MISCCR[USBSRC]
USBCLKIN
OUTDIV2
PCR
OUTDIV1
OUTDIV3
OUTDIV4
CAU
OUTDIV5
Clock Module
f
sys
M
u
st be
60
M
H
z i
f
u
s
e
d
as US
B clo
c
k
sour
ce
f
sys/2
f
sys/(4 or 8)
DSPI_SCK
FEC
n
_TXCLK
FB_CLK
FEC
n
_RXCLK
SD_CLK
SD_CLK
FB_AD[2:0]
when
BOOTMOD = 10)
f
vco
2
CDR[LPDIV]
Limp
Mode
Cloc
k
Oscillator
EXTAL
XTAL
PCR
[PFDR]
f
ref
EXTAL32K
XTAL32K
Oscillat
or
Serial Boot
Facility
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...