Clock Module
MCF52277 Reference Manual, Rev. 1
7-2
Freescale Semiconductor
Figure 7-1. Device Clock Connections
V2 ColdFire Core
Oscillator
EXTAL
XTAL
PCR
P
e
ri
phe
ra
l Bus Cloc
k
SRAM/Cache
FB_A16 (when
1
0
SDRAMC
FlexBus
eDMA
PIT
DMA Timers
DSPI
UART
I2C
GPIO
BDM
BOOTMOD = 10)
FB_A19 (when
BOOTMODE = 10) or
MISCCR[LIMP]
SSI
RTC_EXTAL
RTC_XTAL
CDR[S
S
ID
IV]
MISCCR
SSICLKIN
Real Time Clock
USB OTG
MISCCR[USBSRC]
USBCLKIN
CDR[LPDIV]
OUTDIV2
PCR
OUTDIV1
OUTDIV3
[PFDR]
OUTDIV5
Clock Module
f
sys
Mu
st
be 60MHz if used
as US
B
cloc
k
source
f
sys/2
Li
mp Mo
de
Cl
o
c
k
DSPI_SCK
FB_CLK
SD_CLK
SD_CLK
Notes:
1
The output frequency of OUTDIV2 must equal the output frequency of OUTDIV1
÷
2.
2
The output frequency of OUTDIV3 must equal the output frequency of OUTDIV1.
3
The output frequency of OUTDIV5 must be 60MHz if it is used as the USB clock source.
4
The SDRAMC module is 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.
5
The SDRAMC, real time clock, SSI, and USB contain some logic that uses the f
sys/2
clock, in addition
to the module-specific clock.
6
When loading boot code via the SBF, the device is clocked by the main oscillator (f
ref
).
7
The LCD controller is also given a 32 Hz clock for the cursor blink counter.
f
vco
f
ref
÷
2
LCD
Touchscreen/ADC
PWM
FlexCAN
CANCTRL[CLKSRC]
f
sys
MISCCR[RTCSRC]
O
sci
llator
[SSISRC]
Serial Boot
Facility
Summary of Contents for MCF52277
Page 22: ...MCF52277 Reference Manual Rev 1 Freescale Semiconductor xxii...
Page 32: ...MCF52277 Reference Manual Rev 0 xxxii Freescale Semiconductor...
Page 60: ...Signal Descriptions MCF52277 Reference Manual Rev 1 2 16 Freescale Semiconductor...
Page 128: ...Static RAM SRAM MCF52277 Reference Manual Rev 1 6 6 Freescale Semiconductor...
Page 140: ...Clock Module MCF52277 Reference Manual Rev 1 7 12 Freescale Semiconductor...
Page 172: ...Chip Configuration Module CCM MCF52277 Reference Manual Rev 1 9 16 Freescale Semiconductor...
Page 180: ...Serial Boot Facility SBF MCF52277 Reference Manual Rev 1 10 8 Freescale Semiconductor...
Page 188: ...Reset Controller Module MCF52277 Reference Manual Rev 1 11 8 Freescale Semiconductor...
Page 210: ...Crossbar Switch XBS MCF52277 Reference Manual Rev 1 13 8 Freescale Semiconductor...
Page 542: ...FlexCAN MCF52277 Reference Manual Rev 1 23 32 Freescale Semiconductor...
Page 724: ...UART Modules MCF52277 Reference Manual Rev 1 30 34 Freescale Semiconductor...
Page 740: ...I2 C Interface MCF52277 Reference Manual Rev 1 31 16 Freescale Semiconductor...
Page 790: ...Debug Module MCF52277 Reference Manual Rev 1 32 50 Freescale Semiconductor...