MOTOROLA
Chapter 9. Clock Module
9-3
Block Diagram
There is also a fast wakeup option for quickly enabling the system clocks during stop
recovery. This eliminates the wakeup recovery time but at the risk of sending a potentially
unstable clock to the system. To prevent a non-locked PLL frequency overshoot when using
the fast wakeup option, change the RFD divisor to the current RFD value plus one before
entering stop mode.
In external clock mode, there are no wakeup periods for oscillator startup or PLL lock.
9.4
Block Diagram
Figure shows a block diagram of the entire clock module. The PLL block in this diagram
is expanded in detail in Figure 9-2.
.
Figure 9-1. Clock Module Block Diagram
CLKOUT
XTAL
EXTERNAL CLOCK
OSC
PLLREF
REFERENCE
CLOCK
PLL
MFD
PLLMODE
LOCEN
CLKMOD[1:0]
RSTOUT
CLKOUT
LOCKS
LOCK
LOCS
RFD[2:0]
TO RESET
MODULE
LOLRE
LOCRE
STPMD[1:0]
STOP MODE
PLLSEL
DISCLK
PLL CLOCK OUT
SCALED PLL CLOCK OUT
INTERNAL CLOCK
PLLMODE
CLKGEN
STOP MODE
INTERNAL
CLOCKS
LOCK
FWKUP
EXTAL
Summary of Contents for ColdFire MCF5281
Page 124: ...3 20 MCF5282 User s Manual MOTOROLA EMAC Instruction Set Summary ...
Page 141: ...MOTOROLA Chapter 5 Static RAM SRAM 5 5 SRAM Programming Model ...
Page 142: ...5 6 MCF5282 User s Manual MOTOROLA SRAM Programming Model ...
Page 168: ...6 26 MCF5282 User s Manual MOTOROLA Interrupts ...
Page 186: ...7 18 MCF5282 User s Manual MOTOROLA Functional Description ...
Page 228: ...9 22 MCF5282 User s Manual MOTOROLA Functional Description ...
Page 246: ...10 18 MCF5282 User s Manual MOTOROLA Low Power Wakeup Operation ...
Page 254: ...11 8 MCF5282 User s Manual MOTOROLA Memory Map and Registers ...
Page 264: ...12 10 MCF5282 User s Manual MOTOROLA Chip Select Registers ...
Page 280: ...13 16 MCF5282 User s Manual MOTOROLA Misaligned Operands ...
Page 314: ...14 34 MCF5282 User s Manual MOTOROLA MCF5282 External Signals ...
Page 339: ...MOTOROLA Chapter 15 Synchronous DRAM Controller Module 15 25 SDRAM Example ...
Page 340: ...15 26 MCF5282 User s Manual MOTOROLA SDRAM Example ...
Page 356: ...16 16 MCF5282 User s Manual MOTOROLA DMA Controller Module Functional Description ...
Page 408: ...17 52 MCF5282 User s Manual MOTOROLA Buffer Descriptors ...
Page 446: ...20 24 MCF5282 User s Manual MOTOROLA Interrupts ...
Page 474: ...22 18 MCF5282 User s Manual MOTOROLA Programming Model ...
Page 510: ...23 36 MCF5282 User s Manual MOTOROLA Operation ...
Page 526: ...24 16 MCF5282 User s Manual MOTOROLA I2C Programming Examples ...
Page 672: ...28 12 MCF5282 User s Manual MOTOROLA Functional Description ...
Page 718: ...29 46 MCF5282 User s Manual MOTOROLA Motorola Recommended BDM Pinout ...
Page 750: ...32 8 MCF5282 User s Manual MOTOROLA Ordering Information ...