Block Diagram; Functional Description; Occs Block Diagram; Reference Clock Sources - Freescale Semiconductor 56F800 User Manual

Block Diagram

4.3 Block Diagram
EXTAL
Crystal
OSC
XTAL
Lock
Detector
Loss of
Clock
PLL

4.4 Functional Description

This section describes the clocking methods available on the 56F826/827.
Figure 4-2 illustrates the types of acceptable reference clocks. These include, from left to right:
• Crystal oscillator, uses EXTAL and XTAL pins
• External clock source, uses XTAL pin
4
Bus Interface
and
Contro
LCK
FEEDBACK
Prescaler
FREF
FOUT/2
Postscaler
Divide By [6:0]
Figure 4-1. OCCS Block Diagram
10M
External
Crystal
OSC
Source
Figure 4-2. Reference Clock Sources
56F826/827 User Manual, Rev. 3
l
Clock
PRECS
MUX
Prescaler Clk
Postscaler Clk
V /2
DDA
EXTAL
Crystal
Clock
OSC
XTAL
Bus
Interface
ZCLK
operating
clock
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