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MODOSC
MODOSC_REQEN
MODOSC_REQ
MODCLK
Unconditonal MODOSC
requests.
EN
DCO
DCORSEL
DCOCLK
EN
ACLK Enable Logic
OSCOFF
ACLK_REQEN
ACLK_REQ
3
000
001
010
011
100
101
110
111
SELA
3
ACLK
1
0
3
Divider
DIVA
EN
MCLK Enable Logic
CPUOFF
MCLK_REQEN
MCLK_REQ
3
000
001
010
011
100
101
110
111
3
SELM
MCLK
1
0
3
Divider
DIVM
EN
SMCLK Enable Logic
SMCLKOFF
3
SMCLK_REQEN
SMCLK_REQ
3
000
001
010
011
100
101
110
111
SELS
SMCLK
1
0
3
Divider
DIVS
EN
/1/2/4/8/16/32
/1/2/4/8/16/32
/1/2/4/8/16/32
VLOCLK
VLO
XT2CLK
XT2
XT2IN
XT2OUT
XT2DRIVE
XT2BYPASS
XT2 Fault
Detection
0
1
1
0
XT1CLK
XIN
XOUT
LF
XT1DRIVE
XT1BYPASS
XT1 Fault
Detection
0
1
1
0
HF
XTS
XT1
2
2
XT1CLK
Optional module
1
0
5.3, 6.7, 8 MHz
16, 20, 24 MHz
†
DCOFSEL
2
† Not available on all devices
Clock System Introduction
Figure 3-1. Clock System Block Diagram
72
Clock System (CS)
SLAU272C – May 2011 – Revised November 2013
Copyright © 2011–2013, Texas Instruments Incorporated