SAM4L Datasheet, PDF (111/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

10.7.2 CPU Clock Select
Name:
CPUSEL
Access Type:
Read/Write
Offset:
0x004
Reset Value:
0x00000000
ATSAM4L4/L2
31
30
29
28
27
26
25
24
-
-
-
-
-
-
-
-
23
22
21
20
19
18
17
16
-
-
-
-
-
-
-
-
15
14
13
12
11
10
9
8
-
-
-
-
-
-
-
-
7
6
5
4
3
2
1
0
CPUDIV
-
-
-
-
CPUSEL
• CPUDIV, CPUSEL: CPU Division and Clock Select
CPUDIV = 0: CPU clock equals main clock.
CPUDIV = 1: CPU clock equals main clock divided by 2^(CPUSEL+1).
Note that if CPUDIV is written to 0, CPUSEL should also be written to 0 to ensure correct operation.
Also note that writing this register clears SR.CKRDY. The register must not be re-written until CKRDY goes high.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Refer to
Section 10.7.7 ”PM Unlock Register” on page 117 for details.
42023C–SAM–02/2013
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