554
SAM4CP [DATASHEET]
43051E–ATPL–08/14
30.18.7 PMC Clock Generator Main Oscillator Register
Name:
CKGR_MOR
Address:
0x400E0420
Access:
Read/Write
This register can only be written if the WPEN bit is cleared in
“PMC Write Protection Mode Register”
.
MOSCXTEN: Main Crystal Oscillator Enable
A crystal must be connected between XIN and XOUT.
0 = The Main Crystal Oscillator is disabled.
1 = The Main Crystal Oscillator is enabled. MOSCXTBY must be set to 0.
When MOSCXTEN is set, the MOSCXTS flag is set once the Main Crystal Oscillator start-up time is achieved.
MOSCXTBY: Main Crystal Oscillator Bypass
0 = No effect.
1 = The Main Crystal Oscillator is bypassed. MOSCXTEN must be set to 0. An external clock must be connected on XIN.
When MOSCXTBY is set, the MOSCXTS flag in PMC_SR is automatically set.
Clearing MOSCXTEN and MOSCXTBY bits resets the MOSCXTS flag.
Note:
When the Main Crystal Oscillator Bypass is disabled (MOSCXTBY=0), the MOSCXTS flag must be read at 0 in PMC_SR
before enabling the main crystal oscillator (MOSCXTEN=1).
WAITMODE: Wait Mode Command
0 = No effect.
1 = Puts the device in Wait Mode.
Note:
The WAITMODE bit is write-only.
MOSCRCEN: Main On-Chip RC Oscillator Enable
0 = The Main On-Chip RC Oscillator is disabled.
1 = The Main On-Chip RC Oscillator is enabled.
When MOSCRCEN is set, the MOSCRCS flag is set once the Main On-Chip RC Oscillator start-up time is achieved.
31
–
30
–
29
–
28
–
27
–
26
25
24
XT32KFME
CFDEN
MOSCSEL
23
22
21
20
19
18
17
16
KEY
15
14
13
12
11
10
9
8
MOSCXTST
7
–
6
5
4
3
2
1
0
MOSCRCF
MOSCRCEN
WAITMODE
MOSCXTBY
MOSCXTEN