Datasheet

478
SAM4S [DATASHEET]
11100E–ATARM–24-Jul-13
28.2.16.7PMC 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 Protect 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 allows resetting the MOSCXTS flag.
• WAITMODE: Wait Mode Command
0 = No effect.
1 = Enters 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
– – – – – – CFDEN MOSCSEL
23 22 21 20 19 18 17 16
KEY
15 14 13 12 11 10 9 8
MOSCXTST
76543210
– MOSCRCF MOSCRCEN WAITMODE MOSCXTBY MOSCXTEN