Datasheet

28.8.6 External Multipurpose Crystal Oscillator Control
Name: XOSCCTRL
Offset: 0x14 + n*0x04 [n=0..1]
Reset: 0x00000080
Property: PAC Write-Protection
Bit 31 30 29 28 27 26 25 24
CFDPRESC[3:0]
Access
R/W R/W R/W R/W
Reset 0 0 0 0
Bit 23 22 21 20 19 18 17 16
STARTUP[3:0] SWBEN CFDEN
Access
R/W R/W R/W R/W R/W R/W
Reset 0 0 0 0 0 0
Bit 15 14 13 12 11 10 9 8
ENALC IMULT[3:0] IPTAT[1:0] LOWBUFGAIN
Access
R/W R/W R/W R/W R/W R/W R/W R/W
Reset 0 0 0 0 0 0 0 0
Bit 7 6 5 4 3 2 1 0
ONDEMAND RUNSTDBY XTALEN ENABLE
Access
R/W R/W R/W R/W
Reset 1 0 0 0
Bits 27:24 – CFDPRESC[3:0] Clock Failure Detector Prescaler
These bits select the prescaler for the clock failure detector.
The DFLL48 oscillator is used to clock the CFD prescaler.
The CFD safe clock frequency is the DFLL48 frequency divided by 2^CFDPRESC.
Bits 23:20 – STARTUP[3:0] Start-Up Time
These bits select start-up time for the oscillator XOSCn according to the table below.
The OSCULP32K oscillator is used to clock the start-up counter.
Table 28-6. Start-UpTime for External Multipurpose Crystal Oscillator
STARTUP[3:0] Number of
OSCULP32K Clock
Cycles
Number of XOSC
Clock Cycles
Approximate
Equivalent Time(
0x0 1 3 31µs
0x1 2 3 61μs
0x2 4 3 122μs
0x3 8 3 244μs
0x4 16 3 488μs
0x5 32 3 977μs
SAM D5x/E5x Family Data Sheet
OSCCTRL – Oscillators Controller
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 795