Datasheet

17.8.5 External Multipurpose Crystal Oscillator (XOSC) Control
Name: XOSC
Offset: 0x10
Reset: 0x0080
Property: Write-Protected
Bit 15 14 13 12 11 10 9 8
STARTUP[3:0] AMPGC GAIN[2:0]
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 15:12 – STARTUP[3:0] Start-Up Time
These bits select start-up time for the oscillator according to the table below.
The OSCULP32K oscillator is used to clock the start-up counter.
STARTUP[3:0] Number of OSCULP32K
Clock Cycles
Number of XOSC
Clock Cycles
Approximate Equivalent
Time
(1)(2)(3)
0x0 1 3 31μs
0x1 2 3 61μs
0x2 4 3 122μs
0x3 8 3 244μs
0x4 16 3 488μs
0x5 32 3 977μs
0x6 64 3 1953μs
0x7 128 3 3906μs
0x8 256 3 7813μs
0x9 512 3 15625μs
0xA 1024 3 31250μs
0xB 2048 3 62500μs
0xC 4096 3 125000μs
0xD 8192 3 250000μs
0xE 16384 3 500000μs
0xF 32768 3 1000000μs
SAM D21 Family
SYSCTRL – System Controller
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40001882D-page 210