Техническая Спецификация для Atmel Xplained Pro Evaluation Kit ATSAMD20-XPRO ATSAMD20-XPRO
Модели
ATSAMD20-XPRO
157
Atmel | SMART SAM D20 [DATASHEET]
Atmel-42129K–SAM-D20_datasheet–06/2014
16.8.6 32kHz External Crystal Oscillator (XOSC32K) Control
Name:
XOSC32K
Offset:
0x14
Reset:
0x0080
Property:
Write-Protected
z
Bits 15:13 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to
zero when this register is written. These bits will always return zero when read.
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to
zero when this register is written. These bits will always return zero when read.
z
Bit 12 – WRTLOCK: Write Lock
This bit locks the XOSC32K register for futur writes to fix the XOSC32K configuration.
This bit locks the XOSC32K register for futur writes to fix the XOSC32K configuration.
0: The XOSC32K configuration is not locked.
1: The XOSC32K configuration is locked.
z
Bit 11 – Reserved
This bit is unused and reserved for future use. For compatibility with future devices, always write this bit to zero
when this register is written. This bit will always return zero when read.
This bit is unused and reserved for future use. For compatibility with future devices, always write this bit to zero
when this register is written. This bit will always return zero when read.
z
Bits 10:8 – STARTUP[2:0]: Oscillator Start-Up Time
These bits select the start-up time for the oscillator according to
These bits select the start-up time for the oscillator according to
The OSCULP32K oscillator is used to clock the start-up counter.
Bit
15
14
13
12
11
10
9
8
WRTLOCK
STARTUP[2:0]
Access
R
R
R
R/W
R
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
AAMPEN
EN1K
EN32K
XTALEN
ENABLE
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
Reset
1
0
0
0
0
0
0
0
Table 16-5. Start-Up Time for 32kHz External Crystal Oscillator
STARTUP[2:0]
Number of OSCULP32K
Clock Cycles
Clock Cycles
Number of XOSC32K
Clock Cycles
Clock Cycles
Approximate Equivalent Time
(OSCULP = 32.768kHz)
(OSCULP = 32.768kHz)
0x0
1
3
122µs
0x1
32
3
1068µs
0x2
2048
3
62592µs
0x3
4096
3
125092µs
0x4
16384
3
500092µs
0x5
32768
3
1000092µs
0x6
65536
3
2000092µs
0x7
131072
3
4000092µs