AVR64DB28 CLKCTRL registers

The 12 registers of CLKCTRL (Clock controller), from 0x60, with their reset value and every field. The AVR64DB28 has 500 registers in 47 peripherals, one page each.

CLKCTRL Clock controller

MCLKCTRLAMCLK Control A

Address
0x60
Reset
0x00
Access
read/write
  1. 7CLKOUT
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2CLKSEL2
  7. 1CLKSEL1
  8. 0CLKSEL0
2 fields
FieldBitsWhat it does
CLKOUT7System clock out
CLKSEL2:0Clock select
  • 0 Internal high-frequency oscillator
  • 1 Internal 32.768 kHz oscillator
  • 2 32.768 kHz crystal oscillator
  • 3 External clock

MCLKCTRLBMCLK Control B

Address
0x61
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4PDIV3
  5. 3PDIV2
  6. 2PDIV1
  7. 1PDIV0
  8. 0PEN
2 fields
FieldBitsWhat it does
PDIV4:1Prescaler division
  • 0 2X
  • 1 4X
  • 2 8X
  • 3 16X
  • 4 32X
  • 5 64X
  • 8 6X
  • 9 10X
  • 10 12X
  • 11 24X
  • 12 48X
PEN0Prescaler enable

MCLKCTRLCMCLK Control C

Address
0x62
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3CFDSRC1
  6. 2CFDSRC0
  7. 1CFDTST
  8. 0CFDEN
3 fields
FieldBitsWhat it does
CFDSRC3:2Clock Failure Detect Source
  • 0 Main Clock
  • 1 XOSCHF
  • 2 XOSC32K
CFDTST1Clock Failure Detect Test
CFDEN0Clock Failure Detect Enable

MCLKINTCTRLMCLK Interrupt Control

Address
0x63
Reset
0x00
Access
read/write
  1. 7INTTYPE
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0CFD
2 fields
FieldBitsWhat it does
INTTYPE7Interrupt type
  • 0 Regular Interrupt
  • 1 NMI
CFD0Clock Failure Detect Interrupt Enable

MCLKINTFLAGSMCLK Interrupt Flags

Address
0x64
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0CFD
1 field
FieldBitsWhat it does
CFD0Clock Failure Detect Interrupt Flag

MCLKSTATUSMCLK Status

Address
0x65
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5PLLS
  4. 4EXTS
  5. 3XOSC32KS
  6. 2OSC32KS
  7. 1OSCHFS
  8. 0SOSC
6 fields
FieldBitsWhat it does
PLLS5PLL oscillator status
EXTS4External Clock status
XOSC32KS332.768 kHz Crystal Oscillator status
OSC32KS232KHz oscillator status
OSCHFS1High frequency oscillator status
SOSC0System Oscillator changing

OSCHFCTRLAOSCHF Control A

Address
0x68
Reset
0x0C
Access
read/write
  1. 7RUNSTDBY
  2. 6–
  3. 5FRQSEL3
  4. 4FRQSEL2
  5. 3FRQSEL1
  6. 2FRQSEL0
  7. 1–
  8. 0AUTOTUNE
3 fields
FieldBitsWhat it does
RUNSTDBY7Run standby
FRQSEL5:2Frequency select
  • 0 1 MHz system clock
  • 1 2 MHz system clock
  • 2 3 MHz system clock
  • 3 4 MHz system clock (default)
  • 5 8 MHz system clock
  • 6 12 MHz system clock
  • 7 16 MHz system clock
  • 8 20 MHz system clock
  • 9 24 MHz system clock
AUTOTUNE0Autotune

OSCHFTUNEOSCHF Tune

Address
0x69
Reset
0x00
Access
read/write
  1. 7TUNE7
  2. 6TUNE6
  3. 5TUNE5
  4. 4TUNE4
  5. 3TUNE3
  6. 2TUNE2
  7. 1TUNE1
  8. 0TUNE0
1 field
FieldBitsWhat it does
TUNE7:0Tune

PLLCTRLAPLL Control A

Address
0x70
Reset
0x00
Access
read/write
  1. 7RUNSTDBY
  2. 6SOURCE
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1MULFAC1
  8. 0MULFAC0
3 fields
FieldBitsWhat it does
RUNSTDBY7Run standby
SOURCE6Source
  • 0 High frequency internal oscillator as PLL source
  • 1 High frequency external clock or external high frequency oscillator as PLL source
MULFAC1:0Multiplication factor
  • 0 PLL is disabled
  • 1 2 x multiplication factor
  • 2 3 x multiplication factor

OSC32KCTRLAOSC32K Control A

Address
0x78
Reset
0x00
Access
read/write
  1. 7RUNSTDBY
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–
1 field
FieldBitsWhat it does
RUNSTDBY7Run standby

XOSC32KCTRLAXOSC32K Control A

Address
0x7C
Reset
0x00
Access
read/write
  1. 7RUNSTDBY
  2. 6–
  3. 5CSUT1
  4. 4CSUT0
  5. 3–
  6. 2SEL
  7. 1LPMODE
  8. 0ENABLE
5 fields
FieldBitsWhat it does
RUNSTDBY7Run standby
CSUT5:4Crystal startup time
  • 0 1k cycles
  • 1 16k cycles
  • 2 32k cycles
  • 3 64k cycles
SEL2Select
LPMODE1Low power mode
ENABLE0Enable

XOSCHFCTRLAXOSC High-Frequency Control A

Address
0x80
Reset
0x00
Access
read/write
  1. 7RUNSTBY
  2. 6–
  3. 5CSUTHF1
  4. 4CSUTHF0
  5. 3FRQRANGE1
  6. 2FRQRANGE0
  7. 1SELHF
  8. 0ENABLE
5 fields
FieldBitsWhat it does
RUNSTBY7Run Standby
CSUTHF5:4Start-up Time Select
  • 0 256 XOSCHF cycles
  • 1 1K XOSCHF cycles
  • 2 4K XOSCHF cycles
FRQRANGE3:2Frequency Range
  • 0 Max 8 MHz XTAL Frequency
  • 1 Max 16 MHz XTAL Frequency
  • 2 Max 24 MHz XTAL Frequency
  • 3 Max 32 MHz XTAL Frequency
SELHF1External Source Select
  • 0 External Crystal
  • 1 External clock on XTALHF1 pin
ENABLE0Enable