ATSAM3U ATMEL [ATMEL Corporation], ATSAM3U Datasheet - Page 4

• Manufacturer Part Number: ATSAM3U
• Description: AT91 ARM Thumb-based Microcontrollers
• Manufacturer: ATMEL [ATMEL Corporation]

1.2.5
1.2.5.1
1.2.5.2
1.2.5.3
1.2.6
1.2.6.1
1.2.7
1.2.7.1
4
ATSAM3U Errata
Power Management Controller (PMC)
SAM3U Matrix (MATRIX)
PIO
PMC: SysTick does not work properly if MCK/8 is selected as clock source
PMC: Main Oscillator Crystal Failure detection not functional
PMC: Main Oscillator Frequency selection if the Main On Chip RC Oscillator is off
MATRIX: I/D default master for Flash after reset
PIO: NCS1 on PA16
The System Tick (SysTick) of the Cortex
and is configured by the CLKSOURCE bit of the SysTick CTRL register.
When setting CLKSOURCE to 0 (MCK/8), SysTick does not work properly.
Set CLKSOURCE at 1 (MCK selected as SysTick source).
This issue will be fixed in the next revision.
When the 32768 Hz Crystal Oscillator is selected as slow clock source and if the Main Oscillator
Crystal Failure detection is enabled, the CFDEV, CFDS and FOS status bits in the PMC_SR
register do not rise.
Use the Embedded 32 kHz RC Oscillator as slow clock source.
This issue will be fixed in the next revision.
When the 4/8/12 MHz RC Oscillator is off, the frequency selection (MOSCRCF in CKGR_MOR)
can not be changed. The register can be written but the modification on MOSCRCF will not be
taken into account.
Modify MOSCRCF when the 4/8/12 MHz RC Oscillator is on (MOSCRCEN =1).
This issue will be fixed in the next revision.
The I/D Cortex-M3 bus is not set as default master for the Flash after reset. There is a minor
impact in terms of performance when running the code from the Flash (about 5%).
Configure by software the I/D Cortex-M3 bus as default Master for the Flash.
This issue will be fixed in the next revision.
The chip select 1 (NCS1) of the SMC on PA16 (Peripheral B) does not work.
Workaround
Problem Fix
Workaround
Problem Fix
Workaround
Problem Fix
Workaround
Problem Fix
Workaround
®
-M3 has two sources of clock, either MCK or MCK/8
6483A–ATARM–04-Aug-09