Datasheet
95
32059L–AVR32–01/2012
AT32UC3B
8. SPI bad serial clock generation on 2nd chip_select when SCBR=1, CPOL=1, and
NCPHA=0
When multiple chip selects (CS) are in use, if one of the baudrates equal 1 while one
(CSRn.SCBR=1) of the others do not equal 1, and CSRn.CPOL=1 and CSRn.NCPHA=0,
then an additional pulse will be generated on SCK.
Fix/Workaround
When multiple CS are in use, if one of the baudrates equals 1, the others must also equal 1
if CSRn.CPOL=1 and CSRn.NCPHA=0.
9. SPI Glitch on RXREADY flag in slave mode when enabling the SPI or during the first
transfer
In slave mode, the SPI can generate a false RXREADY signal during enabling of the SPI or
during the first transfer.
Fix/Workaround
1. Set slave mode, set required CPOL/CPHA.
2. Enable SPI.
3. Set the polarity CPOL of the line in the opposite value of the required one.
4. Set the polarity CPOL to the required one.
5. Read the RXHOLDING register.
Transfers can now begin and RXREADY will now behave as expected.
10. SPI CSNAAT bit 2 in register CSR0...CSR3 is not available
SPI CSNAAT bit 2 in register CSR0...CSR3 is not available.
Fix/Workaround
Do not use this bit.
11. SPI disable does not work in SLAVE mode
SPI disable does not work in SLAVE mode.
Fix/Workaround
Read the last received data, then perform a software reset by writing a one to the Software
Reset bit in the Control Register (CR.SWRST).
- Power Manager
1. PLL Lock control does not work
PLL lock Control does not work.
Fix/Workaround
In PLL Control register, the bit 7 should be set in order to prevent unexpected behavior.
2. Wrong reset causes when BOD is activated
Setting the BOD enable fuse will cause the Reset Cause Register to list BOD reset as the
reset source even though the part was reset by another source.
Fix/Workaround
Do not set the BOD enable fuse, but activate the BOD as soon as your program starts.
3. System Timer mask (Bit 16) of the PM CPUMASK register is not available
System Timer mask (Bit 16) of the PM CPUMASK register is not available.
Fix/Workaround
Do not use this bit.