Datasheet

74
32059L–AVR32–01/2012
AT32UC3B
12.2 AT32UC3B0256, AT32UC3B0128, AT32UC3B064, AT32UC3B1256, AT32UC3B1128,
AT32UC3B164
All industrial parts labelled with -UES (for engineering samples) are revision B parts.
12.2.1 Rev I, J, K
- PWM
1. PWM channel interrupt enabling triggers an interrupt
When enabling a PWM channel that is configured with center aligned period (CALG=1), an
interrupt is signalled.
Fix/Workaround
When using center aligned mode, enable the channel and read the status before channel
interrupt is enabled.
2. PWN counter restarts at 0x0001
The PWM counter restarts at 0x0001 and not 0x0000 as specified. Because of this the first
PWM period has one more clock cycle.
Fix/Workaround
- The first period is 0x0000, 0x0001, ..., period.
- Consecutive periods are 0x0001, 0x0002, ..., period.
3. PWM update period to a 0 value does not work
It is impossible to update a period equal to 0 by the using the PWM update register
(PWM_CUPD).
Fix/Workaround
Do not update the PWM_CUPD register with a value equal to 0.
4. SPI
5. SPI Slave / PDCA transfer: no TX UNDERRUN flag
There is no TX UNDERRUN flag available, therefore in SPI slave mode, there is no way to
be informed of a character lost in transmission.
Fix/Workaround
For PDCA transfer: none.
6. 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.
7. 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.