Datasheet

87
AT32UC3A
6. CPU Cycle Counter does not reset the COUNT system register on COMPARE match.
The device revision E does not reset the COUNT system register on COMPARE match. In
this revision, the COUNT register is clocked by the CPU clock, so when the CPU clock
stops, so does incrementing of COUNT.
Fix/Workaround
None.
7. Memory Protection Unit (MPU) is non functional.
Fix/Workaround
Do not use the MPU.
8. The following alternate GPIO function C are not available in revE
MACB-WOL on GPIO9 (PA09), MACB-WOL on GPIO18 (PA18), USB-USB_ID on GPIO21
(PA21), USB-USB_VBOF on GPIO22 (PA22), and all function B and C on GPIO70 to
GPIO101 (PX00 to PX39).
Fix/Workaround
Do not use these alternate B and C functions on the listed GPIO pins.
9. Clock connection table on Rev E
Here is the table of Rev E
Figure 15-1. Timer/Counter clock connections on RevE
10. Local Bus fast GPIO not available in RevE.
Fix/Workaround
Do not use on this silicon revision.
11. Spurious interrupt may corrupt core SR mode to exception
If the rules listed in the chapter `Masking interrupt requests in peripheral modules' of the
AVR32UC Technical Reference Manual are not followed, a spurious interrupt may occur. An
interrupt context will be pushed onto the stack while the core SR mode will indicate an
exception. A RETE instruction would then corrupt the stack..
Fix/Workaround
Follow the rules of the AVR32UC Technical Reference Manual. To increase software
robustness, if an exception mode is detected at the beginning of an interrupt handler,
change the stack interrupt context to an exception context and issue a RETE instruction.
Source Name Connection
Internal TIMER_CLOCK1 32 KHz Oscillator
TIMER_CLOCK2 PBA Clock / 4
TIMER_CLOCK3 PBA Clock / 8
TIMER_CLOCK4 PBA Clock / 16
TIMER_CLOCK5 PBA Clock / 32
External XC0
XC1
XC2
32058KS–AVR32–01/12