Datasheet

 2018 Microchip Technology Inc. Data Sheet Complete DS40002058A-page 210
ATxmega128A1U/ATxmega64A1U
Problem fix/Workaround
Configure PWM and CWCM according to the Table 39-1 on page 210.
Table 39-1. PWM and CWCM configuration.
5. AWEX PWM output after fault restarted with wrong values
When recovering from fault state, the PWM output will drive wrong values to the port for up to two CLK
PER
+ one
CLK
PER4
cycles.
Problem fix/Workaround
The following seqence can be used in Latched Mode:
a. Disable DTI outputs (Write DTICCxEN to 0)
b. Clear fault flag
c. Wait for Overflow
d. Re-enable DTI (Write DTICCxEN to 1)
e. Set pin direction to Output
This will remove the glitch, but the following period will be shorter. In Cycle-by-cycle mode the same procedure can be
followed as long as the Pattern Generation Mode is not enabled.
For Pattern generation mode, there is no workaround.
6. RTC Counter value not correctly read after sleep
If a real time counter (RTC) interrupt is used wake up the device from sleep, and bit 0 of RTC count register (CNT) has
the same value as when the device entered sleep, CNT will not be read correctly during the first prescaled RTC clock
cycle after wakeup. The value read will be the same as the value in the register was when entering sleep.
Problem fix/Workaround
Wait at least one prescaled RTC clock cycle before reading CNT.
7. RTC clock output option is non-functional
The real time counter (RTC) as clock output option is non-functional, and setting the RTCOUT bit in the clock and
event out register (CLKEVOUT ) will have no effect.
Problem fix/Workaround
None
8. USB, when receiving 1023Byte length isochronous frame, it will corrupt 1024
th
SRAM location
When USB is configured for isochronous operation and 1023Byte data payload size, the 1024
th
RAM location that is
directly after the endpoint RAM buffer will be corrupted.
Problem fix/Workaround
Allocate 1024bytes RAM buffer when using 1023 isochronous endpoint. This workaround is implemented in all USB
software and source code delivered from Microchip in the AVR Software Framework.
9. USB endpoint table is 16-byte alignment
The USB endpoint table uses 16-byte alignment, instead of 16-bit alignment.
PGM CWCM Description
0 0 PGM and CWCM disabled
0 1 PGM enabled
1 0 PGM and CWCM enabled
1 1 PGM enabled