T32UC3L0128_14 Datasheet, PDF (830/852 Pages) ATMEL Corporation – Compact Single-cycle RISC Instruction Set Including DSP Instructions

35. Errata
35.1 Rev. C
35.1.1 SCIF
35.1.2 SPI
32145C–06/2013
AT32UC3L0128/256
1. The RC32K output on PA20 is not always permanently disabled
The RC32K output on PA20 may sometimes re-appear.
Fix/Workaround
Before using RC32K for other purposes, the following procedure has to be followed in order
to properly disable it:
- Run the CPU on RCSYS
- Disable the output to PA20 by writing a zero to PM.PPCR.RC32OUT
- Enable RC32K by writing a one to SCIF.RC32KCR.EN, and wait for this bit to be read as
one
- Disable RC32K by writing a zero to SCIF.RC32KCR.EN, and wait for this bit to be read as
zero.
2. PLLCOUNT value larger than zero can cause PLLEN glitch
Initializing the PLLCOUNT with a value greater than zero creates a glitch on the PLLEN sig-
nal during asynchronous wake up.
Fix/Workaround
The lock-masking mechanism for the PLL should not be used.
The PLLCOUNT field of the PLL Control Register should always be written to zero.
3. Writing 0x5A5A5A5A to the SCIF memory range will enable the SCIF UNLOCK feature
The SCIF UNLOCK feature will be enabled if the value 0x5A5A5A5A is written to any loca-
tion in the SCIF memory range.
Fix/Workaround
None.
1. SPI data transfer hangs with CSR0.CSAAT==1 and MR.MODFDIS==0
When CSR0.CSAAT==1 and mode fault detection is enabled (MR.MODFDIS==0), the SPI
module will not start a data transfer.
Fix/Workaround
Disable mode fault detection by writing a one to MR.MODFDIS.
2. Disabling SPI has no effect on the SR.TDRE bit
Disabling SPI has no effect on the SR.TDRE bit whereas the write data command is filtered
when SPI is disabled. Writing to TDR when SPI is disabled will not clear SR.TDRE. If SPI is
disabled during a PDCA transfer, the PDCA will continue to write data to TDR until its buffer
is empty, and this data will be lost.
Fix/Workaround
Disable the PDCA, add two NOPs, and disable the SPI. To continue the transfer, enable the
SPI and PDCA.
3. 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).
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