Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD Data Sheet
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Product codes
AT32UC3A3-XPLD
420
32072H–AVR32–10/2012
AT32UC3A3
0: The FIFO is not used in reception (only one character can be stored in the SPI).
• WDRBT: Wait Data Read Before Transfer
1: In master mode, a transfer can start only if the RDR register is empty, i.e. does not contain any unread data. This mode
prevents overrun error in reception.
0: No Effect. In master mode, a transfer can be initiated whatever the state of the RDR register is.
• MODFDIS: Mode Fault Detection
1: Mode fault detection is disabled. If the I/O controller does not have open-drain capability, mode fault detection must be
disabled for proper operation of the SPI.
0: Mode fault detection is enabled.
• PCSDEC: Chip Select Decode
0: The chip selects are directly connected to a peripheral device.
1: The four chip select lines are connected to a 4- to 16-bit decoder.
When PCSDEC equals one, up to 15 Chip Select signals can be generated with the four lines using an external 4- to 16-bit
decoder. The CSRn registers define the characteristics of the 15 chip selects according to the following rules:
CSR0 defines peripheral chip select signals 0 to 3.
CSR1 defines peripheral chip select signals 4 to 7.
CSR2 defines peripheral chip select signals 8 to 11.
CSR3 defines peripheral chip select signals 12 to 14.
• PS: Peripheral Select
1: Variable Peripheral Select.
0: Fixed Peripheral Select.
• MSTR: Master/Slave Mode
1: SPI is in master mode.
0: SPI is in slave mode.