Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Ficha De Dados
Códigos do produto
ATSAM4S-WPIR-RD
671
SAM4S Series [DATASHEET]
Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14
shows the behavior of Transmit Data Register Empty (TDRE), Receive Data Register (RDRF) and
Transmission Register Empty (TXEMPTY) status flags within SPI_SR during an 8-bit data transfer in Fixed mode
without the Peripheral Data Controller involved.
Figure 33-7.
Status Register Flags Behavior
shows the behavior of Transmission Register Empty (TXEMPTY), End of RX buffer (ENDRX), End of
TX buffer (ENDTX), RX Buffer Full (RXBUFF) and TX Buffer Empty (TXBUFE) status flags within SPI_SR during
an 8-bit data transfer in Fixed mode with the Peripheral Data Controller involved. The PDC is programmed to
transfer and receive three data. The next pointer and counter are not used. The RDRF and TDRE are not shown
because these flags are managed by the PDC when using the PDC.
6
SPCK
MOSI
(from master)
MISO
(from slave)
NPCS0
MSB
MSB
LSB
LSB
6
6
5
5
4
4
3
3
2
2
1
1
1
2
3
4
5
7
8
6
RDRF
TDRE
TXEMPTY
Write in
SPI_TDR
RDR read
shift register empty