SAM4C_14 Datasheet, PDF (697/1303 Pages) ATMEL Corporation – Atmel | SMART ARM-based Flash MCU

Figure 33-7 shows the behavior of Transmit Data Register Empty (TDRE), Receive Data Register (RDRF) and
Transmission Register Empty (TXEMPTY) status flags within the SPI_SR during an 8-bit data transfer in Fixed
mode without the PDC involved.
Figure 33-7. Status Register Flags Behavior
1
2
3
4
5
6
7
8
SPCK
NPCS0
MOSI
(from master)
MSB
6
5
4
3
2
1
LSB
TDRE
Write in
SPI_TDR
RDRF
RDR read
MISO
(from slave)
MSB
6
5
4
3
2
1
LSB
TXEMPTY
shift register empty
SAM4C Series [DATASHEET]
Atmel-11102E-ATARM-SAM4C32-SAM4C16-SAM4C8-Datasheet_06-Oct-14
697