Texas Instruments OMAP5912 Reference Manual page 1103

SPI Master/Slave
Figure 7. DMA TX Protocol in Master Mode With CIi = 0, CEi = 0 and CPi = 0
MCU-DSP write
SPI_TX
SPI_CTRL
TSPENi
SRCLK
SPI_SR
TSPDO
TSPDI
TSDOEN
TX_ndma_req
SPI_DSR
38 Serial Interfaces
DMA write
DATA 1
RD = 0; WR = 1
1
NB+1
SPI_SR[31:0]
d0
dNB
dNB
d0
TX_EMPTY = 0 TX_EMPTY = 1
DMA write
1
NB+1
dNB d0
dNB d0
TX_EMPTY = 0
MCU-DSP write
DATA 2
RD = 0; WR = 0
SPI_SR[31:0]
TX_EMPTY = 1
SPRU760B