Example Of The Autotransmit Mode With Dma Support; Read Cycle In The Autotransmit Mode - Texas Instruments OMAP5910 Reference Manual

MicroWire Interface
Figure 4.

Read Cycle in the Autotransmit Mode

WIRE_NCS
UWIRE_SCCLK
UWIRE_SDO
UWIRE_SDI
1.6

Example of the Autotransmit Mode With DMA Support

24
MicroWire Interface
11) Release the autotransmit mode: SR5 = AUTO_TX_EN: 0.
12) END
The corresponding behavior of the serial interface is described in Figure 4.
A6 A5 A4 A3
The autotransmit mode and DMA mode are controlled by the setup register 5
(SR5). The following example configures the MicroWire for a 16-bit write
access on the CS1 with the serial clock out not inverted, the CS auto toggle
enabled, the DMA request enabled, and the interrupt disabled:
1) Set up and enable the DMA channel.
2) Program the configuration registers SR1, SR3, and SR4.
3) Check the CSRB status to ensure that the peripheral is ready to receive
(low).
4) Program the control and status register (CSR) as follows:
NB_BITS_RD = 0
J
NB_BITS_WR = 16
J
INDEX = 00
J
CS_CMD: = 1
J
START = 0
J
5) Write to the setup register 5 (SR5) to configure and initiate the transfer:
DMA_TX_EN = 1
J
IT_EN = 0
J
AUTO_TX_EN = 1
J
CS_TOGGLE_TX_EN = 1 (In AUTO TX mode, setting the
J
DMA_TX_EN bit to 1 starts the transfer)
A2 A1 A0
D4 D3 D2 D1 D0
SPRU686