Example Of Protocol Using Autotransmit Mode - Texas Instruments OMAP5912 Reference Manual

3.5

Example of Protocol Using Autotransmit Mode

SPRU760B
10) Set the following fields of the control and status register (CSR):
NB_BITS_RD: 0
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NB_BITS_WR: 8 (decimal)
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INDEX: 01
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CS_CMD: 1
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START: 1
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11) Wait for CSRB to go low, which indicates the CSR is ready to receive new
data. It is advised that you read the bit before and after every write access
to CSR to check the status.
12) Set the following fields of the control and status register (CSR):
INDEX: 01
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CS_CMD: 0
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START: 0
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The setup 5 register (SR5) controls the autotransmit mode. The following
example configures µWire for a read access on CS0 with serial clock out
inverted, CS autotoggle enabled, DMA request disabled, and interrupt
enabled:
1) SR5 = DMA_TX_EN: 0
IT_EN: 1
AUTO_TX_EN: 1
CS_TOGGLE_TX_EN: 1
2) SR1 = CS0_EDGE_RD: 0
CS0_EDGE_WR: 1
CS0CS_LVL: 0
CS0_FREQ: 00
CS0_CHK: 1
Note:
Data out is latched on the falling edge of the serial clock. Data in is sampled
on the rising edge.
MicroWire Interface
Serial Interfaces 111