Example Of Protocol Using The Autotransmit Mode - Texas Instruments OMAP5910 Reference Manual

MicroWire Interface
1.5

Example of Protocol Using the Autotransmit Mode

22
MicroWire Interface
5) Wait for the CSRB bit of the control and status register (CSR) to be reset.
6) Load the transmit data register (TDR) with:
D7d3...D0d3 D7d4...D0d4 D7d3...D0d3: Data for digit 3
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D7d4...D0d4: Data for digit 4
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7) Set the following fields of the control and status register (CSR):
NB_BITS_RD: 0
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NB_BITS_WR: 16 (decimal)
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INDEX: 01
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CS_CMD: 1
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START: 1
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8) Wait for the CSRB bit of the control and status register (CSR) to be reset.
9) Load the transmit data register (TDR) with:
D7...D0 x x x x x x x x x: Don't care
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D7...D0: Data for the special segment and control function
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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 to read the bit before and after every write access to the
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 autotransmit mode is controlled by the setup register 5 (SR5). The
following example configures the MicroWire for a read access on the CS0 with
the serial clock out inverted, the CS autotoggle enabled, the DMA request
disabled, and the interrupt enabled:
SPRU686