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MibSPI Operation Modes
Multi-Buffer Serial Peripheral Interface (MibSPI) (SPNU217B)
11
new data is written to the slave shift register (SPIDAT0) and the slave has
been selected by the master (SPISCS is low).
If the SPIENA pin is in push-pull mode (ENABLE_HIGHZ = 0), the slave will
drive SPIENA high only if there is new data in the buffer register and the slave
is selected by the master (SPISCS is low). The slave SPI will drive the
SPIENA signal low when new data is written to the slave shift register
(SPIDAT0) and the slave is selected by the master (SPISCS is low). If the
slave is de-selected by the master (SPISCS goes high), the slave SPIENA
signal is driven low, allowing the master SPI to communicate with other slave
SPIs.
Figure 5.
MibSPI Five-Pin Option with SPIENA and SPISCS
In the master SPI (CLKMOD = 1), the SPISCS pin is configured as a
functional output. If configured as a slave SPI (CLKMOD = 0), the SPISCS
pin is configured as a functional input. A write to the master’s SPIDAT1 shift
register will automatically drive the SPISCS signal low. The master will drive
the SPISCS signal high again after transmitting the new character. If the new
data is written to the master’s SPIDAT0 shift register, the SPISCS signal will
NOT be driven low.
MibSPI five pin option
Master
Slave
(Master = 1 ; CLKMOD = 1)
(Master = 0 ; CLKMOD = 0)
SPIDAT1
SPIDAT0
MSB
LSB
MSB
LSB
Write to
SPISOMI
SPISIMO
SPISOMI
SPISIMO
SPICLK
SPICLK
SPISCS
SPISCS
Write to
Write to SPIDAT0 (SLAVE)
Write to SPIDAT1 (MASTER)
SPICLK
SPISIMO
SPISOMI
SPIENA
SPIENA
SPIENA
SPISCS
Содержание TMS470R1x
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