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M0A21/M0A23 Series
May 06, 2022
Page
531
of 746
Rev 1.02
M0
A21
/M
0
A
2
3
SE
RIES
TEC
H
NICAL
RE
FEREN
C
E
M
ANUAL
USCI0_CTL0
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP13
PD.7
MFP4
USCI0_DAT0
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP11
PD.5
MFP4
USCI0_DAT1
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP12
PD.6
MFP4
USCI1 SPI Basic Configurations
Clock Source Configuration
–
Enable USCI1 peripheral clock in USCI1CKEN (CLK_APBCLK1[9]).
–
Enable USCI1_SPI function on USCI1 USPI_CTL[2:0] register,
USPI_CTL[2:0]=3
’b001
Reset Configuration
–
Reset USCI1 controller in USCI0RST (SYS_IPRST2[9]).
Pin Configuration
Group
Pin Name
GPIO
MFP
USCI1
USCI1_CLK
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP15
PD.0
MFP4
USCI1_CTL0
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP18
PD.3
MFP4
USCI1_DAT0
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP16
PD.1
MFP4
USCI1_DAT1
PA.0~PA.5, PB.4~PB.7, PC.0~PC.7
MFP17
PD.2
MFP4
6.14.5 Functional Description
USCI Common Function Description
Please refer to section 6.12.4 for detailed information.
Signal Description
A device operating in Master mode controls the start and end of a data transfer, as well as the generation
of the SPI bus clock and slave select signal. The slave select signal indicates the start and the end of a
data transfer, and the master device can use it to enable the transmitting or receiving operations of
Slave device. Slave device receives the SPI bus clock and optionally a slave select signal for data
transaction. The signals for SPI communication are shown below.
SPI Mode
Receive Data
Transmit Data
Serial Bus Clock
Slave Select
Full-duplex SPI
Master
SPI_MISO
(USCIx_DAT1)
SPI_MOSI
(USCIx_DAT0)
SPI_CLK
(USCIx_CLK)
SPI_SS
(USCIx_CTL0)
Full-duplex SPI
Slave
SPI_MOSI
(USCIx_DAT0)
SPI_MISO
(USCIx_DAT1)
SPI_CLK
(USCIx_CLK)
SPI_SS
(USCIx_CTL0)