MSP432P4xx Pin Functions

FUNCTION SIGNAL NAME Pin Alt Pin PIN(PZ) ALT(PZ) SIG TYP DESCRIPTION
ADC A0 P5.5   69   I ADC analog input A0
A1 P5.4   68   I ADC analog input A1
A2 P5.3   67   I ADC analog input A2
A3 P5.2   66   I ADC analog input A3
A4 P5.1   65   I ADC analog input A4
A5 P5.0   64   I ADC analog input A5
A6 P4.7   63   I ADC analog input A6
A7 P4.6   62   I ADC analog input A7
A8 P4.5   61   I ADC analog input A8
A9 P4.4   60   I ADC analog input A9
A10 P4.3   59   I ADC analog input A10
A11 P4.2   58   I ADC analog input A11
A12 P4.1   57   I ADC analog input A12
A13 P4.0   56   I ADC analog input A13
A14 P6.1   55   I ADC analog input A14
A15 P6.0   54   I ADC analog input A15
A16 P9.1   53   I ADC analog input A16
A17 P9.0   52   I ADC analog input A17
A18 P8.7   51   I ADC analog input A18
A19 P8.6   50   I ADC analog input A19
A20 P8.5   49   I ADC analog input A20
A21 P8.4   48   I ADC analog input A21
A22 P8.3   47   I ADC analog input A22
A23 P8.2   46   I ADC analog input A23
Clock ACLK P4.2   58   O ACLK clock output
DCOR     44   DCO external resistor pin
HFXIN PJ.3   86   I Input for high-frequency crystal oscillator HFXT
HFXOUT PJ.2   85   O Output for high-frequency crystal oscillator HFXT
HSMCLK P4.4   60   O HSMCLK clock output
LFXIN PJ.0   41   I Input for low-frequency crystal oscillator LFXT
LFXOUT PJ.1   42   O Output of low-frequency crystal oscillator LFXT
MCLK P4.3   59   O MCLK clock output
Comparator C0.0 P8.1   31   I Comparator_E0 input 0
C0.1 P8.0   30   I Comparator_E0 input 1
C0.2 P7.7   29   I Comparator_E0 input 2
C0.3 P7.6   28   I Comparator_E0 input 3
C0.4 P7.5   27   I Comparator_E0 input 4
C0.5 P7.4   26   I Comparator_E0 input 5
C0.6 P10.5   25   I Comparator_E0 input 6
C0.7 P10.4   24   I Comparator_E0 input 7
C1.0 P6.7   81   I Comparator_E1 input 0
C1.1 P6.6   80   I Comparator_E1 input 1
C1.2 P6.5   79   I Comparator_E1 input 2
C1.3 P6.4   78   I Comparator_E1 input 3
C1.4 P6.3   77   I Comparator_E1 input 4
C1.5 P6.2   76   I Comparator_E1 input 5
C1.6 P5.7   71   I Comparator_E1 input 6
C1.7 P5.6   70   I Comparator_E1 input 7
LCD L0 P3.7   39   O LCD drive pin 0 for either segment or common output
L1 P3.6   38   O LCD drive pin 1 for either segment or common output
L2 P3.5   37   O LCD drive pin 2 for either segment or common output
L3 P3.4   36   O LCD drive pin 3 for either segment or common output
L4 P3.3   35   O LCD drive pin 4 for either segment or common output
L5 P3.2   34   O LCD drive pin 5 for either segment or common output
L6 P3.1   33   O LCD drive pin 6 for either segment or common output
L7 P3.0   32   O LCD drive pin 7 for either segment or common output
L8 P2.3   19   O LCD drive pin 8 for either segment or common output
L9 P2.2   18   O LCD drive pin 9 for either segment or common output
L10 P2.1   17   O LCD drive pin 10 for either segment or common output
L11 P2.0   16   O LCD drive pin 11 for either segment or common output
L12 P1.7 P4.1 11 57 O LCD drive pin 12 for either segment or common output
L13 P1.6 P4.0 10 56 O LCD drive pin 13 for either segment or common output
L14 P1.5 P6.1 9 55 O LCD drive pin 14 for either segment or common output
L15 P1.4 P6.0 8 54 O LCD drive pin 15 for either segment or common output
L16 P1.3 P9.1 7 53 O LCD drive pin 16 for either segment or common output
L17 P1.2 P9.0 6 52 O LCD drive pin 17 for either segment or common output
L18 P1.1 P8.7 5 51 O LCD drive pin 18 for either segment or common output
L19 P1.0 P8.6 4 50 O LCD drive pin 19 for either segment or common output
L20 P2.7   23   O LCD drive pin 20 for either segment or common output
L21 P2.6   22   O LCD drive pin 21 for either segment or common output
L22 P2.5   21   O LCD drive pin 22 for either segment or common output
L23 P2.4   20   O LCD drive pin 23 for either segment or common output
L24 P6.5   79   O LCD drive pin 24 for either segment or common output
L25 P6.4   78   O LCD drive pin 25 for either segment or common output
L26 P6.3   77   O LCD drive pin 26 for either segment or common output
L27 P6.2   76   O LCD drive pin 27 for either segment or common output
L28 P7.7   29   O LCD drive pin 28 for either segment or common output
L29 P7.6   28   O LCD drive pin 29 for either segment or common output
L30 P7.5   27   O LCD drive pin 30 for either segment or common output
L31 P7.4   26   O LCD drive pin 31 for either segment or common output
L32 P9.3   75   O LCD drive pin 32 for either segment or common output
L33 P9.2   74   O LCD drive pin 33 for either segment or common output
L34 P10.5   25   O LCD drive pin 34 for either segment or common output
L35 P10.4   24   O LCD drive pin 35 for either segment or common output
L36 P10.3   3   O LCD drive pin 36 for either segment or common output
L37 P10.2   2   O LCD drive pin 37 for either segment or common output
L38 P10.1   1   O LCD drive pin 38 for either segment or common output
L39 P10.0   100   O LCD drive pin 39 for either segment or common output
L40 P9.7   99   O LCD drive pin 40 for either segment or common output
L41 P9.6   98   O LCD drive pin 41 for either segment or common output
L42 P9.5   97   O LCD drive pin 42 for either segment or common output
L43 P9.4   96   O LCD drive pin 43 for either segment or common output
L44 P8.5   49   O LCD drive pin 44 for either segment or common output
L45 P8.4   48   O LCD drive pin 45 for either segment or common output
L46 P8.3   47   O LCD drive pin 46 for either segment or common output
L47 P8.2   46   O LCD drive pin 47 for either segment or common output
R03 P7.0   88   I Input port of fourth most positive analog LCD voltage V4 in external bias mode
R13 P7.1   89   I Input port of fourth most positive analog LCD voltage V3 in external bias mode
R23 P7.2   90   I Input port of fourth most positive analog LCD voltage V2 in external bias mode
Debug SWCLKTCK     95   I Serial wire clock input (SWCLK)/JTAG clock input (TCK)
SWDIOTMS     94   I/O Serial wire data input/output (SWDIO)/JTAG test mode select (TMS)
SWO PJ.5   93   O Serial wire trace output
TDI PJ.4   92   I JTAG test data input
TDO PJ.5   93   O JTAG test data output
GPIO P1.0 P1.0   4   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability
P1.1 P1.1   5   I/O General-purpose digital I/O with port interrupt and wake-up capability
P1.2 P1.2   6   I/O General-purpose digital I/O with port interrupt and wake-up capability
P1.3 P1.3   7   I/O General-purpose digital I/O with port interrupt and wake-up capability
P1.4 P1.4   8   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability
P1.5 P1.5   9   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability
P1.6 P1.6   10   I/O General-purpose digital I/O with port interrupt and wake-up capability
P1.7 P1.7   11   I/O General-purpose digital I/O with port interrupt and wake-up capability
P2.0 P2.0   16   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function. This I/O can be configured for high drive operation with a drive capability of up to 20 mA.
P2.1 P2.1   17   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function. This I/O can be configured for high drive operation with a drive capability of up to 20 mA.
P2.2 P2.2   18   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function. This I/O can be configured for high drive operation with a drive capability of up to 20 mA.
P2.3 P2.3   19   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function. This I/O can be configured for high drive operation with a drive capability of up to 20 mA.
P2.4 P2.4   20   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P2.5 P2.5   21   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P2.6 P2.6   22   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P2.7 P2.7   23   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P3.0 P3.0   32   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability, and with reconfigurable port mapping secondary function
P3.1 P3.1   33   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P3.2 P3.2   34   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P3.3 P3.3   35   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P3.4 P3.4   36   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability, and with reconfigurable port mapping secondary function
P3.5 P3.5   37   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability, and with reconfigurable port mapping secondary function
P3.6 P3.6   38   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P3.7 P3.7   39   I/O General-purpose digital I/O with port interrupt and wake-up capability and with reconfigurable port mapping secondary function
P4.0 P4.0   56   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.1 P4.1   57   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.2 P4.2   58   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.3 P4.3   59   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.4 P4.4   60   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.5 P4.5   61   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.6 P4.6   62   I/O General-purpose digital I/O with port interrupt and wake-up capability
P4.7 P4.7   63   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.0 P5.0   64   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.1 P5.1   65   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.2 P5.2   66   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.3 P5.3   67   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.4 P5.4   68   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.5 P5.5   69   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.6 P5.6   70   I/O General-purpose digital I/O with port interrupt and wake-up capability
P5.7 P5.7   71   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.0 P6.0   54   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.1 P6.1   55   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.2 P6.2   76   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.3 P6.3   77   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.4 P6.4   78   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.5 P6.5   79   I/O General-purpose digital I/O with port interrupt and wake-up capability
P6.6 P6.6   80   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability
P6.7 P6.7   81   I/O General-purpose digital I/O with port interrupt, wake-up, and glitch filtering capability
P7.0 P7.0   88   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.1 P7.1   89   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.2 P7.2   90   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.3 P7.3   91   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.4 P7.4   26   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.5 P7.5   27   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.6 P7.6   28   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P7.7 P7.7   29   I/O General-purpose digital I/O with reconfigurable port mapping secondary function (RD)
P8.0 P8.0   30   I/O General-purpose digital I/O
P8.1 P8.1   31   I/O General-purpose digital I/O
P8.2 P8.2   46   I/O General-purpose digital I/O
P8.3 P8.3   47   I/O General-purpose digital I/O
P8.4 P8.4   48   I/O General-purpose digital I/O
P8.5 P8.5   49   I/O General-purpose digital I/O
P8.6 P8.6   50   I/O General-purpose digital I/O
P8.7 P8.7   51   I/O General-purpose digital I/O
P9.0 P9.0   52   I/O General-purpose digital I/O
P9.1 P9.1   53   I/O General-purpose digital I/O
P9.2 P9.2   74   I/O General-purpose digital I/O
P9.3 P9.3   75   I/O General-purpose digital I/O
P9.4 P9.4   96   I/O General-purpose digital I/O
P9.5 P9.5   97   I/O General-purpose digital I/O
P9.6 P9.6   98   I/O General-purpose digital I/O
P9.7 P9.7   99   I/O General-purpose digital I/O
P10.0 P10.0   100   I/O General-purpose digital I/O
P10.1 P10.1   1   I/O General-purpose digital I/O
P10.2 P10.2   2   I/O General-purpose digital I/O
P10.3 P10.3   3   I/O General-purpose digital I/O
P10.4 P10.4   24   I/O General-purpose digital I/O
P10.5 P10.5   25   I/O General-purpose digital I/O
PJ.0 PJ.0   41   I/O General-purpose digital I/O
PJ.1 PJ.1   42   I/O General-purpose digital I/O
PJ.2 PJ.2   85   I/O General-purpose digital I/O
PJ.3 PJ.3   86   I/O General-purpose digital I/O
PJ.4 PJ.4   92   I/O General-purpose digital I/O
PJ.5 PJ.5   93   I/O General-purpose digital I/O
I2C UCB0SCL P1.7   11   I/O I2C clock in eUSCI_B0 I2C mode
UCB0SDA P1.6   10   I/O I2C data in eUSCI_B0 I2C mode
UCB1SCL P6.5   79   I/O I2C clock in eUSCI_B1 I2C mode
UCB1SDA P6.4   78   I/O I2C data in eUSCI_B1 I2C mode
UCB3SCL P10.3   3   I/O I2C clock in eUSCI_B3 I2C mode
UCB3SCL P6.7   81   I/O I2C clock in eUSCI_B3 I2C mode
UCB3SDA P10.2   2   I/O I2C data in eUSCI_B3 I2C mode
UCB3SDA P6.6   80   I/O I2C data in eUSCI_B3 I2C mode
Port Mapper PM_C0OUT P7.1   89   O Default mapping: Comparator_E0 output
PM_C1OUT P7.2   90   O Default mapping: Comparator_E1 output
PM_DMAE0 P7.0   88   I Default mapping: DMA external trigger input
PM_SMCLK P7.0   88   O Default mapping: SMCLK clock output
PM_TA0.0 P7.3   91   I/O Default mapping: TA0 CCR0 capture: CCI0A input, compare: Out0
PM_TA0.1 P2.4   20   I/O Default mapping: TA0 CCR1 capture: CCI1A input, compare: Out1
PM_TA0.2 P2.5   21   I/O Default mapping: TA0 CCR2 capture: CCI2A input, compare: Out2
PM_TA0.3 P2.6   22   I/O Default mapping: TA0 CCR3 capture: CCI3A input, compare: Out3
PM_TA0.4 P2.7   23   I/O Default mapping: TA0 CCR4 capture: CCI4A input, compare: Out4
PM_TA0CLK P7.1   89   I Default mapping: TA0 input clock
PM_TA1.2 P7.6   28   I/O Default mapping: TA1 CCR2 capture: CCI2A input, compare: Out2
PM_TA1.3 P7.5   27   I/O Default mapping: TA1 CCR3 capture: CCI3A input, compare: Out3
PM_TA1.4 P7.4   26   I/O Default mapping: TA1 CCR4 capture: CCI4A input, compare: Out4
PM_TA1CLK P7.2   90   I Default mapping: TA1 input clock
PM_UCA1CLK P2.1   17   I/O Default mapping: Clock signal input in eUSCI_A1 SPI slave mode. Clock signal output in eUSCI_A1 SPI master mode
PM_UCA1RXD P2.2   18   I Default mapping: Receive data in eUSCI_A1 UART mode
PM_UCA1SIMO P2.3   19   I/O Default mapping: Slave in, master out for eUSCI_A1 SPI mode
PM_UCA1SOMI P2.2   18   I/O Default mapping: Slave out, master in for eUSCI_A1 SPI mode
PM_UCA1STE P2.0   16   I/O Default mapping: Slave transmit enable for eUSCI_A1 SPI mode
PM_UCA1TXD P2.3   19   O Default mapping: Transmit data for eUSCI_A1 UART mode
PM_UCA2CLK P3.1   33   I/O Default mapping: Clock signal input for eUSCI_A2 SPI slave mode. Clock signal output for eUSCI_A2 SPI master mode
PM_UCA2RXD P3.2   34   I Default mapping: Receive data for eUSCI_A2 UART mode
PM_UCA2SIMO P3.3   35   I/O Default mapping: Slave in, master out for eUSCI_A2 SPI mode
PM_UCA2SOMI P3.2   34   I/O Default mapping: Slave out, master in for eUSCI_A2 SPI mode
PM_UCA2STE P3.0   32   I/O Default mapping: Slave transmit enable for eUSCI_A2 SPI mode
PM_UCA2TXD P3.3   35   O Default mapping: Transmit data for eUSCI_A2 UART mode
PM_UCB2CLK P3.5   37   I/O Default mapping: Clock signal input for eUSCI_B2 SPI slave mode. Clock signal output for eUSCI_B2 SPI master mode
PM_UCB2SCL P3.7   39   I Default mapping: I2C clock for eUSCI_B2 I2C mode
PM_UCB2SDA P3.6   38   I/O Default mapping: I2C data for eUSCI_B2 I2C mode
PM_UCB2SIMO P3.6   38   I/O Default mapping: Slave in, master out for eUSCI_B2 SPI mode
PM_UCB2SOMI P3.7   39   I/O Default mapping: Slave out, master in for eUSCI_B2 SPI mode
PM_UCB2STE P3.4   36   I/O Default mapping: Slave transmit enable for eUSCI_B2 SPI mode
Power AVCC1     45   Analog power supply
AVCC2     87   Analog power supply
AVSS1     43   Analog ground supply
AVSS2     84   Analog ground supply
AVSS3     40   Analog ground supply
DVCC1     13   Digital power supply
DVCC2     73   Digital power supply
DVSS1     15   Digital ground supply
DVSS2     72   Digital ground supply
DVSS3     82   Must be connected to ground
VCORE     12   Regulated core power supply (internal use only, no external current loading)
VSW     14   DC/DC converter switching output
RTC RTCCLK P4.3   59   O RTC_C clock calibration output
Reference VREF+ P5.6   70   O Internal shared reference voltage positive terminal
VREF- P5.7   71   O Internal shared reference voltage negative terminal
VeREF+ P5.6   70   I Positive terminal of external reference voltage to ADC
VeREF- P5.7   71   I Negative terminal of external reference voltage to ADC (recommended to connect to onboard ground)
SPI UCA0CLK P1.1   5   I/O Clock signal input for eUSCI_A0 SPI slave mode. Clock signal output for eUSCI_A0 SPI master mode
UCA0SIMO P1.3   7   I/O Slave in, master out for eUSCI_A0 SPI mode
UCA0SOMI P1.2   6   I/O Slave out, master in for eUSCI_A0 SPI mode
UCA0STE P1.0   4   I/O Slave transmit enable for eUSCI_A0 SPI mode
UCA3CLK P9.5   97   I/O Clock signal input for eUSCI_A3 SPI slave mode. Clock signal output for eUSCI_A3 SPI master mode
UCA3SIMO P9.7   99   I/O Slave in, master out for eUSCI_A3 SPI mode
UCA3SOMI P9.6   98   I/O Slave out, master in for eUSCI_A3 SPI mode
UCA3STE P9.4   96   I/O Slave transmit enable for eUSCI_A3 SPI mode
UCB0CLK P1.5   9   I/O Clock signal input for eUSCI_B0 SPI slave mode. Clock signal output for eUSCI_B0 SPI master mode
UCB0SIMO P1.6   10   I/O Slave in, master out for eUSCI_B0 SPI mode
UCB0SOMI P1.7   11   I/O Slave out, master in for eUSCI_B0 SPI mode
UCB0STE P1.4   8   I/O Slave transmit enable for eUSCI_B0 SPI mode
UCB1CLK P6.3   77   I/O Clock signal input for eUSCI_B1 SPI slave mode. Clock signal output for eUSCI_B1 SPI master mode
UCB1SIMO P6.4   78   I/O Slave in, master out for eUSCI_B1 SPI mode
UCB1SOMI P6.5   79   I/O Slave out, master in for eUSCI_B1 SPI mode
UCB1STE P6.2   76   I/O Slave transmit enable for eUSCI_B1 SPI mode
UCB3CLK P10.1 P8.1 1 31 I/O Clock signal input for eUSCI_B3 SPI slave mode. Clock signal output for eUSCI_B3 SPI master mode
UCB3SIMO P10.2 P6.6 2 80 I/O Slave in, master out for eUSCI_B3 SPI mode
UCB3SOMI P10.3 P6.7 3 81 I/O Slave out, master in for eUSCI_B3 SPI mode
UCB3STE P8.0 P10.0 30 100 I/O Slave transmit enable for eUSCI_B3 SPI mode
System NMI     83   I External nonmaskable interrupt
RSTn     83   I External reset (active low)
SVMHOUT P4.4   60   O SVMH output
Thermal QFN Pad   0 N/A   QFN package exposed thermal pad. TI recommends connection to VSS.
Timer PM_TA1.1 P7.7   29   I/O Default mapping: TA1 CCR1 capture: CCI1A input, compare: Out1
TA1.0 P8.0   30   I/O TA1 CCR0 capture: CCI0A input, compare: Out0
TA2.0 P8.1   31   I/O TA2 CCR0 capture: CCI0A input, compare: Out0
TA2.1 P5.6   70   I/O TA2 CCR1 capture: CCI1A input, compare: Out1
TA2.2 P5.7   71   I/O TA2 CCR2 capture: CCI2A input, compare: Out2
TA2.3 P6.6   80   I/O TA2 CCR3 capture: CCI3A input, compare: Out3
TA2.4 P6.7   81   I/O TA2 CCR4 capture: CCI4A input, compare: Out4
TA2CLK P4.2   58   I TA2 input clock
TA3.0 P10.4   24   I/O TA3 CCR0 capture: CCI0A input, compare: Out0
TA3.1 P10.5   25   I/O TA3 CCR1 capture: CCI1A input, compare: Out1
TA3.2 P8.2   46   I/O TA3 CCR2 capture: CCI2A input, compare: Out2
TA3.3 P9.2   74   I/O TA3 CCR3 capture: CCI3A input, compare: Out3
TA3.4 P9.3   75   I/O TA3 CCR4 capture: CCI4A input, compare: Out4
TA3CLK P8.3   47   I TA3 input clock
UART UCA0RXD P1.2   6   I Receive data for eUSCI_A0 UART mode
UCA0TXD P1.3   7   O Transmit data for eUSCI_A0 UART mode
UCA3RXD P9.6   98   I Receive data for eUSCI_A3 UART mode
UCA3TXD P9.7   99   O Transmit data for eUSCI_A3 UART mode