How to Use MSP432P4111: Examples, Pinouts, and Specs

The MSP432P4111 is a low-power microcontroller developed by Texas Instruments. It is built around a 32-bit ARM Cortex-M4F core, which includes a floating-point unit (FPU) for efficient mathematical computations. This microcontroller is designed for high-performance applications while maintaining low energy consumption, making it ideal for battery-powered and energy-sensitive devices.

• Industrial automation and control systems
• Wearable devices and IoT applications
• Data acquisition and signal processing
• Low-power sensor nodes
• Consumer electronics requiring efficient computation and low power

The MSP432P4111 is available in a 100-pin LQFP package. Below is a summary of key pins:

Refer to the official datasheet for a complete pinout and alternate functions.

1. Power Supply: Ensure the microcontroller is powered within the operating voltage range (1.62V to 3.7V). Use decoupling capacitors (e.g., 0.1 µF) near the VCC and GND pins to stabilize the power supply.
2. Clock Configuration: The MSP432P4111 can use an internal clock or an external crystal oscillator. For precise timing, connect a crystal oscillator to the XTAL_IN and XTAL_OUT pins.
3. Programming: Use the JTAG or SWD interface to program the microcontroller. Texas Instruments provides the Code Composer Studio (CCS) IDE for development.
4. Peripherals: Configure peripherals (e.g., ADC, UART, SPI) using the driver library provided by Texas Instruments or through direct register manipulation.
5. Low-Power Modes: Utilize the low-power modes to reduce energy consumption when the microcontroller is idle.

• GPIO Configuration: Set unused GPIO pins to a low-power state to minimize current leakage.
• Debugging: Use the EnergyTrace tool in CCS to monitor power consumption during development.
• External Pull-Up/Down Resistors: For pins that require a defined state, use external pull-up or pull-down resistors.
• Bypass Capacitors: Place bypass capacitors close to the power pins to reduce noise and improve stability.

Below is an example of using the MSP432P4111 to read an analog signal and send the data to an Arduino UNO via UART.

1. Connect the MSP432P4111's UART_TX pin to the Arduino UNO's RX pin.
2. Connect the MSP432P4111's UART_RX pin to the Arduino UNO's TX pin.
3. Connect the GND pins of both devices.

#include "driverlib.h"

// UART configuration parameters
const eUSCI_UART_Config uartConfig = {
    EUSCI_A_UART_CLOCKSOURCE_SMCLK, // Clock source
    78,                             // Clock prescaler
    2,                              // First mod register
    0,                              // Second mod register
    EUSCI_A_UART_NO_PARITY,         // No parity
    EUSCI_A_UART_LSB_FIRST,         // LSB first
    EUSCI_A_UART_ONE_STOP_BIT,      // One stop bit
    EUSCI_A_UART_MODE,              // UART mode
    EUSCI_A_UART_OVERSAMPLING_BAUDRATE_GENERATION // Oversampling
};

int main(void) {
    WDT_A_holdTimer(); // Stop watchdog timer

    // Configure UART pins
    GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1,
        GPIO_PIN2 | GPIO_PIN3, GPIO_PRIMARY_MODULE_FUNCTION);

    // Initialize UART
    UART_initModule(EUSCI_A0_BASE, &uartConfig);
    UART_enableModule(EUSCI_A0_BASE);

    while (1) {
        // Send a test message
        const char message[] = "Hello from MSP432P4111!\r\n";
        for (int i = 0; i < sizeof(message) - 1; i++) {
            UART_transmitData(EUSCI_A0_BASE, message[i]);
        }
        __delay_cycles(48000000); // Delay for 1 second at 48 MHz
    }
}

void setup() {
    Serial.begin(9600); // Initialize UART at 9600 baud
}

void loop() {
    if (Serial.available()) {
        // Read and print data from MSP432P4111
        char received = Serial.read();
        Serial.print(received);
    }
}

1. Microcontroller Not Powering On

   • Ensure the power supply voltage is within the specified range (1.62V to 3.7V).
   • Check for proper connections and decoupling capacitors near the VCC and GND pins.

2. UART Communication Fails

   • Verify the baud rate and UART configuration on both devices.
   • Check the physical connections between the MSP432P4111 and the other device.

3. ADC Readings Are Inaccurate

   • Ensure the analog input voltage is within the ADC's input range.
   • Use a low-pass filter to reduce noise on the analog input signal.

4. High Power Consumption

   • Verify that unused GPIO pins are configured in a low-power state.
   • Use low-power modes when the microcontroller is idle.

Q: Can the MSP432P4111 operate without an external crystal oscillator?
A: Yes, the MSP432P4111 has an internal clock source, but an external crystal oscillator is recommended for applications requiring precise timing.

Q: What development tools are available for the MSP432P4111?
A: Texas Instruments provides Code Composer Studio (CCS) and the MSP432 Driver Library for development. Additionally, third-party tools like Keil and IAR are supported.

Q: How can I monitor power consumption during development?
A: Use the EnergyTrace tool available in Code Composer Studio to measure and optimize power usage.