msp430 配置 lora 模块的代码

以下是一个基于 MSP430 单片机的 LoRa 模块配置示例代码，使用的是 Semtech 公司的 SX1276 模块：

#include <msp430.h>
#include <stdint.h>

#define RESET_PIN BIT0
#define DIO0_PIN BIT1
#define SPI_CLK_PIN BIT5
#define SPI_MISO_PIN BIT6
#define SPI_MOSI_PIN BIT7
#define SEL_PIN BIT4

void SPI_Write(uint8_t addr, uint8_t data)
{
    P1OUT &= ~SEL_PIN; // Set SEL pin to low to select the slave
    UCB0TXBUF = addr | 0x80; // Send the address with MSB set to 1 to indicate a write operation
    while(!(UCB0IFG & UCTXIFG)); // Wait until the transmission is complete
    UCB0TXBUF = data; // Send the data byte
    while(!(UCB0IFG & UCTXIFG)); // Wait until the transmission is complete
    P1OUT |= SEL_PIN; // Set SEL pin to high to deselect the slave
}

uint8_t SPI_Read(uint8_t addr)
{
    uint8_t data;
    P1OUT &= ~SEL_PIN; // Set SEL pin to low to select the slave
    UCB0TXBUF = addr & 0x7F; // Send the address with MSB set to 0 to indicate a read operation
    while(!(UCB0IFG & UCTXIFG)); // Wait until the transmission is complete
    UCB0TXBUF = 0; // Send a dummy byte to receive the data byte
    while(!(UCB0IFG & UCRXIFG)); // Wait until the reception is complete
    data = UCB0RXBUF; // Read the received data byte
    P1OUT |= SEL_PIN; // Set SEL pin to high to deselect the slave
    return data;
}

void LoRa_Reset()
{
    P1OUT &= ~RESET_PIN; // Set RESET pin to low to reset the module
    __delay_cycles(10000); // Wait for 10ms
    P1OUT |= RESET_PIN; // Set RESET pin to high to release the module from reset
    __delay_cycles(10000); // Wait for 10ms
}

void LoRa_Init()
{
    // Configure the SPI pins as outputs
    P1DIR |= SEL_PIN | SPI_CLK_PIN | SPI_MOSI_PIN;
    P1DIR &= ~SPI_MISO_PIN;

    // Configure the RESET and DIO0 pins as outputs
    P1DIR |= RESET_PIN | DIO0_PIN;

    // Configure the UART pins for SPI communication
    P1SEL |= SPI_CLK_PIN | SPI_MISO_PIN | SPI_MOSI_PIN;
    P1SEL2 |= SPI_CLK_PIN | SPI_MISO_PIN | SPI_MOSI_PIN;

    // Configure the USCI_B0 module for SPI communication
    UCB0CTL1 |= UCSWRST; // Reset the module
    UCB0CTL0 = UCCKPH | UCMSB | UCMST | UCSYNC; // Configure the SPI settings
    UCB0CTL1 = UCSSEL_2 | UCSWRST; // Configure the clock source for SMCLK
    UCB0BR0 = 2; // Set the clock divider to 2
    UCB0BR1 = 0;
    UCB0CTL1 &= ~UCSWRST; // Release the module from reset

    // Reset the LoRa module
    LoRa_Reset();

    // Configure the LoRa module
    SPI_Write(0x01, 0x80); // Sleep mode
    SPI_Write(0x01, 0x81); // Standby mode
    SPI_Write(0x06, 0x6C); // Set the frequency to 915MHz
    SPI_Write(0x07, 0x00); // Set the frequency deviation to 0
    SPI_Write(0x0D, 0x00); // Set the spreading factor to 6
    SPI_Write(0x0E, 0x08); // Set the bandwidth to 125kHz
    SPI_Write(0x0F, 0x0A); // Set the coding rate to 4/5
    SPI_Write(0x1D, 0x72); // Enable the CRC check
    SPI_Write(0x1E, 0x08); // Set the payload length to 8 bytes
    SPI_Write(0x26, 0x07); // Set the preamble length to 7 bytes
    SPI_Write(0x12, 0xFF); // Set the maximum output power
}

void main(void)
{
    WDTCTL = WDTPW + WDTHOLD; // Disable the watchdog timer

    LoRa_Init(); // Initialize the LoRa module

    while(1)
    {
        uint8_t data[] = {0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08};
        SPI_Write(0x0A, 0x80); // Set the module to transmit mode
        SPI_Write(0x0D, 0x0C); // Set the spreading factor to 12
        SPI_Write(0x0E, 0x08); // Set the bandwidth to 125kHz
        SPI_Write(0x1D, 0x00); // Disable the CRC check
        SPI_Write(0x1E, sizeof(data)); // Set the payload length to the size of the data
        for(uint8_t i = 0; i < sizeof(data); i++)
        {
            SPI_Write(0x00, data[i]); // Write the data to the FIFO
        }
        SPI_Write(0x0F, 0x0A); // Set the coding rate to 4/5
        SPI_Write(0x26, 0x07); // Set the preamble length to 7 bytes
        SPI_Write(0x01, 0x83); // Transmit mode
        while(!(P1IN & DIO0_PIN)); // Wait for DIO0 to go high
        SPI_Read(0x12); // Read the IRQ flags to clear them
        SPI_Write(0x01, 0x81); // Standby mode
        __delay_cycles(1000000); // Wait for 1s
    }
}

这段代码使用 MSP430 的 USCI_B0 模块进行 SPI 通信，来与 LoRa 模块进行数据的发送和接收。在这个示例中，我们将模块配置为发送模式，并发送一个长度为 8 字节的数据包。在发送完成后，我们等待接收到 LoRa 模块的中断信号（通过 DIO0 引脚），然后清除 IRQ 标志并进入待机模式，等待下一次发送。请注意，这只是一个简单的示例，实际应用中可能需要更复杂的配置和处理逻辑。