SPI Driver Implementation Steps

1. Configure SPI pin multiplexing
2. Enable peripheral clock controller for SPI
3. Disable SPI module for configuration
4. Set up control registers: configuration, clock, transmit, and receive
5. Enable SPI modulee operatoin

SPI Module Initialization

void configure_spi_module(void)
{
    // GPIO pin configuration for SPI
    initialize_gpio_pin(GPIO_PORT_E, 6, 1, 1);
    PORT_E->PIN_CONTROL[2] |= (1 << 9);
    PORT_E->PIN_CONTROL[1] |= (1 << 9);
    PORT_E->PIN_CONTROL[0] |= (1 << 9);
    
    // Disable clock for peripheral configuration
    PERIPHERAL_CLOCK_CONTROLLER->CLOCK_REGISTERS[LPSPI0_CLOCK_INDEX] = 0;
    
    // Configure peripheral clock source
    PERIPHERAL_CLOCK_CONTROLLER->CLOCK_REGISTERS[LPSPI0_CLOCK_INDEX] = 0xC6000000;
    
    // Module disable for configuration
    LPSPI0->CONTROL = 0x00000000;
    LPSPI0->INTERRUPT_ENABLE = 0x00000000;
    LPSPI0->DMA_ENABLE = 0x00000000;
    LPSPI0->CONFIG_0 = 0x00000000;
    
    // Master mode configuration settings
    LPSPI0->CONFIG_1 = 0x00000001;
    
    // Transmit command register setup
    LPSPI0->TRANSMIT_CONTROL = 0xC8000007;
    
    // Clock configuration parameters
    LPSPI0->CLOCK_CONTROL = 0x04040812;
    
    // FIFO control settings
    LPSPI0->FIFO_CONTROL = 0x00000003;
    
    // Enable module operation
    LPSPI0->CONTROL = 0x00000009;
}

SPI Data Transfer Funcsion

uint8_t spi_transfer_byte(uint8_t transmit_data)
{
    uint8_t receive_data;
    
    // Wait for transmit FIFO availability
    while ((LPSPI0->STATUS & 0x1) == 0);
    
    // Load data into transmit register
    LPSPI0->TRANSMIT_DATA = transmit_data;
    
    // Wait for receive data availability
    while (((LPSPI0->STATUS & 0x2) >> 1) == 0);
    
    // Retrieve received data
    receive_data = LPSPI0->RECEIVE_DATA;
    
    // Clear transmit data flag
    LPSPI0->STATUS |= 0x1;
    
    // Clear receive data flag
    LPSPI0->STATUS |= 0x2;
    
    return receive_data;
}