sx126x.c具体内容

`sx126x.c` 是 SX126x 芯片驱动的具体实现代码，主要包括对 SX126x 芯片进行初始化、配置、发送和接收等操作的函数。

以下是 `sx126x.c` 的主要内容：

1. 宏定义和数据结构

定义了一些宏和数据结构，用于方便进行配置、控制和数据传输等操作。例如：

// 定义了一些寄存器地址的宏
#define SX126X_REG_OPMODE                       ( 0x01U )
#define SX126X_REG_MODEM_CONFIG1                ( 0x1DU )
#define SX126X_REG_MODEM_CONFIG2                ( 0x1EU )
#define SX126X_REG_MODEM_CONFIG3                ( 0x26U )
#define SX126X_REG_PREAMBLE_LENGTH_MSB          ( 0x20U )
#define SX126X_REG_PREAMBLE_LENGTH_LSB          ( 0x21U )

// 定义了一些数据结构，用于方便进行配置和数据传输等操作
typedef enum
{
    SX126X_MODE_RX = 0x00,
    SX126X_MODE_TX = 0x01,
    SX126X_MODE_CAD = 0x02
} sx126x_mode_t;

typedef struct sx126x_s
{
    spi_device_handle_t spi_device;
    gpio_num_t cs_pin;
    gpio_num_t busy_pin;
    sx126x_mode_t mode;
    bool packet_crc_on;
    uint32_t frequency;
    uint8_t tx_power;
    bool lora;
    uint8_t bandwidth;
    uint8_t spreading_factor;
    uint8_t coding_rate;
    uint16_t preamble_length;
    uint8_t payload_len;
    uint8_t payload[256];
} sx126x_t;

2. SPI通信函数

定义了一些 SPI 通信函数，用于与 SX126x 芯片进行数据传输。例如：

// SPI 读写函数
static int sx126x_spi_write_read(const sx126x_t* sx126x, const uint8_t* tx_buf, uint8_t* rx_buf, size_t len)
{
    spi_transaction_t trans = {
        .flags = SPI_TRANS_USE_TXDATA | SPI_TRANS_USE_RXDATA,
        .length = 8 * len,
        .tx_data = tx_buf,
        .rx_data = rx_buf,
        .user = (void*)sx126x->cs_pin
    };
    return spi_device_transmit(sx126x->spi_device, &trans);
}

// SPI 写函数
static int sx126x_spi_write(const sx126x_t* sx126x, const uint8_t* tx_buf, size_t len)
{
    spi_transaction_t trans = {
        .flags = SPI_TRANS_USE_TXDATA,
        .length = 8 * len,
        .tx_data = tx_buf,
        .user = (void*)sx126x->cs_pin
    };
    return spi_device_transmit(sx126x->spi_device, &trans);
}

3. 初始化函数

定义了初始化函数 `sx126x_init()`，用于初始化 SX126x 芯片。包括设置 SPI 通信参数、复位 SX126x 芯片、等待芯片初始化完成等操作。例如：

void sx126x_init(sx126x_t* sx126x)
{
    // 设置 SPI 通信参数
    spi_bus_config_t spi_bus_config = {
        .miso_io_num = SX126X_MISO_PIN,
        .mosi_io_num = SX126X_MOSI_PIN,
        .sclk_io_num = SX126X_SCK_PIN,
        .quadwp_io_num = -1,
        .quadhd_io_num = -1,
        .max_transfer_sz = 0
    };
    spi_device_interface_config_t spi_device_config = {
        .clock_speed_hz = 1 * 1000 * 1000,
        .mode = 0,
        .spics_io_num = sx126x->cs_pin,
        .queue_size = 1
    };
    spi_bus_initialize(SPI_HOST, &spi_bus_config, 0);
    spi_bus_add_device(SPI_HOST, &spi_device_config, &sx126x->spi_device);

    // 复位 SX126x 芯片
    gpio_set_level(sx126x->cs_pin, 1);
    gpio_set_direction(sx126x->cs_pin, GPIO_MODE_OUTPUT);
    gpio_set_direction(sx126x->busy_pin, GPIO_MODE_INPUT);
    gpio_set_pull_mode(sx126x->busy_pin, GPIO_PULLUP_ONLY);
    sx126x_reset(sx126x);
    sx126x_wakeup(sx126x);

    // 等待芯片初始化完成
    while (!sx126x_is_in_sleep_mode(sx126x))
    {
        vTaskDelay(10 / portTICK_PERIOD_MS);
    }
}

4. 接收和发送函数

定义了接收和发送函数，用于接收和发送数据。例如：

// 接收函数
void sx126x_receive(sx126x_t* sx126x)
{
    sx126x_set_rx(sx126x, sx126x->frequency);
    sx126x->mode = SX126X_MODE_RX;
}

// 发送函数
void sx126x_send(sx126x_t* sx126x)
{
    sx126x_set_tx(sx126x, sx126x->frequency);
    sx126x->mode = SX126X_MODE_TX;
    sx126x_write_payload(sx126x, sx126x->payload, sx126x->payload_len);
}

5. 常用配置函数

定义了一些常用的配置函数，用于配置 SX126x 芯片的参数，例如设置频率、发射功率、带宽、扩频因子、编码率、CRC 校验等。例如：

// 设置频率
void sx126x_set_frequency(sx126x_t* sx126x, uint32_t frequency)
{
    sx126x_set_standby(sx126x);
    sx126x_set_rf_frequency(sx126x, frequency);
    sx126x->frequency = frequency;
}

// 设置发射功率
void sx126x_set_tx_power(sx126x_t* sx126x, uint8_t power)
{
    sx126x_set_tx_power_config(sx126x, power, SX126X_PA_CONFIG_SX1261);
    sx126x->tx_power = power;
}

// 设置带宽、扩频因子、编码率
void sx126x_set_lora_parameters(sx126x_t* sx126x, uint8_t bandwidth, uint8_t spreading_factor, uint8_t coding_rate)
{
    sx126x_set_lora_mod_params(sx126x, bandwidth, spreading_factor, coding_rate);
    sx126x->bandwidth = bandwidth;
    sx126x->spreading_factor = spreading_factor;
    sx126x->coding_rate = coding_rate;
}

// 设置 CRC 校验
void sx126x_set_packet_crc_on(sx126x_t* sx126x, bool on)
{
    sx126x_set_packet_params(sx126x, sx126x->preamble_length, on, SX126X_VARIABLE_LENGTH, SX126X_CRC_2_BYTES_INV);
    sx126x->packet_crc_on = on;
}

6. CAD 函数

定义了 CAD 函数，用于进行信道活动检测。例如：

// 设置 CAD 模式
void sx126x_set_cad_mode(sx126x_t* sx126x)
{
    sx126x_set_standby(sx126x);
    sx126x_set_cad(sx126x);
    sx126x->mode = SX126X_MODE_CAD;
}

// 开始 CAD 操作
void sx126x_start_cad(sx126x_t* sx126x)
{
    sx126x_set_cad(sx126x);
    sx126x_set_dio_irq_params(sx126x, SX126X_IRQ_CAD_DONE | SX126X_IRQ_CAD_ACTIVITY_DETECTED, SX126X_IRQ_CAD_DONE | SX126X_IRQ_CAD_ACTIVITY_DETECTED, SX126X_IRQ_RADIO_NONE, SX126X_IRQ_RADIO_NONE);
    sx126x_set_rx(sx126x, sx126x->frequency);
    sx126x->mode = SX126X_MODE_CAD;
}

// 获取 CAD 操作结果
sx126x_cad_result_t sx126x_get_cad_result(sx126x_t* sx126x)
{
    uint8_t irq_status = sx126x_get_irq_status(sx126x);
    if (irq_status & SX126X_IRQ_CAD_DONE)
    {
        if (irq_status & SX126X_IRQ_CAD_ACTIVITY_DETECTED)
        {
            return SX126X_CAD_DETECTED;
        }
        else
        {
            return SX126X_CAD_IDLE;
        }
    }
    else
    {
        return SX126X_CAD_BUSY;
    }
}

以上是 `sx126x.c` 的大致内容，具体实现还需根据 SX126x 芯片的功能和硬件环境进行修改。