esp32 配置sx1268的cad模式 idf框架下的完整代码

以下是ESP32与SX1268配合使用的CAD模式的完整代码，基于ESP-IDF框架：

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/spi_master.h"
#include "sx126x/sx126x.h"

#define SX1268_SPI_HOST HSPI_HOST
#define SX1268_PIN_NSS 15
#define SX1268_PIN_BUSY 4
#define SX1268_PIN_DIO1 2

spi_device_handle_t sx1268_spi;
SemaphoreHandle_t sx1268_spi_mutex;

void sx1268_spi_init()
{
    spi_bus_config_t buscfg = {
        .miso_io_num = -1,
        .mosi_io_num = 23,
        .sclk_io_num = 18,
        .quadwp_io_num = -1,
        .quadhd_io_num = -1,
        .max_transfer_sz = 0,
    };
    spi_device_interface_config_t devcfg = {
        .clock_speed_hz = 1000000,
        .mode = 0,
        .spics_io_num = SX1268_PIN_NSS,
        .queue_size = 1,
    };
    esp_err_t ret = spi_bus_initialize(SX1268_SPI_HOST, &buscfg, 1);
    assert(ret == ESP_OK);
    ret = spi_bus_add_device(SX1268_SPI_HOST, &devcfg, &sx1268_spi);
    assert(ret == ESP_OK);
    sx1268_spi_mutex = xSemaphoreCreateMutex();
    assert(sx1268_spi_mutex != NULL);
}

void sx1268_spi_write(uint8_t cmd, const uint8_t* tx_data, uint16_t tx_len)
{
    spi_transaction_t trans;
    trans.flags = SPI_TRANS_USE_TXDATA;
    trans.cmd = cmd;
    trans.addr = 0;
    trans.length = tx_len * 8;
    trans.rxlength = 0;
    trans.tx_buffer = tx_data;
    trans.rx_buffer = NULL;
    xSemaphoreTake(sx1268_spi_mutex, portMAX_DELAY);
    esp_err_t ret = spi_device_transmit(sx1268_spi, &trans);
    assert(ret == ESP_OK);
    xSemaphoreGive(sx1268_spi_mutex);
}

void sx1268_spi_read(uint8_t cmd, uint8_t* rx_data, uint16_t rx_len)
{
    spi_transaction_t trans;
    trans.flags = 0;
    trans.cmd = cmd;
    trans.addr = 0;
    trans.length = 0;
    trans.rxlength = rx_len * 8;
    trans.tx_buffer = NULL;
    trans.rx_buffer = rx_data;
    xSemaphoreTake(sx1268_spi_mutex, portMAX_DELAY);
    esp_err_t ret = spi_device_transmit(sx1268_spi, &trans);
    assert(ret == ESP_OK);
    xSemaphoreGive(sx1268_spi_mutex);
}

void sx1268_delay_ms(uint32_t delay)
{
    vTaskDelay(delay / portTICK_RATE_MS);
}

void sx1268_cad_task(void* arg)
{
    sx126x_t sx1268;
    sx1268.spi = sx1268_spi;
    sx1268.spi_write = sx1268_spi_write;
    sx1268.spi_read = sx1268_spi_read;
    sx1268.delay_ms = sx1268_delay_ms;
    sx1268.pin_nss = SX1268_PIN_NSS;
    sx1268.pin_busy = SX1268_PIN_BUSY;
    sx1268.pin_dio1 = SX1268_PIN_DIO1;
    sx126x_init(&sx1268);
    sx126x_set_standby(&sx1268, SX126X_STANDBY_RC);
    sx126x_set_reg_mode(&sx1268, SX126X_RX, SX126X_REG_MODE_CAD);
    sx126x_set_cad_params(&sx1268, 5000, 0);
    sx126x_set_rx_tx_fallback_mode(&sx1268, SX126X_RX_TX_FALLBACK_MODE_STANDBY);
    sx126x_set_rx(&sx1268, 0);
    while (1) {
        if (sx126x_cad(&sx1268) == SX126X_CAD_DETECTED) {
            printf("CAD detected!\n");
        } else {
            printf("No CAD detected.\n");
        }
        sx126x_set_rx(&sx1268, 0);
        sx126x_set_rx(&sx1268, 0);
        sx126x_set_rx(&sx1268, 0);
        sx1268_delay_ms(500);
    }
}

void app_main()
{
    sx1268_spi_init();
    xTaskCreate(sx1268_cad_task, "sx1268_cad_task", 4096, NULL, 10, NULL);
}

这个代码实现了一个简单的CAD模式例程，可以在ESP32与SX1268之间实现无线信号的探测。需要注意的是，在使用CAD模式时，需要将SX1268的工作模式设置为CAD模式，并在探测到信号后将其设置为接收模式。在这个例程中，我们使用了`sx126x_set_reg_mode()`和`sx126x_cad()`函数来实现CAD模式的开启和运行，并使用`sx126x_set_rx()`函数将SX1268切换回接收模式。