gd32can初始化配置及注释

以下是基于GD32F3xx系列芯片的CAN初始化配置及注释示例：

#include "gd32f3xx.h"

void CAN_Configuration(void)
{
    /* 使能CAN时钟 */
    rcu_periph_clock_enable(RCU_CAN0);

    /* 配置CAN GPIO */
    gpio_mode_set(GPIOB, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO_PIN_8 | GPIO_PIN_9);
    gpio_output_options_set(GPIOB, GPIO_OTYPE_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_8 | GPIO_PIN_9);
    gpio_af_set(GPIOB, GPIO_AF_9, GPIO_PIN_8 | GPIO_PIN_9);

    /* CAN 初始化 */
    can_deinit(CAN0);
    can_struct_para_init(&can_init_struct);

    /* 定义CAN时钟分频 */
    can_init_struct.can_frequency = 36000000U;

    /* 定义CAN位速率 */
    can_init_struct.can_tx_sjw = CAN_SJW_1TQ;
    can_init_struct.can_rx_sjw = CAN_SJW_1TQ;
    can_init_struct.can_bs1 = CAN_BS1_13TQ;
    can_init_struct.can_bs2 = CAN_BS2_2TQ;

    /* 定义过滤器 */
    can_filter_struct_para_init(&can_filter_init_struct);

    /* 过滤器模式 */
    can_filter_init_struct.can_filter_bits = CAN_FILTERBITS_32BIT;

    /* 过滤器ID */
    can_filter_init_struct.can_filter_id_high = 0x0000;
    can_filter_init_struct.can_filter_id_low = 0x0000;

    /* 过滤器掩码 */
    can_filter_init_struct.can_filter_mask_id_high = 0x0000;
    can_filter_init_struct.can_filter_mask_id_low = 0x0000;

    /* 过滤器FIFO */
    can_filter_init_struct.can_filter_fifo_number = CAN_FIFO0;

    /* 过滤器使能 */
    can_filter_enable(CAN0, 0);

    /* CAN 初始化 */
    can_init(CAN0, &can_init_struct);

    /* 配置CAN中断 */
    nvic_irq_enable(CAN0_RX0_IRQn, 0, 0);
    can_interrupt_enable(CAN0, CAN_INTEN_RFNEIE0);

    /* 启动CAN */
    can_enable(CAN0);
}

注释：

1. `rcu_periph_clock_enable(RCU_CAN0)`：使能CAN时钟
2. `gpio_mode_set(GPIOB, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO_PIN_8 | GPIO_PIN_9)`：配置CAN相关GPIO为复用功能
3. `gpio_af_set(GPIOB, GPIO_AF_9, GPIO_PIN_8 | GPIO_PIN_9)`：配置CAN相关GPIO复用功能为CAN
4. `can_deinit(CAN0)`：复位CAN控制器
5. `can_init_struct`：CAN初始化结构体，使用`can_struct_para_init`函数初始化为默认值
6. `can_init_struct.can_frequency = 36000000U`：定义CAN时钟分频
7. `can_init_struct.can_tx_sjw = CAN_SJW_1TQ`：定义CAN发送同步跳转宽度
8. `can_init_struct.can_rx_sjw = CAN_SJW_1TQ`：定义CAN接收同步跳转宽度
9. `can_init_struct.can_bs1 = CAN_BS1_13TQ`：定义CAN位时间段1的时间长度
10. `can_init_struct.can_bs2 = CAN_BS2_2TQ`：定义CAN位时间段2的时间长度
11. `can_filter_init_struct`：CAN过滤器结构体，使用`can_filter_struct_para_init`函数初始化为默认值
12. `can_filter_init_struct.can_filter_bits = CAN_FILTERBITS_32BIT`：定义过滤器模式
13. `can_filter_init_struct.can_filter_id_high`：定义过滤器ID高位
14. `can_filter_init_struct.can_filter_id_low`：定义过滤器ID低位
15. `can_filter_init_struct.can_filter_mask_id_high`：定义过滤器掩码高位
16. `can_filter_init_struct.can_filter_mask_id_low`：定义过滤器掩码低位
17. `can_filter_init_struct.can_filter_fifo_number = CAN_FIFO0`：定义过滤器FIFO
18. `can_filter_enable(CAN0, 0)`：使能过滤器
19. `can_init(CAN0, &can_init_struct)`：初始化CAN控制器
20. `nvic_irq_enable(CAN0_RX0_IRQn, 0, 0)`：使能CAN中断
21. `can_interrupt_enable(CAN0, CAN_INTEN_RFNEIE0)`：使能CAN接收中断
22. `can_enable(CAN0)`：启动CAN控制器