1 CAN配置
注：本文以GD32E508x为例，其他MCU可能有差异。
1.1 GPIO配置
CAN0、CAN1和CAN2都可以映射到多个GPIO使用，但是配置有所差异。
其中CAN0和CAN1通过配置REMAP寄存器的值来选择对应的GPIO，如下图所示：
而CAN2是通过AFIO配置，参考代码如下：
gpio_afio_port_config(AFIO_PB10_CAN2_CFG, ENABLE);
gpio_afio_port_config(AFIO_PB11_CAN2_CFG, ENABLE);
// gpio_afio_port_config(AFIO_PA9_CAN2_CFG, ENABLE);
// gpio_afio_port_config(AFIO_PA10_CAN2_CFG, ENABLE);
GPIO配置参考代码如下：
void can0_gpio_config(void)
{
/* enable CAN0 clock */
rcu_periph_clock_enable(RCU_CAN0);
rcu_periph_clock_enable(CAN0RX_CLOCK);
rcu_periph_clock_enable(RCU_AF);
/* configure CAN0 GPIO */
gpio_init(CAN0RX_PORT, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, CAN0RX_PIN);
gpio_init(CAN0TX_PORT, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, CAN0TX_PIN);
gpio_pin_remap_config(GPIO_CAN0_PARTIAL_REMAP, ENABLE);
}
void can1_gpio_config(void)
{
/* enable CAN1 clock */
rcu_periph_clock_enable(RCU_CAN1);
rcu_periph_clock_enable(CAN1RX_CLOCK);
rcu_periph_clock_enable(RCU_AF);
/* configure CAN1 GPIO */
gpio_init(CAN1RX_PORT, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, CAN1RX_PIN);
gpio_init(CAN1TX_PORT, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, CAN1TX_PIN);
gpio_pin_remap_config(GPIO_CAN1_REMAP, ENABLE);
}
void can2_gpio_config(void)
{
/* enable CAN2 clock */
rcu_periph_clock_enable(RCU_CAN2);
rcu_periph_clock_enable(CAN2RX_CLOCK);
rcu_periph_clock_enable(RCU_AF);
/* configure CAN2 GPIO */
gpio_init(CAN2RX_PORT, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, CAN2RX_PIN);
gpio_init(CAN2TX_PORT, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, CAN2TX_PIN);
gpio_afio_port_config(AFIO_PB10_CAN2_CFG, ENABLE);
gpio_afio_port_config(AFIO_PB11_CAN2_CFG, ENABLE);
}
1.2 CAN配置
CAN配置除了CAN本身的参数，还需要注意接收过滤器的分配，如下图所示，CAN0和CAN1共用28个过滤器，CAN2独立使用14个过滤器。
CAN配置参考代码如下：
void can0_config(void)
{
can_parameter_struct can_parameter;
can_fdframe_struct can_fd_parameter;
can_fd_tdc_struct can_fd_tdc_parameter;
can_filter_parameter_struct can_filter;
can_struct_para_init(CAN_INIT_STRUCT, &can_parameter);
/* initialize CAN register */
can_deinit(CAN0);
#if 0 // CAN配置
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = DISABLE;
can_parameter.rec_fifo_overwrite = DISABLE;
can_parameter.trans_fifo_order = DISABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 仲裁段波特率 = 90M / 9 / (1 + 7 + 2) = 1M */
/* configure CAN baud rate 1MBps, sample point at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ; // TSG1
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ; // TSG2
can_parameter.prescaler = 9U; // 分频系数
/* initialize CAN */
can_init(CAN0, &can_parameter);
#else // CANFD配置
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = ENABLE;
can_parameter.rec_fifo_overwrite = ENABLE;
can_parameter.trans_fifo_order = ENABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* baudrate 1Mbps, sample piont at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ;
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ;
can_parameter.prescaler = 9U;
/* initialize CAN */
can_init(CAN0, &can_parameter);
can_struct_para_init(CAN_FD_FRAME_STRUCT, &can_fd_parameter);
can_fd_parameter.fd_frame = ENABLE;
can_fd_parameter.excp_event_detect = ENABLE;
can_fd_parameter.delay_compensation = ENABLE;
can_fd_tdc_parameter.tdc_filter = 0x04U;
can_fd_tdc_parameter.tdc_mode = CAN_TDCMOD_CALC_AND_OFFSET;
can_fd_tdc_parameter.tdc_offset = 0x04U;
can_fd_parameter.p_delay_compensation = &can_fd_tdc_parameter;
can_fd_parameter.iso_bosch = CAN_FDMOD_ISO;
can_fd_parameter.esi_mode = CAN_ESIMOD_HARDWARE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 数据段波特率 = 90M / 3 / (1 + 4 + 1) = 5M */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_4TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 3; // 分频系数
/* initialize CAN-FD */
can_fd_init(CAN0, &can_fd_parameter);
#endif
/* initialize filter */
/* configure filter mode */
can_filter.filter_mode = CAN_FILTERMODE_MASK;
can_filter.filter_bits = CAN_FILTERBITS_32BIT;
/* configure filter ID */
can_filter.filter_list_high = 0x0000U;
can_filter.filter_list_low = 0x0000U;
/* configure filter mask */
can_filter.filter_mask_high = 0x0000U;
can_filter.filter_mask_low = 0x0000U;
/* select receiver fifo */
can_filter.filter_fifo_number = CAN_FIFO0;
can_filter.filter_number = 0U;
can_filter.filter_enable = ENABLE;
can_filter_init(CAN0, &can_filter);
/* configure CAN0 NVIC */
nvic_irq_enable(CAN0_RX0_IRQn, 0U, 0U);
/* enable can receive FIFO0 not empty interrupt */
can_interrupt_enable(CAN0, CAN_INTEN_RFNEIE0);
}
void can1_config(void)
{
can_parameter_struct can_parameter;
can_fdframe_struct can_fd_parameter;
can_fd_tdc_struct can_fd_tdc_parameter;
can_filter_parameter_struct can_filter;
can_struct_para_init(CAN_INIT_STRUCT, &can_parameter);
/* initialize CAN register */
can_deinit(CAN1);
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = ENABLE;
can_parameter.rec_fifo_overwrite = ENABLE;
can_parameter.trans_fifo_order = ENABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 仲裁段波特率 = 90M / 9 / (1 + 7 + 2) = 1M */
/* CAN采样率 = (1 + TSG1) / (1 + TSG1 + TSG2) = (1 + 7) / (1 + 7 + 2) = 80% */
/* baudrate 1Mbps, sample piont at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ; // TSG1
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ; // TSG2
can_parameter.prescaler = 9U; // 分频系数
/* initialize CAN */
can_init(CAN1, &can_parameter);
can_struct_para_init(CAN_FD_FRAME_STRUCT, &can_fd_parameter);
can_fd_parameter.fd_frame = ENABLE;
can_fd_parameter.excp_event_detect = ENABLE;
can_fd_parameter.delay_compensation = ENABLE;
can_fd_tdc_parameter.tdc_filter = 0x04U;
can_fd_tdc_parameter.tdc_mode = CAN_TDCMOD_CALC_AND_OFFSET;
can_fd_tdc_parameter.tdc_offset = 0x04U;
can_fd_parameter.p_delay_compensation = &can_fd_tdc_parameter;
can_fd_parameter.iso_bosch = CAN_FDMOD_ISO;
can_fd_parameter.esi_mode = CAN_ESIMOD_HARDWARE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
#if 1
/* 数据段波特率 = 90M / 3 / (1 + 4 + 1) = 5M */
/* CAN采样率 = (1 + TSG1) / (1 + TSG1 + TSG2) = (1 + 4) / (1 + 4 + 1) = 83.3% */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_4TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 3; // 分频系数
#else
/* 数据段波特率 = 90M / 2 / (1 + 6 + 2) = 5M */
/* CAN采样率 = (1 + TSG1) / (1 + TSG1 + TSG2) = (1 + 6) / (1 + 6 + 2) = 77.77% */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_7TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 2; // 分频系数
#endif
/* initialize CAN-FD */
can_fd_init(CAN1, &can_fd_parameter);
/* initialize filter */
/* configure filter mode */
can_filter.filter_mode = CAN_FILTERMODE_MASK;
can_filter.filter_bits = CAN_FILTERBITS_32BIT;
/* configure filter ID */
can_filter.filter_list_high = 0x0000U;
can_filter.filter_list_low = 0x0000U;
/* configure filter mask */
can_filter.filter_mask_high = 0x0000U;
can_filter.filter_mask_low = 0x0000U;
/* select receiver fifo */
can_filter.filter_fifo_number = CAN_FIFO1;
can_filter.filter_number = 15U; // CAN_FCTL默认定义了CAN0和CAN1过滤器序号的分配数量，CAN0使用0-13序号，CAN1使用14-27，可以通过can1_filter_start_bank()修改
can_filter.filter_enable = ENABLE;
can_filter_init(CAN1, &can_filter);
/* configure CAN1 NVIC */
nvic_irq_enable(CAN1_RX1_IRQn, 1U, 1U);
/* enable can receive FIFO0 not empty interrupt */
can_interrupt_enable(CAN1, CAN_INTEN_RFNEIE1);
}
void can2_config(void)
{
can_parameter_struct can_parameter;
can_fdframe_struct can_fd_parameter;
can_fd_tdc_struct can_fd_tdc_parameter;
can_filter_parameter_struct can_filter;
can_struct_para_init(CAN_INIT_STRUCT, &can_parameter);
/* initialize CAN register */
can_deinit(CAN2);
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = ENABLE;
can_parameter.rec_fifo_overwrite = ENABLE;
can_parameter.trans_fifo_order = ENABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* baudrate 1Mbps, sample piont at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ;
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ;
can_parameter.prescaler = 9U;
/* initialize CAN */
can_init(CAN2, &can_parameter);
can_struct_para_init(CAN_FD_FRAME_STRUCT, &can_fd_parameter);
can_fd_parameter.fd_frame = ENABLE;
can_fd_parameter.excp_event_detect = ENABLE;
can_fd_parameter.delay_compensation = ENABLE;
can_fd_tdc_parameter.tdc_filter = 0x04U;
can_fd_tdc_parameter.tdc_mode = CAN_TDCMOD_CALC_AND_OFFSET;
can_fd_tdc_parameter.tdc_offset = 0x04U;
can_fd_parameter.p_delay_compensation = &can_fd_tdc_parameter;
can_fd_parameter.iso_bosch = CAN_FDMOD_ISO;
can_fd_parameter.esi_mode = CAN_ESIMOD_HARDWARE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 数据段波特率 = 90M / 3 / (1 + 4 + 1) = 5M */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_4TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 3; // 分频系数
/* initialize CAN-FD */
can_fd_init(CAN2, &can_fd_parameter);
/* initialize filter */
/* configure filter mode */
can_filter.filter_mode = CAN_FILTERMODE_MASK;
can_filter.filter_bits = CAN_FILTERBITS_32BIT;
/* configure filter ID */
can_filter.filter_list_high = 0x0000U;
can_filter.filter_list_low = 0x0000U;
/* configure filter mask */
can_filter.filter_mask_high = 0x0000U;
can_filter.filter_mask_low = 0x0000U;
/* select receiver fifo */
can_filter.filter_fifo_number = CAN_FIFO0;
can_filter.filter_number = 1U;
can_filter.filter_enable = ENABLE;
can_filter_init(CAN2, &can_filter);
/* configure CAN2 NVIC */
nvic_irq_enable(CAN2_RX0_IRQn, 0U, 0U);
/* enable can receive FIFO0 not empty interrupt */
can_interrupt_enable(CAN2, CAN_INTEN_RFNEIE0);
}
1.3 CAN发送
CAN发送参考代码如下：
typedef struct
{
uint32_t id; // CAN ID
uint8_t frame_format; // format of frame | 0：standard | 1：extended format
uint8_t can_type; // CAN type | 0：CAN | 1：CANFD | 2：CANFD加速
uint8_t buf[64]; // CAN buf
uint8_t buf_len; // CAN buf len
} can_trasnmit_data_t;
int can_send_message(uint8_t ch, can_trasnmit_data_t can_data)
{
uint8_t i;
can_trasnmit_message_struct *can_tx_message;
switch (ch)
{
case 0:
#ifdef CAN0_ENABLE
can_tx_message = &can0_tx_message;
#endif
break;
case 1:
#ifdef CAN1_ENABLE
can_tx_message = &can1_tx_message;
#endif
break;
case 2:
#ifdef CAN2_ENABLE
can_tx_message = &can2_tx_message;
#endif
break;
default:
break;
}
if(can_data.frame_format == 0)
{// 标准帧
can_tx_message->tx_sfid = can_data.id;
}
else
{// 扩展帧
can_tx_message->tx_efid = can_data.id;
}
if(can_data.can_type == 0)
{// CAN
can_tx_message->fd_flag = 0;
can_tx_message->fd_brs = 0;
}
else if(can_data.can_type == 1)
{// CANFD
can_tx_message->fd_flag = 1;
}
else if(can_data.can_type == 2)
{// CANFD加速
can_tx_message->fd_flag = 1;
can_tx_message->fd_brs = 1;
}
can_tx_message->fd_esi = 0;
memcpy(can_tx_message->tx_data, can_data.buf, can_data.buf_len);
// CANFD模式下，数据长度只能为0 - 8, 12, 16, 20, 24, 32, 48, 64
if(can_data.buf_len > 48)
{
can_tx_message->tx_dlen = 64;
}
else if(can_data.buf_len > 32)
{
can_tx_message->tx_dlen = 48;
}
else if(can_data.buf_len > 24)
{
can_tx_message->tx_dlen = 32;
}
else if(can_data.buf_len > 20)
{
can_tx_message->tx_dlen = 24;
}
else if(can_data.buf_len > 16)
{
can_tx_message->tx_dlen = 20;
}
else if(can_data.buf_len > 12)
{
can_tx_message->tx_dlen = 16;
}
else if(can_data.buf_len > 8)
{
can_tx_message->tx_dlen = 12;
}
else
{
can_tx_message->tx_dlen = can_data.buf_len;
}
#if 1
printf("\r\n can(%d) transmit data(id: 0x%x): ", ch, can_tx_message->tx_sfid);
for(i = 0U; i < can_tx_message->tx_dlen; i++)
{
printf(" %02x", can_tx_message->tx_data);
}
#endif
/* transmit message */
if(can_message_transmit(CAN2, can_tx_message) != CAN_NOMAILBOX)
{// 发送成功
return 1;
}
return 0;
}
1.4 CAN接收
CAN接收参考代码如下：
void CAN0_RX0_IRQHandler(void)
{
/* check the receive message */
can_message_receive(CAN0, CAN_FIFO0, &can0_rx_message);
#if 1
printf("\r\n can0 receive(id=0x%X) data: ", can0_rx_message.rx_sfid);
for(int i = 0U; i < can0_rx_message.rx_dlen; i++)
{
printf(" %02x", can0_rx_message.rx_data);
}
#endif
}
void CAN1_RX1_IRQHandler(void)
{
/* check the receive message */
can_message_receive(CAN1, CAN_FIFO1, &can1_rx_message);
#if 1
printf("\r\n can1 receive(id=0x%X) data: ", can1_rx_message.rx_sfid);
for(int i = 0U; i < can1_rx_message.rx_dlen; i++)
{
printf(" %02x", can1_rx_message.rx_data);
}
#endif
}
void CAN2_RX0_IRQHandler(void)
{
/* check the receive message */
can_message_receive(CAN2, CAN_FIFO0, &can2_rx_message);
#if 1
printf("\r\n can2 receive(id=0x%X) data: ", can2_rx_message.rx_sfid);
for(int i = 0U; i < can2_rx_message.rx_dlen; i++)
{
printf(" %02x", can2_rx_message.rx_data);
}
#endif
}
2 代码编写
参考代码如下：
can.c：
#include "main.h"
#include "can.h"
#include "string.h"
// CAN收发缓存
#ifdef CAN0_ENABLE
can_trasnmit_message_struct can0_tx_message;
can_receive_message_struct can0_rx_message;
#endif
#ifdef CAN1_ENABLE
can_trasnmit_message_struct can1_tx_message;
can_receive_message_struct can1_rx_message;
#endif
#ifdef CAN2_ENABLE
can_trasnmit_message_struct can2_tx_message;
can_receive_message_struct can2_rx_message;
#endif
#ifdef CAN0_ENABLE
void can0_gpio_config(void)
{
/* enable CAN0 clock */
rcu_periph_clock_enable(RCU_CAN0);
rcu_periph_clock_enable(CAN0RX_CLOCK);
rcu_periph_clock_enable(RCU_AF);
/* configure CAN0 GPIO */
gpio_init(CAN0RX_PORT, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, CAN0RX_PIN);
gpio_init(CAN0TX_PORT, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, CAN0TX_PIN);
gpio_pin_remap_config(GPIO_CAN0_PARTIAL_REMAP, ENABLE);
}
void can0_config(void)
{
can_parameter_struct can_parameter;
can_fdframe_struct can_fd_parameter;
can_fd_tdc_struct can_fd_tdc_parameter;
can_filter_parameter_struct can_filter;
can_struct_para_init(CAN_INIT_STRUCT, &can_parameter);
/* initialize CAN register */
can_deinit(CAN0);
#if 0 // CAN配置
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = DISABLE;
can_parameter.rec_fifo_overwrite = DISABLE;
can_parameter.trans_fifo_order = DISABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 仲裁段波特率 = 90M / 9 / (1 + 7 + 2) = 1M */
/* configure CAN baud rate 1MBps, sample point at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ; // TSG1
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ; // TSG2
can_parameter.prescaler = 9U; // 分频系数
/* initialize CAN */
can_init(CAN0, &can_parameter);
#else // CANFD配置
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = ENABLE;
can_parameter.rec_fifo_overwrite = ENABLE;
can_parameter.trans_fifo_order = ENABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* baudrate 1Mbps, sample piont at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ;
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ;
can_parameter.prescaler = 9U;
/* initialize CAN */
can_init(CAN0, &can_parameter);
can_struct_para_init(CAN_FD_FRAME_STRUCT, &can_fd_parameter);
can_fd_parameter.fd_frame = ENABLE;
can_fd_parameter.excp_event_detect = ENABLE;
can_fd_parameter.delay_compensation = ENABLE;
can_fd_tdc_parameter.tdc_filter = 0x04U;
can_fd_tdc_parameter.tdc_mode = CAN_TDCMOD_CALC_AND_OFFSET;
can_fd_tdc_parameter.tdc_offset = 0x04U;
can_fd_parameter.p_delay_compensation = &can_fd_tdc_parameter;
can_fd_parameter.iso_bosch = CAN_FDMOD_ISO;
can_fd_parameter.esi_mode = CAN_ESIMOD_HARDWARE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 数据段波特率 = 90M / 3 / (1 + 4 + 1) = 5M */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_4TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 3; // 分频系数
/* initialize CAN-FD */
can_fd_init(CAN0, &can_fd_parameter);
#endif
/* initialize filter */
/* configure filter mode */
can_filter.filter_mode = CAN_FILTERMODE_MASK;
can_filter.filter_bits = CAN_FILTERBITS_32BIT;
/* configure filter ID */
can_filter.filter_list_high = 0x0000U;
can_filter.filter_list_low = 0x0000U;
/* configure filter mask */
can_filter.filter_mask_high = 0x0000U;
can_filter.filter_mask_low = 0x0000U;
/* select receiver fifo */
can_filter.filter_fifo_number = CAN_FIFO0;
can_filter.filter_number = 0U;
can_filter.filter_enable = ENABLE;
can_filter_init(CAN0, &can_filter);
/* configure CAN0 NVIC */
nvic_irq_enable(CAN0_RX0_IRQn, 0U, 0U);
/* enable can receive FIFO0 not empty interrupt */
can_interrupt_enable(CAN0, CAN_INTEN_RFNEIE0);
}
void CAN0_RX0_IRQHandler(void)
{
/* check the receive message */
can_message_receive(CAN0, CAN_FIFO0, &can0_rx_message);
#if 1
printf("\r\n can0 receive(id=0x%X) data: ", can0_rx_message.rx_sfid);
for(int i = 0U; i < can0_rx_message.rx_dlen; i++)
{
printf(" %02x", can0_rx_message.rx_data);
}
#endif
}
#endif
#ifdef CAN1_ENABLE
void can1_gpio_config(void)
{
/* enable CAN1 clock */
rcu_periph_clock_enable(RCU_CAN1);
rcu_periph_clock_enable(CAN1RX_CLOCK);
rcu_periph_clock_enable(RCU_AF);
/* configure CAN1 GPIO */
gpio_init(CAN1RX_PORT, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, CAN1RX_PIN);
gpio_init(CAN1TX_PORT, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, CAN1TX_PIN);
gpio_pin_remap_config(GPIO_CAN1_REMAP, ENABLE);
}
void can1_config(void)
{
can_parameter_struct can_parameter;
can_fdframe_struct can_fd_parameter;
can_fd_tdc_struct can_fd_tdc_parameter;
can_filter_parameter_struct can_filter;
can_struct_para_init(CAN_INIT_STRUCT, &can_parameter);
/* initialize CAN register */
can_deinit(CAN1);
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = ENABLE;
can_parameter.rec_fifo_overwrite = ENABLE;
can_parameter.trans_fifo_order = ENABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 仲裁段波特率 = 90M / 9 / (1 + 7 + 2) = 1M */
/* CAN采样率 = (1 + TSG1) / (1 + TSG1 + TSG2) = (1 + 7) / (1 + 7 + 2) = 80% */
/* baudrate 1Mbps, sample piont at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ; // TSG1
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ; // TSG2
can_parameter.prescaler = 9U; // 分频系数
/* initialize CAN */
can_init(CAN1, &can_parameter);
can_struct_para_init(CAN_FD_FRAME_STRUCT, &can_fd_parameter);
can_fd_parameter.fd_frame = ENABLE;
can_fd_parameter.excp_event_detect = ENABLE;
can_fd_parameter.delay_compensation = ENABLE;
can_fd_tdc_parameter.tdc_filter = 0x04U;
can_fd_tdc_parameter.tdc_mode = CAN_TDCMOD_CALC_AND_OFFSET;
can_fd_tdc_parameter.tdc_offset = 0x04U;
can_fd_parameter.p_delay_compensation = &can_fd_tdc_parameter;
can_fd_parameter.iso_bosch = CAN_FDMOD_ISO;
can_fd_parameter.esi_mode = CAN_ESIMOD_HARDWARE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
#if 1
/* 数据段波特率 = 90M / 3 / (1 + 4 + 1) = 5M */
/* CAN采样率 = (1 + TSG1) / (1 + TSG1 + TSG2) = (1 + 4) / (1 + 4 + 1) = 83.3% */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_4TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 3; // 分频系数
#else
/* 数据段波特率 = 90M / 2 / (1 + 6 + 2) = 5M */
/* CAN采样率 = (1 + TSG1) / (1 + TSG1 + TSG2) = (1 + 6) / (1 + 6 + 2) = 77.77% */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_7TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 2; // 分频系数
#endif
/* initialize CAN-FD */
can_fd_init(CAN1, &can_fd_parameter);
/* initialize filter */
/* configure filter mode */
can_filter.filter_mode = CAN_FILTERMODE_MASK;
can_filter.filter_bits = CAN_FILTERBITS_32BIT;
/* configure filter ID */
can_filter.filter_list_high = 0x0000U;
can_filter.filter_list_low = 0x0000U;
/* configure filter mask */
can_filter.filter_mask_high = 0x0000U;
can_filter.filter_mask_low = 0x0000U;
/* select receiver fifo */
can_filter.filter_fifo_number = CAN_FIFO1;
can_filter.filter_number = 15U; // CAN_FCTL默认定义了CAN0和CAN1过滤器序号的分配数量，CAN0使用0-13序号，CAN1使用14-27，可以通过can1_filter_start_bank()修改
can_filter.filter_enable = ENABLE;
can_filter_init(CAN1, &can_filter);
/* configure CAN1 NVIC */
nvic_irq_enable(CAN1_RX1_IRQn, 1U, 1U);
/* enable can receive FIFO0 not empty interrupt */
can_interrupt_enable(CAN1, CAN_INTEN_RFNEIE1);
}
void CAN1_RX1_IRQHandler(void)
{
/* check the receive message */
can_message_receive(CAN1, CAN_FIFO1, &can1_rx_message);
#if 1
printf("\r\n can1 receive(id=0x%X) data: ", can1_rx_message.rx_sfid);
for(int i = 0U; i < can1_rx_message.rx_dlen; i++)
{
printf(" %02x", can1_rx_message.rx_data);
}
#endif
}
#endif
#ifdef CAN2_ENABLE
void can2_gpio_config(void)
{
/* enable CAN2 clock */
rcu_periph_clock_enable(RCU_CAN2);
rcu_periph_clock_enable(CAN2RX_CLOCK);
rcu_periph_clock_enable(RCU_AF);
/* configure CAN2 GPIO */
gpio_init(CAN2RX_PORT, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, CAN2RX_PIN);
gpio_init(CAN2TX_PORT, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, CAN2TX_PIN);
gpio_afio_port_config(AFIO_PB10_CAN2_CFG, ENABLE);
gpio_afio_port_config(AFIO_PB11_CAN2_CFG, ENABLE);
}
void can2_config(void)
{
can_parameter_struct can_parameter;
can_fdframe_struct can_fd_parameter;
can_fd_tdc_struct can_fd_tdc_parameter;
can_filter_parameter_struct can_filter;
can_struct_para_init(CAN_INIT_STRUCT, &can_parameter);
/* initialize CAN register */
can_deinit(CAN2);
/* initialize CAN parameters */
can_parameter.time_triggered = DISABLE;
can_parameter.auto_bus_off_recovery = DISABLE;
can_parameter.auto_wake_up = DISABLE;
can_parameter.auto_retrans = ENABLE;
can_parameter.rec_fifo_overwrite = ENABLE;
can_parameter.trans_fifo_order = ENABLE;
can_parameter.working_mode = CAN_NORMAL_MODE;
/* baudrate 1Mbps, sample piont at 80% */
can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
can_parameter.time_segment_1 = CAN_BT_BS1_7TQ;
can_parameter.time_segment_2 = CAN_BT_BS2_2TQ;
can_parameter.prescaler = 9U;
/* initialize CAN */
can_init(CAN2, &can_parameter);
can_struct_para_init(CAN_FD_FRAME_STRUCT, &can_fd_parameter);
can_fd_parameter.fd_frame = ENABLE;
can_fd_parameter.excp_event_detect = ENABLE;
can_fd_parameter.delay_compensation = ENABLE;
can_fd_tdc_parameter.tdc_filter = 0x04U;
can_fd_tdc_parameter.tdc_mode = CAN_TDCMOD_CALC_AND_OFFSET;
can_fd_tdc_parameter.tdc_offset = 0x04U;
can_fd_parameter.p_delay_compensation = &can_fd_tdc_parameter;
can_fd_parameter.iso_bosch = CAN_FDMOD_ISO;
can_fd_parameter.esi_mode = CAN_ESIMOD_HARDWARE;
/* CAN波特率 = 时钟频率 / 分频系数 / (1 + TSG1 + TSG2) */
/* 数据段波特率 = 90M / 3 / (1 + 4 + 1) = 5M */
can_fd_parameter.data_resync_jump_width = CAN_BT_SJW_1TQ;
can_fd_parameter.data_time_segment_1 = CAN_BT_BS1_4TQ; // TSG1
can_fd_parameter.data_time_segment_2 = CAN_BT_BS2_1TQ; // TSG2
/* CAN-FD data segement prescaler should be the same as non-data segement prescaler */
can_fd_parameter.data_prescaler = 3; // 分频系数
/* initialize CAN-FD */
can_fd_init(CAN2, &can_fd_parameter);
/* initialize filter */
/* configure filter mode */
can_filter.filter_mode = CAN_FILTERMODE_MASK;
can_filter.filter_bits = CAN_FILTERBITS_32BIT;
/* configure filter ID */
can_filter.filter_list_high = 0x0000U;
can_filter.filter_list_low = 0x0000U;
/* configure filter mask */
can_filter.filter_mask_high = 0x0000U;
can_filter.filter_mask_low = 0x0000U;
/* select receiver fifo */
can_filter.filter_fifo_number = CAN_FIFO0;
can_filter.filter_number = 1U;
can_filter.filter_enable = ENABLE;
can_filter_init(CAN2, &can_filter);
/* configure CAN2 NVIC */
nvic_irq_enable(CAN2_RX0_IRQn, 0U, 0U);
/* enable can receive FIFO0 not empty interrupt */
can_interrupt_enable(CAN2, CAN_INTEN_RFNEIE0);
}
void CAN2_RX0_IRQHandler(void)
{
/* check the receive message */
can_message_receive(CAN2, CAN_FIFO0, &can2_rx_message);
#if 1
printf("\r\n can2 receive(id=0x%X) data: ", can2_rx_message.rx_sfid);
for(int i = 0U; i < can2_rx_message.rx_dlen; i++)
{
printf(" %02x", can2_rx_message.rx_data);
}
#endif
}
#endif
#if defined (CAN0_ENABLE) || defined (CAN1_ENABLE) || defined (CAN2_ENABLE)
int can_send_message(uint8_t ch, can_trasnmit_data_t can_data)
{
uint8_t i;
can_trasnmit_message_struct *can_tx_message;
switch (ch)
{
case 0:
#ifdef CAN0_ENABLE
can_tx_message = &can0_tx_message;
#endif
break;
case 1:
#ifdef CAN1_ENABLE
can_tx_message = &can1_tx_message;
#endif
break;
case 2:
#ifdef CAN2_ENABLE
can_tx_message = &can2_tx_message;
#endif
break;
default:
break;
}
if(can_data.frame_format == 0)
{// 标准帧
can_tx_message->tx_sfid = can_data.id;
}
else
{// 扩展帧
can_tx_message->tx_efid = can_data.id;
}
if(can_data.can_type == 0)
{// CAN
can_tx_message->fd_flag = 0;
can_tx_message->fd_brs = 0;
}
else if(can_data.can_type == 1)
{// CANFD
can_tx_message->fd_flag = 1;
}
else if(can_data.can_type == 2)
{// CANFD加速
can_tx_message->fd_flag = 1;
can_tx_message->fd_brs = 1;
}
can_tx_message->fd_esi = 0;
memcpy(can_tx_message->tx_data, can_data.buf, can_data.buf_len);
// CANFD模式下，数据长度只能为0 - 8, 12, 16, 20, 24, 32, 48, 64
if(can_data.buf_len > 48)
{
can_tx_message->tx_dlen = 64;
}
else if(can_data.buf_len > 32)
{
can_tx_message->tx_dlen = 48;
}
else if(can_data.buf_len > 24)
{
can_tx_message->tx_dlen = 32;
}
else if(can_data.buf_len > 20)
{
can_tx_message->tx_dlen = 24;
}
else if(can_data.buf_len > 16)
{
can_tx_message->tx_dlen = 20;
}
else if(can_data.buf_len > 12)
{
can_tx_message->tx_dlen = 16;
}
else if(can_data.buf_len > 8)
{
can_tx_message->tx_dlen = 12;
}
else
{
can_tx_message->tx_dlen = can_data.buf_len;
}
#if 1
printf("\r\n can(%d) transmit data(id: 0x%x): ", ch, can_tx_message->tx_sfid);
for(i = 0U; i < can_tx_message->tx_dlen; i++)
{
printf(" %02x", can_tx_message->tx_data);
}
#endif
/* transmit message */
if(can_message_transmit(CAN2, can_tx_message) != CAN_NOMAILBOX)
{// 发送成功
return 1;
}
return 0;
}
#endif
void can_tx_test(void)
{
uint8_t i;
can_trasnmit_data_t can_data;
for (i = 0; i < 64; i++)
{
can_data.buf = i;
}
#ifdef CAN0_ENABLE
can_data.id = 0x123;
can_data.frame_format = 0; // 标准帧
can_data.can_type = 0; // CAN
can_data.buf_len = 8; // 数据长度
can_send_message(0, can_data);
#endif
#ifdef CAN1_ENABLE
can_data.id = 0x456;
can_data.frame_format = 0; // 标准帧
can_data.can_type = 1; // CANFD
can_data.buf_len = 16; // 数据长度
can_send_message(1, can_data);
#endif
#ifdef CAN2_ENABLE
can_data.id = 0x789;
can_data.frame_format = 0; // 标准帧
can_data.can_type = 2; // CANFD加速
can_data.buf_len = 64; // 数据长度
can_send_message(2, can_data);
#endif
}
void can_user_init(void)
{
#ifdef CAN0_ENABLE
// CAN0 init
can0_gpio_config();
can0_config();
/* initialize can0 transmit message */
can_struct_para_init(CAN_TX_MESSAGE_STRUCT, &can0_tx_message);
/* initialize can0 receive message */
can_struct_para_init(CAN_RX_MESSAGE_STRUCT, &can0_rx_message);
#endif
#ifdef CAN1_ENABLE
// CAN1 init
can1_gpio_config();
can1_config();
/* initialize can1 transmit message */
can_struct_para_init(CAN_TX_MESSAGE_STRUCT, &can1_tx_message);
/* initialize can1 receive message */
can_struct_para_init(CAN_RX_MESSAGE_STRUCT, &can1_rx_message);
#endif
#ifdef CAN2_ENABLE
// CAN2 init
can2_gpio_config();
can2_config();
/* initialize can2 transmit message */
can_struct_para_init(CAN_TX_MESSAGE_STRUCT, &can2_tx_message);
/* initialize can2 receive message */
can_struct_para_init(CAN_RX_MESSAGE_STRUCT, &can2_rx_message);
#endif
printf("can init success\r\n");
}
can.h：
#ifndef __CAN_HANDLE_H
#define __CAN_HANDLE_H
#include "gd32e50x_can.h"
#define CAN0_ENABLE
#define CAN1_ENABLE
#define CAN2_ENABLE
#define CAN0RX_CLOCK RCU_GPIOB
#define CAN0RX_PORT GPIOB
#define CAN0RX_PIN GPIO_PIN_8
#define CAN0TX_CLOCK RCU_GPIOB
#define CAN0TX_PORT GPIOB
#define CAN0TX_PIN GPIO_PIN_9
#define CAN1RX_CLOCK RCU_GPIOB
#define CAN1RX_PORT GPIOB
#define CAN1RX_PIN GPIO_PIN_5
#define CAN1TX_CLOCK RCU_GPIOB
#define CAN1TX_PORT GPIOB
#define CAN1TX_PIN GPIO_PIN_6
#define CAN2RX_CLOCK RCU_GPIOB
#define CAN2RX_PORT GPIOB
#define CAN2RX_PIN GPIO_PIN_10
#define CAN2TX_CLOCK RCU_GPIOB
#define CAN2TX_PORT GPIOB
#define CAN2TX_PIN GPIO_PIN_11
typedef struct
{
uint32_t id; // CAN ID
uint8_t frame_format; // format of frame | 0：standard | 1：extended format
uint8_t can_type; // CAN type | 0：CAN | 1：CANFD | 2：CANFD加速
uint8_t buf[64]; // CAN buf
uint8_t buf_len; // CAN buf len
} can_trasnmit_data_t;
void can_user_init(void);
void can_tx_test(void);
#endif
main.c：
#include "main.h"
#include "uart.h"
#include "can.h"
int main(void)
{
// systick_config();
uart_user_init();
can_user_init();
printf("app init success.\n");
can_tx_test();
while(1)
{
}
}
3 测试验证
把MCU三路CAN接到一起，并接入CAN盒的同一通道。
用CAN盒抓取数据如下图所示，MCU启动后一次通过3路CAN发送不同的数据。
MCU单路CAN接CAN盒，然后用CAN盒发送数据，MCU接收如下图所示：
MCU收到数据并通过串口打印接收log。
————————————————
版权声明：本文为博主原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。
原文链接：https://blog.csdn.net/ShenZhen_zixian/article/details/142966125
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