GD32双路CAN踩坑记录
目录
- GD32双路CAN踩坑记录
- 1 问题描述
- 2 原因分析
- 3 解决办法
- 4 CAN配置参考代码
1 问题描述
GD32的CAN1无法进入接收中断，收不到数据。
注：MCU使用的是GD32E50x，其他型号不确定是否一样，本文只以GD32E50x举例说明。
2 原因分析
GD32的CAN过滤器总共有28个，通过过滤器控制寄存器（CAN_FCTL）打开或关闭，具体如下：
其中问题就出现在上图的HBC1F上面，CAN0使用的是过滤器编号0到编号(HBC1F-1)，CAN1使用的是过滤器编号(HBC1F)到27，而这个默认值是0xE(14)，也就是说CAN0默认使用的是编号为0-13的过滤器，CAN1默认使用的是编号为0-27的过滤器，因此，在初始化CAN1的时候，过滤器编号要在这个范围内才能被正确使用，否则是接收不到CAN数据的。
3 解决办法
1、使用编号为15-28的过滤器
2、通过修改CAN_FCTL寄存器的HBC1F，调整过滤器编号的分配
其中GD32固件库有封装函数可以修改HBC1F，函数原形如下：
/*!\brief set CAN1 fliter start bank number\param[in] start_bank: CAN1 start bank numberonly one parameter can be selected which is shown as below:\arg (1..27)\param[out] none\retval none
*/
void can1_filter_start_bank(uint8_t start_bank)
{/* filter lock disable */CAN_FCTL(CAN0) |= CAN_FCTL_FLD;/* set CAN1 filter start number */CAN_FCTL(CAN0) &= ~(uint32_t)CAN_FCTL_HBC1F;CAN_FCTL(CAN0) |= FCTL_HBC1F(start_bank);/* filter lock enable */CAN_FCTL(CAN0) &= ~CAN_FCTL_FLD;
}
4 CAN配置参考代码
#include "main.h"
#include "stdio.h"can_trasnmit_message_struct can0_tx_message;
can_trasnmit_message_struct can1_tx_message;
can_receive_message_struct can0_rx_message;
can_receive_message_struct can1_rx_message;void can0_gpio_config(void)
{/* enable CAN0 clock */rcu_periph_clock_enable(RCU_CAN0);rcu_periph_clock_enable(RCU_GPIOB);rcu_periph_clock_enable(RCU_AF);/* configure CAN0 GPIO */gpio_init(GPIOB, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, GPIO_PIN_8);gpio_init(GPIOB, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_9);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 1 // 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; // TSG1can_parameter.time_segment_2 = CAN_BT_BS2_2TQ; // TSG2can_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; // TSG1can_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);
}int can0_send_message(void)
{uint8_t i;uint16_t id = 1;can0_tx_message.tx_sfid = id;can0_tx_message.fd_flag = 0;can0_tx_message.fd_brs = 0;can0_tx_message.fd_esi = 0;can0_tx_message.tx_dlen = 8;for(i = 0; i < 8; i++) {can0_tx_message.tx_data[i] = i;}
#if 0printf("\r\n can0 transmit data(id: 0x%x): ", can0_tx_message.tx_sfid);for(i = 0U; i < can0_tx_message.tx_dlen; i++) {printf(" %02x", can0_tx_message.tx_data[i]);}
#endif/* transmit message */if(can_message_transmit(CAN0, &can0_tx_message) != CAN_NOMAILBOX){return 1;}return 0;
}void CAN0_RX0_IRQHandler(void)
{/* check the receive message */can_message_receive(CAN0, CAN_FIFO0, &can0_rx_message);LOG("\r\n can0 receive(id=0x%X) data: ", can0_rx_message.rx_sfid);for(int i = 0U; i < can0_rx_message.rx_dlen; i++) {LOG(" %02x", can0_rx_message.rx_data[i]);}
}void can1_gpio_config(void)
{/* enable CAN1 clock */rcu_periph_clock_enable(RCU_CAN1);rcu_periph_clock_enable(RCU_GPIOB);rcu_periph_clock_enable(RCU_AF);/* configure CAN1 GPIO */gpio_init(GPIOB, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, GPIO_PIN_5);gpio_init(GPIOB, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_6);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; // TODO 自动重传是否需要使能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 *//* baudrate 1Mbps, sample piont at 80% */can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;can_parameter.time_segment_1 = CAN_BT_BS1_7TQ; // TSG1can_parameter.time_segment_2 = CAN_BT_BS2_2TQ; // TSG2can_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) *//* 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; // TSG1can_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(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);
}int can1_send_message(void)
{uint8_t i;uint16_t id = 2;can1_tx_message.tx_sfid = id;can1_tx_message.fd_flag = 1;can1_tx_message.fd_brs = 1;can1_tx_message.fd_esi = 0;can1_tx_message.tx_dlen = 8;for(i = 0; i < 8; i++) {can1_tx_message.tx_data[i] = i;}
#if 0printf("\r\n can1 transmit data(id: 0x%x): ", can1_tx_message.tx_sfid);for(i = 0U; i < can1_tx_message.tx_dlen; i++) {printf(" %02x", can1_tx_message.tx_data[i]);}
#endif/* transmit message */if(can_message_transmit(CAN1, &can1_tx_message) != CAN_NOMAILBOX){return 1;}return 0;
}void CAN1_RX1_IRQHandler(void)
{/* check the receive message */can_message_receive(CAN1, CAN_FIFO1, &can1_rx_message);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[i]);}
}void can_user_init(void)
{// CAN0 initcan0_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);// CAN1 initcan1_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);printf("can init success\r\n");
}