GD32VF103_CAN发送

前言

GD32VF103_环境配置_GPIO_外部中断
GD32VF103_定时器中断
GD32VF103_串口发送_printf_接收中断_DMA
GD32VF103_DAC
我们前三节写了GPIO, EXTI, TIMER, USART, DAC的用例, 本节写 CAN 发送的用例, 为什么是发送不是接收, 还不是因为接收比较复杂, 没有调好… 用的 CAN1(PB13--CAN1_TX, PB12--CAN1_RX), 自己拿烙铁焊了 CAN电平转换芯片 TCAN1051DQ1, 带Q的车规的片子:


CAN1接CAN分析仪, 500k, 终端电阻用了CAN分析仪上的120Ω, 虽然不是60Ω, 在这里问题不大.

新建工程

打开NucleiStudio:

• File -> New -> C/C++ Project, 选择C Managed Build
• 选择GigaDevice RISC-V Project, 填入工程名
• MCU默认暂时只有GD32VF103, 然后Demo也没法选, 只有Running_LED, 不变
• 下一步, 完成.

CAN发送

CAN, 标准帧, 扩展帧等的基本原理和相关资料不再赘述, 网上搜去, STM32的资料或者搞汽车方面的比较多.

主要配置下CAN的通讯速率, 应该是APB1的54M时钟, 预分配(prescaler)12, 得4.5MHz, 然后 can_parameter.time_segment_1 = CAN_BT_BS1_5TQ;, can_parameter.time_segment_2 = CAN_BT_BS2_3TQ;, 所以最后通讯速率 4.5M/(5+3+1) = 0.5M = 500k, 与can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;关系不大.

代码如下:

#include "gd32vf103.h"
#include "systick.h"

can_trasnmit_message_struct transmit_message;

void can1_config(void) {
    can_parameter_struct can_parameter;
    can_filter_parameter_struct can_filter;
    /* initialize CAN register */
    can_deinit(CAN1);

    /* initialize CAN */
    can_parameter.time_triggered = DISABLE;
    can_parameter.auto_bus_off_recovery = ENABLE;
    can_parameter.auto_wake_up = ENABLE;
    can_parameter.auto_retrans = ENABLE;	//no_auto_retrans
    can_parameter.rec_fifo_overwrite = DISABLE;
    can_parameter.trans_fifo_order = DISABLE;
    can_parameter.working_mode = CAN_NORMAL_MODE;
    can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
    can_parameter.time_segment_1 = CAN_BT_BS1_5TQ;
    can_parameter.time_segment_2 = CAN_BT_BS2_3TQ;
    /* baudrate 1Mbps */
    can_parameter.prescaler = 12;	//54M / 12 / (5+3+1) =  500kbps
    can_init(CAN1, &can_parameter);
}

int main(void) {
    rcu_periph_clock_enable(RCU_CAN1);
    rcu_periph_clock_enable(RCU_GPIOB);
    gpio_init(GPIOB, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_13); //PB13 -- CAN1_TX
    gpio_init(GPIOB, GPIO_MODE_IPU, GPIO_OSPEED_50MHZ, GPIO_PIN_12);	//PB12 -- CAN1_RX
    //gpio_pin_remap_config(GPIO_CAN1_REMAP,DISABLE);	//Remap

    can1_config();

    transmit_message.tx_sfid = 0x321;	//standard format frame identifier
    transmit_message.tx_efid = 0x00;	//extended format frame identifier
    transmit_message.tx_ft = CAN_FT_DATA;	//type of frame, data or remote
    transmit_message.tx_ff = CAN_FF_STANDARD;	//format of frame, standard or extended format
    transmit_message.tx_dlen = 2;	//data length
    transmit_message.tx_data[0] = 0x00;
    transmit_message.tx_data[1] = 0x00;

	while(1) {
		++transmit_message.tx_data[1];
		can_message_transmit(CAN1, &transmit_message);
		delay_1ms(1000);
	}

	return 0;
}

调试运行

结果如下:

符合代码预期.

工程代码

https://download.csdn.net/download/weifengdq/11951375