【转】STM32系列第25篇--CAN总线2
本帖最后由 yujietian 于 2017-5-18 23:31 编辑//can.c
#include "can.h"
#include "led.h"
#include "delay.h"
#include "usart.h"
//CAN初始化
//tsjw:重新同步跳跃时间单元.范围:CAN_SJW_1tq~ CAN_SJW_4tq
//tbs2:时间段2的时间单元. 范围:CAN_BS2_1tq~CAN_BS2_8tq;
//tbs1:时间段1的时间单元. 范围:CAN_BS1_1tq ~CAN_BS1_16tq
//brp :波特率分频器.范围:1~1024;tq=(brp)*tpclk1
//波特率=Fpclk1/((tbs1+1+tbs2+1+1)*brp);
//mode:CAN_Mode_Normal,普通模式;CAN_Mode_LoopBack,回环模式;
//Fpclk1的时钟在初始化的时候设置为36M,如果设置CAN_Mode_Init(CAN_SJW_1tq,CAN_BS2_8tq,CAN_BS1_9tq,4,CAN_Mode_LoopBack);
//则波特率为:36M/((8+9+1)*4)=500Kbps
//返回值:0,初始化OK;
// 其他,初始化失败;
u8 CAN_Mode_Init(u8 tsjw,u8 tbs2,u8 tbs1,u16 brp,u8 mode)
{
GPIO_InitTypeDef GPIO_InitStructure;
CAN_InitTypeDef CAN_InitStructure;
CAN_FilterInitTypeDef CAN_FilterInitStructure;
#if CAN_RX0_INT_ENABLE
NVIC_InitTypeDef NVIC_InitStructure;
#endif
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能PORTA时钟
RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE); //使能CAN1时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽
GPIO_Init(GPIOA, &GPIO_InitStructure); //初始化IO
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; //上拉输入
GPIO_Init(GPIOA, &GPIO_InitStructure); //初始化IO
//CAN单元设置
CAN_InitStructure.CAN_TTCM=DISABLE; //非时间触发通信模式
CAN_InitStructure.CAN_ABOM=DISABLE; //软件自动离线管理
CAN_InitStructure.CAN_AWUM=DISABLE; //睡眠模式通过软件唤醒(清除CAN->MCR的SLEEP位)
CAN_InitStructure.CAN_NART=ENABLE; //禁止报文自动传送
CAN_InitStructure.CAN_RFLM=DISABLE; //报文不锁定,新的覆盖旧的
CAN_InitStructure.CAN_TXFP=DISABLE; //优先级由报文标识符决定
CAN_InitStructure.CAN_Mode= mode; //模式设置： mode:0,普通模式;1,回环模式;
//设置波特率
CAN_InitStructure.CAN_SJW=tsjw; //重新同步跳跃宽度(Tsjw)为tsjw+1个时间单位CAN_SJW_1tq CAN_SJW_2tq CAN_SJW_3tq CAN_SJW_4tq
CAN_InitStructure.CAN_BS1=tbs1; //Tbs1=tbs1+1个时间单位CAN_BS1_1tq ~CAN_BS1_16tq
CAN_InitStructure.CAN_BS2=tbs2; //Tbs2=tbs2+1个时间单位CAN_BS2_1tq ~ CAN_BS2_8tq
CAN_InitStructure.CAN_Prescaler=brp; //分频系数(Fdiv)为brp+1
CAN_Init(CAN1, &CAN_InitStructure); //初始化CAN1
CAN_FilterInitStructure.CAN_FilterNumber=0; //过滤器0
CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask; //屏蔽位模式
CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;//32位宽
CAN_FilterInitStructure.CAN_FilterIdHigh=0x0000; //32位ID
CAN_FilterInitStructure.CAN_FilterIdLow=0x0000;
CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0x0000;//32位MASK
CAN_FilterInitStructure.CAN_FilterMaskIdLow=0x0000;
CAN_FilterInitStructure.CAN_FilterFIFOAssignment=CAN_Filter_FIFO0;//过滤器0关联到FIFO0
CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;//激活过滤器0
CAN_FilterInit(&CAN_FilterInitStructure); //滤波器初始化
#if CAN_RX0_INT_ENABLE
CAN_ITConfig(CAN1,CAN_IT_FMP0,ENABLE); //FIFO0消息挂号中断允许.
NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1; // 主优先级为1
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; // 次优先级为0
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
#endif
return 0;
}
#if CAN_RX0_INT_ENABLE//使能RX0中断
//中断服务函数
void USB_LP_CAN1_RX0_IRQHandler(void)
{
CanRxMsg RxMessage;
int i=0;
CAN_Receive(CAN1, 0, &RxMessage);
for(i=0;i<8;i++)
printf("rxbuf[%d]:%d\r\n",i,RxMessage.Data);
}
#endif
//can发送一组数据(固定格式:ID为0X12,标准帧,数据帧)
//len:数据长度(最大为8)
//msg:数据指针,最大为8个字节.
//返回值:0,成功;
// 其他,失败;
u8 Can_Send_Msg(u8* msg,u8 len)
{
u8 mbox;
u16 i=0;
CanTxMsg TxMessage;
TxMessage.StdId=0x12; // 标准标识符
TxMessage.ExtId=0x12; // 设置扩展标示符
TxMessage.IDE=CAN_Id_Standard;// 标准帧
TxMessage.RTR=CAN_RTR_Data; // 数据帧
TxMessage.DLC=len; // 要发送的数据长度
for(i=0;i<len;i++)
TxMessage.Data=msg;
mbox= CAN_Transmit(CAN1, &TxMessage);
i=0;
while((CAN_TransmitStatus(CAN1, mbox)==CAN_TxStatus_Failed)&&(i<0XFFF))i++; //等待发送结束
if(i>=0XFFF)return 1;
return 0;
}
//can口接收数据查询
//buf:数据缓存区;
//返回值:0,无数据被收到;
// 其他,接收的数据长度;
u8 Can_Receive_Msg(u8 *buf)
{
u32 i;
CanRxMsg RxMessage;
if( CAN_MessagePending(CAN1,CAN_FIFO0)==0)return 0; //没有接收到数据,直接退出
CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);//读取数据
for(i=0;i<8;i++)
buf=RxMessage.Data;
return RxMessage.DLC;
}
main.c
#include "led.h"
#include "delay.h"
#include "key.h"
#include "sys.h"
#include "lcd.h"
#include "usart.h"
#include "can.h"
int main(void)
{
u8 key;
u8 i=0,t=0;
u8 cnt=0;
u8 canbuf;
u8 res;
u8 mode=CAN_Mode_LoopBack;//CAN工作模式;CAN_Mode_Normal(0)：普通模式，CAN_Mode_LoopBack(1)：环回模式
delay_init(); //延时函数初始化
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//设置中断优先级分组为组2：2位抢占优先级，2位响应优先级
uart_init(115200); //串口初始化为115200
LED_Init(); //初始化与LED连接的硬件接口
LCD_Init(); //初始化LCD
KEY_Init(); //按键初始化
CAN_Mode_Init(CAN_SJW_1tq,CAN_BS2_8tq,CAN_BS1_9tq,4,CAN_Mode_LoopBack);//CAN初始化环回模式,波特率500Kbps
POINT_COLOR=RED;//设置字体为红色
LCD_ShowString(60,50,200,16,16,"WarShip STM32");
LCD_ShowString(60,70,200,16,16,"CAN TEST");
LCD_ShowString(60,90,200,16,16,"ATOM@ALIENTEK");
LCD_ShowString(60,110,200,16,16,"2015/1/15");
LCD_ShowString(60,130,200,16,16,"LoopBack Mode");
LCD_ShowString(60,150,200,16,16,"KEY0:Send WK_UP:Mode");//显示提示信息
POINT_COLOR=BLUE;//设置字体为蓝色
LCD_ShowString(60,170,200,16,16,"Count:"); //显示当前计数值
LCD_ShowString(60,190,200,16,16,"Send Data:"); //提示发送的数据
LCD_ShowString(60,250,200,16,16,"Receive Data:"); //提示接收到的数据
while(1)
{
key=KEY_Scan(0);
if(key==KEY0_PRES)//KEY0按下,发送一次数据
{
for(i=0;i<8;i++)
{
canbuf=cnt+i;//填充发送缓冲区
if(i<4)LCD_ShowxNum(60+i*32,210,canbuf,3,16,0X80); //显示数据
else LCD_ShowxNum(60+(i-4)*32,230,canbuf,3,16,0X80); //显示数据
}
res=Can_Send_Msg(canbuf,8);//发送8个字节
if(res)LCD_ShowString(60+80,190,200,16,16,"Failed"); //提示发送失败
else LCD_ShowString(60+80,190,200,16,16,"OK "); //提示发送成功
}else if(key==WKUP_PRES)//WK_UP按下，改变CAN的工作模式
{
mode=!mode;
CAN_Mode_Init(CAN_SJW_1tq,CAN_BS2_8tq,CAN_BS1_9tq,4,mode);//CAN普通模式初始化, 波特率500Kbps
POINT_COLOR=RED;//设置字体为红色
if(mode==0)//普通模式，需要2个开发板
{
LCD_ShowString(60,130,200,16,16,"Nnormal Mode ");
}else //回环模式,一个开发板就可以测试了.
{
LCD_ShowString(60,130,200,16,16,"LoopBack Mode");
}
POINT_COLOR=BLUE;//设置字体为蓝色
}
key=Can_Receive_Msg(canbuf);
if(key)//接收到有数据
{
LCD_Fill(60,270,130,310,WHITE);//清除之前的显示
for(i=0;i<key;i++)
{
if(i<4)LCD_ShowxNum(60+i*32,270,canbuf,3,16,0X80); //显示数据
else LCD_ShowxNum(60+(i-4)*32,290,canbuf,3,16,0X80); //显示数据
}
}
t++;
delay_ms(10);
if(t==20)
{
LED0=!LED0;//提示系统正在运行
t=0;
cnt++;
LCD_ShowxNum(60+48,170,cnt,3,16,0X80);//显示数据
}
}
}
前来顶帖
页:
[1]