stm32f407 can发送代码
时间: 2023-08-14 14:04:12 浏览: 95
以下是使用HAL库在STM32F407芯片上发送CAN消息的示例代码:
```
#include "stm32f4xx_hal.h"
#include "main.h"
CAN_HandleTypeDef hcan1;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_CAN1_Init(void);
int main(void)
{
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_CAN1_Init();
// 构造CAN消息
CAN_TxHeaderTypeDef TxHeader;
uint8_t TxData[8];
TxHeader.StdId = 0x123; // 标准标识符
TxHeader.RTR = CAN_RTR_DATA; // 数据帧
TxHeader.IDE = CAN_ID_STD; // 标准帧
TxHeader.DLC = 8; // 数据长度为8字节
TxData[0] = 0x11;
TxData[1] = 0x22;
TxData[2] = 0x33;
TxData[3] = 0x44;
TxData[4] = 0x55;
TxData[5] = 0x66;
TxData[6] = 0x77;
TxData[7] = 0x88;
// 发送CAN消息
uint32_t TxMailbox;
if (HAL_CAN_AddTxMessage(&hcan1, &TxHeader, TxData, &TxMailbox) != HAL_OK) {
Error_Handler();
}
while (1) {
}
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLM = 8;
RCC_OscInitStruct.PLL.PLLN = 50;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = 2;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
Error_Handler();
}
/** Configure the SYSCLKSource, HCLK, PCLK1 and PCLK2 clocks dividers
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK) {
Error_Handler();
}
}
static void MX_CAN1_Init(void)
{
hcan1.Instance = CAN1;
hcan1.Init.Prescaler = 5;
hcan1.Init.Mode = CAN_MODE_NORMAL;
hcan1.Init.SyncJumpWidth = CAN_SJW_1TQ;
hcan1.Init.TimeSeg1 = CAN_BS1_11TQ;
hcan1.Init.TimeSeg2 = CAN_BS2_2TQ;
hcan1.Init.TimeTriggeredMode = DISABLE;
hcan1.Init.AutoBusOff = ENABLE;
hcan1.Init.AutoWakeUp = DISABLE;
hcan1.Init.AutoRetransmission = ENABLE;
hcan1.Init.ReceiveFifoLocked = DISABLE;
hcan1.Init.TransmitFifoPriority = DISABLE;
if (HAL_CAN_Init(&hcan1) != HAL_OK) {
Error_Handler();
}
}
void Error_Handler(void)
{
while (1) {
}
}
```
在此示例中,我们使用标准标识符0x123构造了一个8字节的CAN数据帧,并将其发送到CAN总线上。在MX_CAN1_Init函数中,我们使用了以下CAN初始化配置:
- 波特率为1Mbps(时钟频率为50MHz,分频系数为5)
- 正常模式
- 时间段1为11个时间单位,时间段2为2个时间单位
- 自动总线关闭(当总线错误次数超过一定阈值时,自动关闭总线)
- 自动重传(如果发送失败,自动重传)
- 禁止接收FIFO锁定
- 禁止传输FIFO优先级
当我们调用HAL_CAN_AddTxMessage函数发送CAN消息时,它会将CAN消息添加到CAN发送FIFO中,并返回用于该消息的邮箱号(TxMailbox)。您可以使用HAL_CAN_GetTxMailboxesFreeLevel函数检查发送FIFO中可用的邮箱数量。如果返回值为0,则发送FIFO已满,您需要等待一段时间,或者实现重传机制来处理此问题。
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