拿到开发板有一段时间，看了下资料，使用mbed平台那简直是太简单了,但mbed封装的太严实，实在是不利于我们了解MCU内部运作机理，所以还是要使用ST的库（直接寄存器操作就免了，我不想回到石器时代），现在ST库除了F1系列已经改变，采用新的HAL Drivers的方式，这种方式更友好，更符合软件工程。使用STM32CubeMX把和MCU相关的代码已经生成的90%了，剩下和10%需要自己来完成，所有的中断基本上采用“伪回调”的方式，使用用户更专注于业务算法本身。废话不多说了，直接上代码：

-------------------------------------------------------------------------------传说中的分界线----------------------------------------------------------------------------

main.c

#include "stm32l0xx_hal.h"

#include "dma.h"

#include "i2c.h"

#include "tim.h"

#include "usart.h"

#include "gpio.h"

#include "mpu6050.h"

#include "visualscope.h"

#include <string.h>

#include <math.h>

/* Private variables ---------------------------------------------------------*/

#define RXSIZE 8

#define TXSIZE 8

uint8_t rxBuffer[RXSIZE];

uint8_t txBuffer[TXSIZE];

float Angle_accel = 0;

float Angle_gyro = 0;

float Angle_comp = 0;

uint8_t outAngleData[10];

/* USER CODE BEGIN 0 */

/*---------------------------------------------------------------------------------------------------------*/

/*重力加速度算出的角度 */

/*---------------------------------------------------------------------------------------------------------*/

int32_t Calc_AngleAccel()

{

int32_t value = 0;

value = GetAccelValue('x');

if(value > 16384)

Angle_accel = -(asin(1) * 180 / 3.1415296);

else

Angle_accel = -(asin(value * 1.0 / 16384) * 180 / 3.1415296);

return value;

}

/*---------------------------------------------------------------------------------------------------------*/

/* 角速度算出来的角度（积分） */

/*---------------------------------------------------------------------------------------------------------*/

int32_t Calc_AngleGyro()

{

int32_t value = 0;

value = GetGyroValue('y');

Angle_gyro += (value / 16.384 * 0.01);

return value;

}

/*---------------------------------------------------------------------------------------------------------*/

/* 互补滤波求角度 */

/*---------------------------------------------------------------------------------------------------------*/

float ComplementFilter(int32_t simpleGyro)

{

Angle_comp = 0.98 * (Angle_comp + -simpleGyro / 16.384 * 0.01) + 0.02 * Angle_accel;

return Angle_comp;

}

/*---------------------------------------------------------------------------------------------------------*/

/* 输出角度至上位机 */

/*---------------------------------------------------------------------------------------------------------*/

void VisualScopeAngleOutput()

{

int AngleValue_Accel,AngleValue_Gyro,AngleValue_Comp;

uint16_t crcValue;

AngleValue_Accel = ceil(Angle_accel * 10 -0.5);

AngleValue_Gyro = ceil(Angle_gyro * 10 - 0.5);

AngleValue_Comp = ceil(Angle_comp * 10 - 0.5);

outAngleData[0] = AngleValue_Accel & 0xFF;

outAngleData[1] = AngleValue_Accel >> 8;

outAngleData[2] = AngleValue_Gyro & 0xFF;

outAngleData[3] = AngleValue_Gyro >> 8;

outAngleData[4] = AngleValue_Comp & 0xFF;

outAngleData[5] = AngleValue_Comp >> 8;

//计算CRC

crcValue =CRC_CHECK(outAngleData,8);

outAngleData[8] = crcValue & 0xFF;

outAngleData[9] = crcValue >> 8;

//发送至上位机

HAL_UART_Transmit_DMA(&huart2,outAngleData,sizeof(outAngleData));

}

/* USER CODE END 0 */

/* Private function prototypes -----------------------------------------------*/

void SystemClock_Config(void);

int main(void)

{

/* USER CODE BEGIN 1 */

/* USER CODE END 1 */

/* MCU Configuration----------------------------------------------------------*/

/* Reset of all peripherals, Initializes the Flash interface and the Systick. */

HAL_Init();

/* Configure the system clock */

SystemClock_Config();

/* System interrupt init*/

HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);

/* Initialize all configured peripherals */

MX_GPIO_Init();

MX_DMA_Init();

MX_I2C1_Init();

MX_TIM2_Init();

MX_USART2_UART_Init();

InitMPU6050();

/* USER CODE BEGIN 2 */

HAL_UART_Receive_DMA(&huart2,rxBuffer,RXSIZE);

HAL_TIM_Base_Start_IT(&htim2);

/* USER CODE END 2 */

/* USER CODE BEGIN 3 */

/* Infinite loop */

while (1)

{

HAL_GPIO_TogglePin(GPIOA,GPIO_PIN_5);

VisualScopeAngleOutput();

HAL_Delay(100);

}

/* USER CODE END 3 */

}

/** System Clock Configuration

*/

void SystemClock_Config(void)

{

RCC_ClkInitTypeDef RCC_ClkInitStruct;

RCC_PeriphCLKInitTypeDef PeriphClkInit;

RCC_OscInitTypeDef RCC_OscInitStruct;

__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 = 16;

RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;

RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;

RCC_OscInitStruct.PLL.PLLMUL = RCC_PLLMUL_6;

RCC_OscInitStruct.PLL.PLLDIV = RCC_PLLDIV_3;

HAL_RCC_OscConfig(&RCC_OscInitStruct);

RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;

RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;

RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;

RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;

RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1);

PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART2;

PeriphClkInit.Usart2ClockSelection = RCC_USART2CLKSOURCE_PCLK1;

HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit);

__SYSCFG_CLK_ENABLE();

}

/* USER CODE BEGIN 4 */

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)

{

if(huart->Instance == USART2)

{

memcpy(txBuffer,rxBuffer,RXSIZE);

HAL_UART_Receive_DMA(huart,rxBuffer,RXSIZE);

HAL_UART_Transmit_DMA(huart,txBuffer,TXSIZE);

}

}

void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)

{

}

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)

{

int32_t GyroValue;

Calc_AngleAccel();

GyroValue = Calc_AngleGyro();

ComplementFilter(GyroValue);

}

I2C.C

#include "i2c.h"

#include "gpio.h"

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

I2C_HandleTypeDef hi2cx;

/* I2C1 init function */

void MX_I2C1_Init(void)

{

hi2cx.Instance = I2C1;

hi2cx.Init.Timing = 0x20D22930;

hi2cx.Init.OwnAddress1 = 0;

hi2cx.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;

hi2cx.Init.DualAddressMode = I2C_DUALADDRESS_DISABLED;

hi2cx.Init.OwnAddress2 = 0;

hi2cx.Init.OwnAddress2Masks = I2C_OA2_NOMASK;

hi2cx.Init.GeneralCallMode = I2C_GENERALCALL_DISABLED;

hi2cx.Init.NoStretchMode = I2C_NOSTRETCH_DISABLED;

HAL_I2C_Init(&hi2cx);

/**Configure Analogue filter

*/

HAL_I2CEx_AnalogFilter_Config(&hi2cx, I2C_ANALOGFILTER_ENABLED);

}

void HAL_I2C_MspInit(I2C_HandleTypeDef* hi2c)

{

GPIO_InitTypeDef GPIO_InitStruct;

if(hi2c->Instance==I2C1)

{

/* Peripheral clock enable */

__I2C1_CLK_ENABLE();

/**I2C1 GPIO Configuration

PB6 ------> I2C1_SCL

PB7 ------> I2C1_SDA

*/

GPIO_InitStruct.Pin = GPIO_PIN_6|GPIO_PIN_7;

GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;

GPIO_InitStruct.Pull = GPIO_NOPULL;

GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;

GPIO_InitStruct.Alternate = GPIO_AF1_I2C1;

HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

}

void HAL_I2C_MspDeInit(I2C_HandleTypeDef* hi2c)

{

if(hi2c->Instance==I2C1)

{

/* Peripheral clock disable */

__I2C1_CLK_DISABLE();

/**I2C1 GPIO Configuration

PB6 ------> I2C1_SCL

PB7 ------> I2C1_SDA

*/

HAL_GPIO_DeInit(GPIOB, GPIO_PIN_6|GPIO_PIN_7);

}

}

-------------------------------------------------------------------------------传说中的分界线----------------------------------------------------------------------------

usart.c

#include "usart.h"

#include "gpio.h"

#include "dma.h"

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

UART_HandleTypeDef huart2;

DMA_HandleTypeDef hdma_usart2_rx;

DMA_HandleTypeDef hdma_usart2_tx;

/* USART2 init function */

void MX_USART2_UART_Init(void)

{

huart2.Instance = USART2;

huart2.Init.BaudRate = 9600;

huart2.Init.WordLength = UART_WORDLENGTH_8B;

huart2.Init.StopBits = UART_STOPBITS_1;

huart2.Init.Parity = UART_PARITY_NONE;

huart2.Init.Mode = UART_MODE_TX_RX;

huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;

huart2.Init.OverSampling = UART_OVERSAMPLING_16;

huart2.Init.OneBitSampling = UART_ONEBIT_SAMPLING_DISABLED;

huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;

HAL_UART_Init(&huart2);

}

void HAL_UART_MspInit(UART_HandleTypeDef* huart)

{

GPIO_InitTypeDef GPIO_InitStruct;

if(huart->Instance==USART2)

{

/* Peripheral clock enable */

__USART2_CLK_ENABLE();

/**USART2 GPIO Configuration

PA2 ------> USART2_TX

PA3 ------> USART2_RX

*/

GPIO_InitStruct.Pin = GPIO_PIN_2;

GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;

GPIO_InitStruct.Pull = GPIO_NOPULL;

GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;

GPIO_InitStruct.Alternate = GPIO_AF4_USART2;

HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

GPIO_InitStruct.Pin = GPIO_PIN_3;

GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;

GPIO_InitStruct.Pull = GPIO_NOPULL;

GPIO_InitStruct.Speed = GPIO_SPEED_LOW;

GPIO_InitStruct.Alternate = GPIO_AF4_USART2;

HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

/* Peripheral DMA init*/

hdma_usart2_rx.Instance = DMA1_Channel5;

hdma_usart2_rx.Init.Request = DMA_REQUEST_4;

hdma_usart2_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;

hdma_usart2_rx.Init.PeriphInc = DMA_PINC_DISABLE;

hdma_usart2_rx.Init.MemInc = DMA_MINC_ENABLE;

hdma_usart2_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;

hdma_usart2_rx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;

hdma_usart2_rx.Init.Mode = DMA_NORMAL;

hdma_usart2_rx.Init.Priority = DMA_PRIORITY_LOW;

HAL_DMA_Init(&hdma_usart2_rx);

__HAL_LINKDMA(huart,hdmarx,hdma_usart2_rx);

hdma_usart2_tx.Instance = DMA1_Channel4;

hdma_usart2_tx.Init.Request = DMA_REQUEST_4;

hdma_usart2_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;

hdma_usart2_tx.Init.PeriphInc = DMA_PINC_DISABLE;

hdma_usart2_tx.Init.MemInc = DMA_MINC_ENABLE;

hdma_usart2_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;

hdma_usart2_tx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;

hdma_usart2_tx.Init.Mode = DMA_NORMAL;

hdma_usart2_tx.Init.Priority = DMA_PRIORITY_LOW;

HAL_DMA_Init(&hdma_usart2_tx);

__HAL_LINKDMA(huart,hdmatx,hdma_usart2_tx);

}

}

void HAL_UART_MspDeInit(UART_HandleTypeDef* huart)

{

if(huart->Instance==USART2)

{

/* Peripheral clock disable */

__USART2_CLK_DISABLE();

/**USART2 GPIO Configuration

PA2 ------> USART2_TX

PA3 ------> USART2_RX

*/

HAL_GPIO_DeInit(GPIOA, GPIO_PIN_2|GPIO_PIN_3);

/* Peripheral DMA DeInit*/

HAL_DMA_DeInit(huart->hdmarx);

HAL_DMA_DeInit(huart->hdmatx);

}

}

-------------------------------------------------------------------------------传说中的分界线----------------------------------------------------------------------------

mpu6050.c

#include "stm32l0xx_hal.h"

#include "MPU6050.h"

//各坐标轴上静止偏差（重力，角速度）

int16_t offsetAccelX = -195;

int16_t offsetAccelY = 560;

int16_t offsetAccelZ = -169;

int16_t offsetGyroX = 12;

int16_t offsetGyroY = 33;

int16_t offsetGyroZ = 4;

extern I2C_HandleTypeDef hi2cx;

//**************************************

//向I2C设备写入一个字节数据

//**************************************

void Single_WriteI2C(uint8_t REG_Address,uint8_t REG_data)

{

uint8_t rxData[2] = {REG_Address,REG_data};

while(HAL_I2C_Master_Transmit(&hi2cx,SlaveAddress,rxData,2,5000) != HAL_OK)

{

if(HAL_I2C_GetError(&hi2cx) != HAL_I2C_ERROR_AF)

{}

}

}

//**************************************

//从I2C设备读取一个字节数据

//**************************************

uint8_t Single_ReadI2C(uint8_t REG_Address)

{

uint8_t REG_data;

while(HAL_I2C_Master_Transmit(&hi2cx,SlaveAddress,®_Address,1,5000) != HAL_OK)

{

if(HAL_I2C_GetError(&hi2cx) != HAL_I2C_ERROR_AF)

{}

}

if(HAL_I2C_Master_Receive(&hi2cx,SlaveAddress+1,®_data,1,5000) != HAL_OK)

{

if(HAL_I2C_GetError(&hi2cx) != HAL_I2C_ERROR_AF)

{}

}

return REG_data;

}

//**************************************

//初始化MPU6050

//**************************************

void InitMPU6050()

{

Single_WriteI2C(PWR_MGMT_1, 0x00); //解除休眠状态

Single_WriteI2C(SMPLRT_DIV, 0x07);

Single_WriteI2C(CONFIG, 0x06);

Single_WriteI2C(GYRO_CONFIG, 0x18);

Single_WriteI2C(ACCEL_CONFIG, 0x01);

}

//**************************************

//合成数据

//**************************************

int16_t GetMPUOutValue(uint8_t REG_Address)

{

int16_t result;

uint8_t H,L;

H=Single_ReadI2C(REG_Address);

L=Single_ReadI2C(REG_Address+1);

result = (H<<8)+L;

return result; //合成数据

}

//**************************************

//取某一轴上的加速度数据

//**************************************

int16_t GetAccelValue(char axis)

{

int16_t result = 0;

switch(axis)

{

case 'x':

case 'X':

{

result = GetMPUOutValue(ACCEL_XOUT_H) - offsetAccelX;

}

break;

case 'y':

case 'Y':

{

result = GetMPUOutValue(ACCEL_YOUT_H) - offsetAccelY;

}

break;

case 'z':

case 'Z':

{

result = GetMPUOutValue(ACCEL_ZOUT_H) - offsetAccelZ;

}

break;

}

return result;

}

//**************************************

//取某一轴上的角速度数据

//**************************************

int16_t GetGyroValue(char axis)

{

int16_t result = 0;

switch(axis)

{

case 'x':

case 'X':

{

result = GetMPUOutValue(GYRO_XOUT_H) - offsetGyroX;

}

break;

case 'y':

case 'Y':

{

result = GetMPUOutValue(GYRO_YOUT_H) - offsetGyroY;

}

break;

case 'z':

case 'Z':

{

result = GetMPUOutValue(GYRO_ZOUT_H) - offsetGyroZ;

}

break;

}

return result;

}

硬件连接

用Visual Scope输出的波型