江科大STM32学习笔记

江科大STM32

STM32 简介

片上资源

系统结构

引脚定义

启动配置

最小系统电路

GPIO

GPIO基本结构

端口位结构

硬件电路的驱动方式

LED闪烁实验

int main(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    while (1)
    {
        GPIO_ResetBits(GPIOA, GPIO_Pin_0);
        Delay_ms(500);
        GPIO_SetBits(GPIOA, GPIO_Pin_0);
        Delay_ms(500);
        
        GPIO_WriteBit(GPIOA, GPIO_Pin_0, Bit_RESET);
        Delay_ms(500);
        GPIO_WriteBit(GPIOA, GPIO_Pin_0, Bit_SET);
        Delay_ms(500);
        
        GPIO_WriteBit(GPIOA, GPIO_Pin_0, (BitAction)0);
        Delay_ms(500);
        GPIO_WriteBit(GPIOA, GPIO_Pin_0, (BitAction)1);
        Delay_ms(500);
    }
}

LED流水灯

int main(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_All;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    while (1)
    {
        GPIO_Write(GPIOA, ~0x0001);	//0000 0000 0000 0001
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0002);	//0000 0000 0000 0010
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0004);	//0000 0000 0000 0100
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0008);	//0000 0000 0000 1000
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0010);	//0000 0000 0001 0000
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0020);	//0000 0000 0010 0000
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0040);	//0000 0000 0100 0000
        Delay_ms(100);
        GPIO_Write(GPIOA, ~0x0080);	//0000 0000 1000 0000
        Delay_ms(100);
    }
}

蜂鸣器

int main(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
    
    while (1)
    {
        GPIO_ResetBits(GPIOB, GPIO_Pin_12);
        Delay_ms(100);
        GPIO_SetBits(GPIOB, GPIO_Pin_12);
        Delay_ms(100);
        GPIO_ResetBits(GPIOB, GPIO_Pin_12);
        Delay_ms(100);
        GPIO_SetBits(GPIOB, GPIO_Pin_12);
        Delay_ms(700);
    }
}

环境搭建

新建工程

工程架构

GPIO输出

GPIO基本结构

GPIO端口位结构

GPIO输入

元器件上拉输入模式在没有输入时默认为低电平

按键控制LED

关键代码

void Key_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1 | GPIO_Pin_11;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
}

uint8_t Key_GetNum(void)
{
    uint8_t KeyNum = 0;
    if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_1) == 0)
    {
        Delay_ms(20);
        while (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_1) == 0);
        Delay_ms(20);
        KeyNum = 1;
    }
    if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_11) == 0)
    {
        Delay_ms(20);
        while (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_11) == 0);
        Delay_ms(20);
        KeyNum = 2;
    }
    
    return KeyNum;
}

光敏传感器控制蜂鸣器

关键代码

void LightSensor_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
}

uint8_t LightSensor_Get(void)
{
    return GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_13);
}

STM32 八种输入输出模式总结

1. GPIO_MODE_AIN 模拟输入

输入信号不经施密特触发器直接接入，输入信号为模拟量而非数字量，其余输入方式输入数字量。

2. GPIO_MODE_IN_FLOATING 浮空输入

输入信号经过施密特触发器接入输入数据存储器。当无信号输入时，电压不确定。因为浮空输入既高阻输入，可以认为输入端口阻抗无穷大，这样可以检测到微弱的信号。（相当于电压表测电压，如果电压表内阻不够大而外部阻抗比较大，则电压表分压会比较小）。此时输入高电平即高电平，输入低电平即低电平。但是外界没有输入时输入电平却容易受到外界电磁以及各种玄学干扰的影响。如按键采用浮空输入，则在按键按下时输入电平为低，但是当松开按键时输入端口悬空，外界有微弱的干扰都会被端口检测到。此时端口可能高，也可能低。

3. GPIO_MODE_IPD 下拉输入

浮空输入在外界没有输入时状态不确定，可能对电路造成干扰。为了使得电路更加稳定，不出现没有输入时端口的输入数据被干扰 （比如手碰一下电压就发生变化）。这时就需要下拉电阻（或上拉电阻）,此电阻与端口输入阻抗相比仍然较小。有输入信号时端口读取输入信号，无输入信号时端口电平被拉到低电平（高电平）。

4. GPIO_MODE_IPU 上拉输入

上拉输入与下拉输入类似，只是无输入信号时端口电平被拉到高电平。例如按键信号，当按下时输入低电平，松开时电平被拉到高电平。这样就不会出现按键松开时端口电平不确定的情况。即不知道时按下还是松开。

5. GPIO-MODE_OUT_OD 开漏输出

开漏输出即漏极开路输出。这种输出方式指场效应管漏极开路输出。需要接上拉电阻才能输出1。漏极经上拉电阻接到电源，栅极输出0时，场效应管截止（阻抗无线大），电压被分到场效应管上，此时输出为1。当栅极输出1时，场效应管导通，输出端口相当于接地，此时输出0。开漏输出高电平时是由外接电源输出的，因此可以实现高于输出端口电压的输出。可以实现电平的转换。开漏输出可以实现线与功能，方法是多个输出共接一个上拉电阻。但是漏极开路输出上升沿慢，因为上升沿是外接电源对上拉电阻以及外接负载充电。当上拉电阻较大或者负载容性较大时时间常数较大，充电较慢。需要较快反映时可以采用下降沿触发，此时没有电阻接入，电路的时间常数较小，充电较快。

6. GPIO_MODE_OUT_PP 推挽输出

推挽输出既可以输出1，又可以输出0。但是无法调节输出电压，因为输出高低电平均为三极管输入端电压，此电压在由芯片内部供电，无法改变。推挽输出任意时刻只有一路工作。上图为输出高电平时电路工作状态。只有三极管导通电阻，无外接电阻。因此推挽输出损耗小、速度快。

7. GPIO_MODE_AF_OD 复用开漏输出

STM32单片机内部有其他的外设，比如定时器、DAC等。复用开漏输出与普通开漏输出区别在于，开漏输出输出的是输出数据寄存器中的数据，复用开漏输出输出的是来自外设的数据。

8. GOIO_MODE_AF_PP 复用推挽输出

复用推挽输出原理与复用开漏输出原理相同

OLED调试驱动

中断系统

NVIC嵌套中断向量控制器

EXTI外部中断

配置外设中断的基本流程:

1. 配置RCC, 打开涉及的外设时钟
2. 配置GPIO
3. 配置AFIO
4. 配置EXTI
5. 配置NVIC

AFIO复用IO口

旋转编码器

红外传感器计次

void CountSensor_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
    
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource14);
    
    EXTI_InitTypeDef EXTI_InitStructure;
    EXTI_InitStructure.EXTI_Line = EXTI_Line14;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_Init(&EXTI_InitStructure);
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_Init(&NVIC_InitStructure);
}

uint16_t CountSensor_Get(void)
{
    return CountSensor_Count;
}

void EXTI15_10_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line14) == SET)
    {
        /*如果出现数据乱跳的现象<span class="bd-box"><h-char class="bd bd-beg"><h-inner>，</h-inner></h-char></span>可再次判断引脚电平<span class="bd-box"><h-char class="bd bd-beg"><h-inner>，</h-inner></h-char></span>以避免抖动*/
        if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_14) == 0)
        {
            CountSensor_Count ++;
        }
        EXTI_ClearITPendingBit(EXTI_Line14);
    }
}

STM32中 中断函数的名字是固定的, 参见start文件中的定义

旋转编码器计次

void Encoder_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
    
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource0);
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource1);
    
    EXTI_InitTypeDef EXTI_InitStructure;
    EXTI_InitStructure.EXTI_Line = EXTI_Line0 | EXTI_Line1;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_Init(&EXTI_InitStructure);
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
    NVIC_Init(&NVIC_InitStructure);
}

int16_t Encoder_Get(void)
{
    int16_t Temp;
    Temp = Encoder_Count;
    Encoder_Count = 0;
    return Temp;
}

void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) == SET)
    {
        /*如果出现数据乱跳的现象<span class="bd-box"><h-char class="bd bd-beg"><h-inner>，</h-inner></h-char></span>可再次判断引脚电平<span class="bd-box"><h-char class="bd bd-beg"><h-inner>，</h-inner></h-char></span>以避免抖动*/
        if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_0) == 0)
        {
            if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_1) == 0)
            {
                Encoder_Count --;
            }
        }
        EXTI_ClearITPendingBit(EXTI_Line0);
    }
}

void EXTI1_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line1) == SET)
    {
        /*如果出现数据乱跳的现象<span class="bd-box"><h-char class="bd bd-beg"><h-inner>，</h-inner></h-char></span>可再次判断引脚电平<span class="bd-box"><h-char class="bd bd-beg"><h-inner>，</h-inner></h-char></span>以避免抖动*/
        if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_1) == 0)
        {
            if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_0) == 0)
            {
                Encoder_Count ++;
            }
        }
        EXTI_ClearITPendingBit(EXTI_Line1);
    }
}

STM32中 中断函数的名字是固定的, 参见start文件中的定义

__Vectors       DCD     __initial_sp               ; Top of Stack
                DCD     Reset_Handler              ; Reset Handler
                DCD     NMI_Handler                ; NMI Handler
                DCD     HardFault_Handler          ; Hard Fault Handler
                DCD     MemManage_Handler          ; MPU Fault Handler
                DCD     BusFault_Handler           ; Bus Fault Handler
                DCD     UsageFault_Handler         ; Usage Fault Handler
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     SVC_Handler                ; SVCall Handler
                DCD     DebugMon_Handler           ; Debug Monitor Handler
                DCD     0                          ; Reserved
                DCD     PendSV_Handler             ; PendSV Handler
                DCD     SysTick_Handler            ; SysTick Handler

                ; External Interrupts
                DCD     WWDG_IRQHandler            ; Window Watchdog
                DCD     PVD_IRQHandler             ; PVD through EXTI Line detect
                DCD     TAMPER_IRQHandler          ; Tamper
                DCD     RTC_IRQHandler             ; RTC
                DCD     FLASH_IRQHandler           ; Flash
                DCD     RCC_IRQHandler             ; RCC
                DCD     EXTI0_IRQHandler           ; EXTI Line 0
                DCD     EXTI1_IRQHandler           ; EXTI Line 1
                DCD     EXTI2_IRQHandler           ; EXTI Line 2
                DCD     EXTI3_IRQHandler           ; EXTI Line 3
                DCD     EXTI4_IRQHandler           ; EXTI Line 4
                DCD     DMA1_Channel1_IRQHandler   ; DMA1 Channel 1
                DCD     DMA1_Channel2_IRQHandler   ; DMA1 Channel 2
                DCD     DMA1_Channel3_IRQHandler   ; DMA1 Channel 3
                DCD     DMA1_Channel4_IRQHandler   ; DMA1 Channel 4
                DCD     DMA1_Channel5_IRQHandler   ; DMA1 Channel 5
                DCD     DMA1_Channel6_IRQHandler   ; DMA1 Channel 6
                DCD     DMA1_Channel7_IRQHandler   ; DMA1 Channel 7
                DCD     ADC1_2_IRQHandler          ; ADC1_2
                DCD     USB_HP_CAN1_TX_IRQHandler  ; USB High Priority or CAN1 TX
                DCD     USB_LP_CAN1_RX0_IRQHandler ; USB Low  Priority or CAN1 RX0
                DCD     CAN1_RX1_IRQHandler        ; CAN1 RX1
                DCD     CAN1_SCE_IRQHandler        ; CAN1 SCE
                DCD     EXTI9_5_IRQHandler         ; EXTI Line 9..5
                DCD     TIM1_BRK_IRQHandler        ; TIM1 Break
                DCD     TIM1_UP_IRQHandler         ; TIM1 Update
                DCD     TIM1_TRG_COM_IRQHandler    ; TIM1 Trigger and Commutation
                DCD     TIM1_CC_IRQHandler         ; TIM1 Capture Compare
                DCD     TIM2_IRQHandler            ; TIM2
                DCD     TIM3_IRQHandler            ; TIM3
                DCD     TIM4_IRQHandler            ; TIM4
                DCD     I2C1_EV_IRQHandler         ; I2C1 Event
                DCD     I2C1_ER_IRQHandler         ; I2C1 Error
                DCD     I2C2_EV_IRQHandler         ; I2C2 Event
                DCD     I2C2_ER_IRQHandler         ; I2C2 Error
                DCD     SPI1_IRQHandler            ; SPI1
                DCD     SPI2_IRQHandler            ; SPI2
                DCD     USART1_IRQHandler          ; USART1
                DCD     USART2_IRQHandler          ; USART2
                DCD     USART3_IRQHandler          ; USART3
                DCD     EXTI15_10_IRQHandler       ; EXTI Line 15..10
                DCD     RTCAlarm_IRQHandler        ; RTC Alarm through EXTI Line
                DCD     USBWakeUp_IRQHandler       ; USB Wakeup from suspend

定时器TIM

定时中断

定时器时序

RCC时钟树

定时器定时中断

void Timer_Init(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    
    TIM_InternalClockConfig(TIM2);
    
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInitStructure.TIM_Period = 10000 - 1;
    TIM_TimeBaseInitStructure.TIM_Prescaler = 7200 - 1;
    TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);
    
    TIM_ClearFlag(TIM2, TIM_FLAG_Update);
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_Init(&NVIC_InitStructure);
    
    TIM_Cmd(TIM2, ENABLE);
}

/*
void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) == SET)
    {
        
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
    }
}
*/

定时器外部时钟

用IO口模拟外部时钟源

void Timer_Init(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    TIM_ETRClockMode2Config(TIM2, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0x0F);
    
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInitStructure.TIM_Period = 10 - 1;
    TIM_TimeBaseInitStructure.TIM_Prescaler = 1 - 1;
    TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);
    
    TIM_ClearFlag(TIM2, TIM_FLAG_Update);
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_Init(&NVIC_InitStructure);
    
    TIM_Cmd(TIM2, ENABLE);
}

uint16_t Timer_GetCounter(void)
{
    return TIM_GetCounter(TIM2);
}

/*
void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) == SET)
    {
        
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
    }
}
*/

TIM输出比较

(相当于把PWM当成通讯协议来用, 舵机里面自带驱动电路)

PWM驱动实验

void PWM_Init(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
//	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
//	GPIO_PinRemapConfig(GPIO_PartialRemap1_TIM2, ENABLE);
//	GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;		//GPIO_Pin_15;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    TIM_InternalClockConfig(TIM2);
    
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInitStructure.TIM_Period = 100 - 1;		//ARR
    TIM_TimeBaseInitStructure.TIM_Prescaler = 720 - 1;		//PSC
    TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);
    
    TIM_OCInitTypeDef TIM_OCInitStructure;
    TIM_OCStructInit(&TIM_OCInitStructure);
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = 0;		//CCR
    TIM_OC1Init(TIM2, &TIM_OCInitStructure);
    
    TIM_Cmd(TIM2, ENABLE);
}

void PWM_SetCompare1(uint16_t Compare)
{
    TIM_SetCompare1(TIM2, Compare);
}

TIM输入捕获

测频法适合高频, 测周法适合低频, 以中界频率为界

PWMI模式测频率/占空比

void IC_Init(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    TIM_InternalClockConfig(TIM3);
    
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInitStructure.TIM_Period = 65536 - 1;		//ARR
    TIM_TimeBaseInitStructure.TIM_Prescaler = 72 - 1;		//PSC
    TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseInitStructure);
    
    TIM_ICInitTypeDef TIM_ICInitStructure;
    TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
    TIM_ICInitStructure.TIM_ICFilter = 0xF;
    TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
    TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
    TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
    TIM_PWMIConfig(TIM3, &TIM_ICInitStructure);

    TIM_SelectInputTrigger(TIM3, TIM_TS_TI1FP1);
    TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Reset);
    
    TIM_Cmd(TIM3, ENABLE);
}

uint32_t IC_GetFreq(void)
{
    return 1000000 / (TIM_GetCapture1(TIM3) + 1);
}

uint32_t IC_GetDuty(void)
{
    return (TIM_GetCapture2(TIM3) + 1) * 100 / (TIM_GetCapture1(TIM3) + 1);
}

编码器接口

编码器接口测速

void Encoder_Init(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
        
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInitStructure.TIM_Period = 65536 - 1;		//ARR
    TIM_TimeBaseInitStructure.TIM_Prescaler = 1 - 1;		//PSC
    TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseInitStructure);
    
    TIM_ICInitTypeDef TIM_ICInitStructure;
    TIM_ICStructInit(&TIM_ICInitStructure);
    TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
    TIM_ICInitStructure.TIM_ICFilter = 0xF;
    TIM_ICInit(TIM3, &TIM_ICInitStructure);
    TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
    TIM_ICInitStructure.TIM_ICFilter = 0xF;
    TIM_ICInit(TIM3, &TIM_ICInitStructure);
    
    TIM_EncoderInterfaceConfig(TIM3, TIM_EncoderMode_TI12, TIM_ICPolarity_Rising, TIM_ICPolarity_Rising);
    
    TIM_Cmd(TIM3, ENABLE);
}

int16_t Encoder_Get(void)
{
    int16_t Temp;
    Temp = TIM_GetCounter(TIM3);
    TIM_SetCounter(TIM3, 0);
    return Temp;
}

ADC模数转换

ADC基本结构

输入通道

转换模式

• 单次转换，非扫描模式
• 连续转换，非扫描模式
  
• 单次转换，扫描模式
  
• 连续转换，扫描模式
  
• …

AD单通道

void AD_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    RCC_ADCCLKConfig(RCC_PCLK2_Div6);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_55Cycles5);
    
    ADC_InitTypeDef ADC_InitStructure;
    ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
    ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
    ADC_InitStructure.ADC_ScanConvMode = DISABLE;
    ADC_InitStructure.ADC_NbrOfChannel = 1;
    ADC_Init(ADC1, &ADC_InitStructure);
    
    ADC_Cmd(ADC1, ENABLE);
    
    ADC_ResetCalibration(ADC1);
    while (ADC_GetResetCalibrationStatus(ADC1) == SET);
    ADC_StartCalibration(ADC1);
    while (ADC_GetCalibrationStatus(ADC1) == SET);
}

uint16_t AD_GetValue(void)
{
    ADC_SoftwareStartConvCmd(ADC1, ENABLE);
    while (ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC) == RESET);
    return ADC_GetConversionValue(ADC1);
}

DMA

高位补零/高位舍弃

DMA数据转运

ADC扫描模式+DMA

存储器映像

DMA工作的条件

1. 转运计数器大于0
2. 触发源有触发信号
3. DMA使能

DMA数据转运

uint16_t MyDMA_Size;

void MyDMA_Init(uint32_t AddrA, uint32_t AddrB, uint16_t Size)
{
    MyDMA_Size = Size;
    
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
    
    DMA_InitTypeDef DMA_InitStructure;
    DMA_InitStructure.DMA_PeripheralBaseAddr = AddrA;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Enable;
    DMA_InitStructure.DMA_MemoryBaseAddr = AddrB;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
    DMA_InitStructure.DMA_BufferSize = Size;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
    DMA_InitStructure.DMA_M2M = DMA_M2M_Enable;
    DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
    DMA_Init(DMA1_Channel1, &DMA_InitStructure);
    
    DMA_Cmd(DMA1_Channel1, DISABLE);
}

void MyDMA_Transfer(void)
{
    DMA_Cmd(DMA1_Channel1, DISABLE);
    DMA_SetCurrDataCounter(DMA1_Channel1, MyDMA_Size);
    DMA_Cmd(DMA1_Channel1, ENABLE);
    
    while (DMA_GetFlagStatus(DMA1_FLAG_TC1) == RESET);
    DMA_ClearFlag(DMA1_FLAG_TC1);
}

DMA+AD多通道

uint16_t AD_Value[4];

void AD_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
    
    RCC_ADCCLKConfig(RCC_PCLK2_Div6);
    
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_55Cycles5);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_55Cycles5);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 3, ADC_SampleTime_55Cycles5);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 4, ADC_SampleTime_55Cycles5);
        
    ADC_InitTypeDef ADC_InitStructure;
    ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
    ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
    ADC_InitStructure.ADC_ScanConvMode = ENABLE;
    ADC_InitStructure.ADC_NbrOfChannel = 4;
    ADC_Init(ADC1, &ADC_InitStructure);
    
    DMA_InitTypeDef DMA_InitStructure;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&ADC1->DR;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)AD_Value;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
    DMA_InitStructure.DMA_BufferSize = 4;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
    DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
    DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
    DMA_Init(DMA1_Channel1, &DMA_InitStructure);
    
    DMA_Cmd(DMA1_Channel1, ENABLE);
    ADC_DMACmd(ADC1, ENABLE);
    ADC_Cmd(ADC1, ENABLE);
    
    ADC_ResetCalibration(ADC1);
    while (ADC_GetResetCalibrationStatus(ADC1) == SET);
    ADC_StartCalibration(ADC1);
    while (ADC_GetCalibrationStatus(ADC1) == SET);
    
    ADC_SoftwareStartConvCmd(ADC1, ENABLE);
}

串口通信

USART

串口发送+接收

void Serial_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
        
    GPIO_InitTypeDef GPIO_Structure;
    GPIO_Structure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_9;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_Structure);
    
    GPIO_Structure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_10;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_Structure);
    
    USART_InitTypeDef USART_InitStructure;
    USART_InitStructure.USART_BaudRate = 9600;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
    USART_InitStructure.USART_Parity = USART_Parity_No;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_Init(USART1, &USART_InitStructure);
    
    USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_Init(&NVIC_InitStructure);
    
    USART_Cmd(USART1, ENABLE);
    
}

void Serial_ByteSend(uint8_t byte)
{
    USART_SendData(USART1, byte);
    while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET); 
    
}

//printf的移植
void Serial_Printf(char *format, ...)
{
    char String[100];
    va_list arg;
    va_start(arg, format);
    vsprintf(String, format, arg);
    va_end(arg);
    Serial_SendString(String);
}

Hex/文本数据包

数据包接收

串口发送文本数据包

状态机核心代码

void USART1_IRQHandler(void)
{
    static uint8_t RxState = 0;
    static uint8_t pRxPacket = 0;
    if(USART_GetITStatus(USART1, USART_IT_RXNE) == SET)
    {
        
        uint8_t RxData = USART_ReceiveData(USART1);
        if(RxState == 0)
        {
            if(RxData == '@')
            {
                RxState = 1;
                pRxPacket = 0;
            }
        }
        else if(RxState == 1)
        {
            if(RxData == '\r')
            {
                RxState = 2;
            }
            
            else
            {		
                Serial_RxPacket[pRxPacket] = RxData;
                pRxPacket ++;
            }

        }
        else if(RxState == 2)
        {
            if(RxData == '\n')
            {
                RxState = 0;
                Serial_RxPacket[pRxPacket] = '\0';
                Serial_RxFlag = 1;
            }
        }
        
        USART_ClearITPendingBit(USART1, USART_IT_RXNE);
    }
}

I2C通信

I2C时序单元

I2C时序

MPU6050

软件I2C读写MPU6050

控制电平

//引脚初始化
void MyI2C_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    
    GPIO_InitTypeDef GPIO_Structure;
    GPIO_Structure.GPIO_Mode = GPIO_Mode_Out_OD;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_Structure);
    
    GPIO_SetBits(GPIOB, GPIO_Pin_10 | GPIO_Pin_11);
}

//控制引脚电平
void MyI2C_W_SCL(uint8_t BitValue)
{
    GPIO_WriteBit(GPIOB, GPIO_Pin_10, (BitAction)BitValue);
    Delay_us(10);
}

void MyI2C_W_SDA(uint8_t BitValue)
{
    GPIO_WriteBit(GPIOB, GPIO_Pin_11, (BitAction)BitValue);
    Delay_us(10);
}

uint8_t MyI2C_R_SDA(void)
{
    uint8_t BitValue;
    BitValue = GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_11);
    Delay_us(10);
    return BitValue;
}

I2C基本时序单元

void MyI2C_Start(void)
{
    //释放SDA 和 SCL
    MyI2C_W_SCL(1);
    MyI2C_W_SDA(1);
    
    //i2c起始逻辑
    MyI2C_W_SDA(0);
    MyI2C_W_SCL(0);

}

void MyI2C_Stop(void)
{
    MyI2C_W_SDA(0);
    MyI2C_W_SCL(1);
    MyI2C_W_SDA(1);
}

void MyI2C_SendByte(uint8_t Byte)
{
    uint8_t i = 0;
    for(i=0; i<8; i++)
    {
        MyI2C_W_SDA(Byte & (0x80 >> i));
        MyI2C_W_SCL(1);
        MyI2C_W_SCL(0);
    }
}

uint8_t MyI2C_ReceiveByte(void)
{
    uint8_t i, Byte = 0x00;
    MyI2C_W_SDA(1);
    for(i=0; i<8; i++)
    {
        MyI2C_W_SCL(1);
        if(MyI2C_R_SDA() == 1) {Byte |= (0x80 >> i);}
        MyI2C_W_SCL(0);
    }
    return Byte;
}

void MyI2C_SendAck(uint8_t AckBit)
{
    MyI2C_W_SDA(AckBit);
    MyI2C_W_SCL(1);
    MyI2C_W_SCL(0);
}

uint8_t MyI2C_ReceiveAck(void)
{
    uint8_t AckBit;
    MyI2C_W_SDA(1);
    MyI2C_W_SCL(1);
    AckBit = MyI2C_R_SDA();
    MyI2C_W_SCL(0);
    return AckBit;
}

I2C时序

void MPU6050_WriteReg(uint8_t RegAddr, uint8_t Data)
{
    MyI2C_Start();
    MyI2C_SendByte(MPU6050_ADDR);
    MyI2C_ReceiveAck();
    MyI2C_SendByte(RegAddr);
    MyI2C_ReceiveAck();
    MyI2C_SendByte(Data);
    MyI2C_ReceiveAck();
    MyI2C_Stop();
}

uint8_t MPU6050_ReadReg(uint8_t RegAddr)
{
    uint8_t Data;
    
    MyI2C_Start();
    MyI2C_SendByte(MPU6050_ADDR);
    MyI2C_ReceiveAck();
    MyI2C_SendByte(RegAddr);
    MyI2C_ReceiveAck();
    
    MyI2C_Start();
    MyI2C_SendByte(MPU6050_ADDR | 0x01);
    MyI2C_ReceiveAck();
    Data = MyI2C_ReceiveByte();
    MyI2C_SendAck(1);
    MyI2C_Stop();
    
    return Data;
}

MPU6050

void MPU6050_Init(void)
{
    MyI2C_Init();
    MPU6050_WriteReg(MPU6050_PWR_MGMT_1, 0x01);
    MPU6050_WriteReg(MPU6050_PWR_MGMT_2, 0x00);
    MPU6050_WriteReg(MPU6050_SMPLRT_DIV, 0x09);
    MPU6050_WriteReg(MPU6050_CONFIG, 0x06);
    MPU6050_WriteReg(MPU6050_GYRO_CONFIG, 0x18);
    MPU6050_WriteReg(MPU6050_ACCEL_CONFIG, 0x18);
}

uint8_t MPU6050_GetID(void)
{
    return MPU6050_ReadReg(MPU6050_WHO_AM_I);
}


void MPU6050_GetData(int16_t *AccX, int16_t *AccY, int16_t *AccZ,  \
                     int16_t *GyroX, int16_t *GyroY, int16_t *GyroZ)
{
    uint16_t DataH, DataL;
    
    DataH = MPU6050_ReadReg(MPU6050_ACCEL_XOUT_H);
    DataL = MPU6050_ReadReg(MPU6050_ACCEL_XOUT_L);
    *AccX  = (DataH << 8) | (DataL);
    
    DataH = MPU6050_ReadReg(MPU6050_ACCEL_YOUT_H);
    DataL = MPU6050_ReadReg(MPU6050_ACCEL_YOUT_L);
    *AccY  = (DataH << 8) | (DataL);
    
    DataH = MPU6050_ReadReg(MPU6050_ACCEL_ZOUT_H);
    DataL = MPU6050_ReadReg(MPU6050_ACCEL_ZOUT_L);
    *AccZ  = (DataH << 8) | (DataL);
    
    DataH = MPU6050_ReadReg(MPU6050_GYRO_XOUT_H);
    DataL = MPU6050_ReadReg(MPU6050_GYRO_XOUT_L);
    *GyroX = (DataH << 8) | (DataL);
    
    DataH = MPU6050_ReadReg(MPU6050_GYRO_YOUT_H);
    DataL = MPU6050_ReadReg(MPU6050_GYRO_YOUT_L);
    *GyroY = (DataH << 8) | (DataL);
    
    DataH = MPU6050_ReadReg(MPU6050_GYRO_ZOUT_H);
    DataL = MPU6050_ReadReg(MPU6050_GYRO_ZOUT_L);
    *GyroZ = (DataH << 8) | (DataL);

}

STM32 I2C外设

传送流程

I2C外设实验

硬件部分核心代码（业务逻辑层保持不变）

void MPU6050_WriteReg(uint8_t RegAddr, uint8_t Data)
{

    I2C_GenerateSTART(I2C2, ENABLE);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS);
    
    I2C_Send7bitAddress(I2C2, MPU6050_ADDR, I2C_Direction_Transmitter);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED) != SUCCESS);
    
    I2C_SendData(I2C2, RegAddr);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTING) != SUCCESS);

    I2C_SendData(I2C2, Data);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED) != SUCCESS);

    I2C_GenerateSTOP(I2C2, ENABLE);
}

uint8_t MPU6050_ReadReg(uint8_t RegAddr)
{
    uint8_t Data;

    I2C_GenerateSTART(I2C2, ENABLE);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS);
    
    I2C_Send7bitAddress(I2C2, MPU6050_ADDR, I2C_Direction_Transmitter);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED) != SUCCESS);
    
    I2C_SendData(I2C2, RegAddr);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTING) != SUCCESS);

    I2C_GenerateSTART(I2C2, ENABLE);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS);

    I2C_Send7bitAddress(I2C2, MPU6050_ADDR, I2C_Direction_Receiver);
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED) != SUCCESS);
    
    I2C_AcknowledgeConfig(I2C2, DISABLE);
    I2C_GenerateSTOP(I2C2, ENABLE);
    
    while (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_RECEIVED) != SUCCESS);
    Data = I2C_ReceiveData(I2C2);
    
    return Data;
}

void MPU6050_Init(void)
{
//	MyI2C_Init();
    
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    
    GPIO_InitTypeDef GPIO_Structure;
    GPIO_Structure.GPIO_Mode = GPIO_Mode_AF_OD;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_Structure);
    
    GPIO_Init(GPIOB, &GPIO_Structure);
    
    I2C_InitTypeDef I2C_InitStructure;
    I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
    I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
    I2C_InitStructure.I2C_ClockSpeed = 50000;
    I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
    I2C_InitStructure.I2C_OwnAddress1 = 0x00;
    I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
    I2C_Init(I2C2, &I2C_InitStructure);
    
    I2C_Cmd(I2C2, ENABLE);

    
    MPU6050_WriteReg(MPU6050_PWR_MGMT_1, 0x01);
    MPU6050_WriteReg(MPU6050_PWR_MGMT_2, 0x00);
    MPU6050_WriteReg(MPU6050_SMPLRT_DIV, 0x09);
    MPU6050_WriteReg(MPU6050_CONFIG, 0x06);
    MPU6050_WriteReg(MPU6050_GYRO_CONFIG, 0x18);
    MPU6050_WriteReg(MPU6050_ACCEL_CONFIG, 0x18);
}

SPI通信

基本时序单元

SPI时序

W25Q64简介

Flash操作事项

SPI软件读写实验

对电平操作的封装

void MySPI_W_SS(uint8_t bitValue)
{
    GPIO_WriteBit(GPIOA, GPIO_Pin_4, (BitAction)bitValue);
}

void MySPI_W_SCK(uint8_t bitValue)
{
    GPIO_WriteBit(GPIOA, GPIO_Pin_5, (BitAction)bitValue);
}

void MySPI_W_MOSI(uint8_t bitValue)
{
    GPIO_WriteBit(GPIOA, GPIO_Pin_7, (BitAction)bitValue);
}

uint8_t MySPI_R_MISO(void)
{
    return GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_6);
}

SPI时序

void MySPI_Start(void)
{
    MySPI_W_SS(0);
}

void MySPI_Stop(void)
{
    MySPI_W_SS(1);
}

uint8_t MySPI_SwapByte(uint8_t ByteSend)
{
    uint8_t ByteRecive=0x00;
    
    uint8_t i;
    for(i=0; i<8; i++)
    {
        MySPI_W_MOSI(ByteSend & (0x80 >> i));
        MySPI_W_SCK(1);
        if(MySPI_R_MISO() == 1)
        {
            ByteRecive |= (0x80 >> i);
        }
        MySPI_W_SCK(0);
    }
    
    return ByteRecive;
}

W25Q64操作时序

void W25Q64_Init(void)
{
    MySPI_Init();
}

void W25Q64_ReadID(uint8_t *MID, uint16_t *DID)
{
    MySPI_Start();
    MySPI_SwapByte(W25Q64_JEDEC_ID);
    *MID = MySPI_SwapByte(W25Q64_DUMMY_BYTE);
    *DID = MySPI_SwapByte(W25Q64_DUMMY_BYTE);
    *DID <<= 8; 	//*DID = *DID << 8;
    *DID |= MySPI_SwapByte(W25Q64_DUMMY_BYTE);
    MySPI_Stop();
}

void W25Q64_WriteEnable(void)
{
    MySPI_Start();
    MySPI_SwapByte(W25Q64_WRITE_ENABLE);
    MySPI_Stop();
}

void W25Q64_WaitBusy(void)
{
    MySPI_Start();
    MySPI_SwapByte(W25Q64_READ_STATUS_REGISTER_1);
    uint32_t Timeout = 100000;
    while((MySPI_SwapByte(W25Q64_DUMMY_BYTE) & 0x01) == 0x01)
    {
        Timeout --;
        if(Timeout==0) break;
    }
    MySPI_Stop();
}

void W25Q64_PageProgram(uint32_t Address ,uint8_t *DataArray, uint16_t count)
{
    W25Q64_WriteEnable();
    
    MySPI_Start();
    MySPI_SwapByte(W25Q64_PAGE_PROGRAM);
    MySPI_SwapByte(Address>>16);
    MySPI_SwapByte(Address>>8);
    MySPI_SwapByte(Address);
    
    uint16_t i=0;
    for(i=0; i<count; i++)
    {
        MySPI_SwapByte(DataArray[i]);
    }
    MySPI_Stop();
    W25Q64_WaitBusy();
    
}

void W25Q64_SectorErase(uint32_t Address)
{
    W25Q64_WriteEnable();
    
    MySPI_Start();
    MySPI_SwapByte(W25Q64_SECTOR_ERASE_4KB);
    MySPI_SwapByte(Address>>16);
    MySPI_SwapByte(Address>>8);
    MySPI_SwapByte(Address);
    MySPI_Stop();
    
    W25Q64_WaitBusy();
    
}

void W25Q64_ReadData(uint32_t Address, uint8_t *DataArray, uint32_t Count)
{
    uint32_t i;
    MySPI_Start();
    MySPI_SwapByte(W25Q64_READ_DATA);
    MySPI_SwapByte(Address>>16);
    MySPI_SwapByte(Address>>8);
    MySPI_SwapByte(Address);
    for(i=0; i<Count; i++)
    {
        DataArray[i] = MySPI_SwapByte(W25Q64_DUMMY_BYTE);
    }
    MySPI_Stop();
    
}

SPI外设

SPI硬件通信实验

通信逻辑方面不变, 改变的是底层通信的代码, 用硬件电路实现
改变了2个函数MySPI_Init uint8_t MySPI_SwapByte(uint8_t ByteSend) `

void MySPI_W_SS(uint8_t bitValue)
{
    GPIO_WriteBit(GPIOA, GPIO_Pin_4, (BitAction)bitValue);
}

void MySPI_Init(void)
{
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
    
    GPIO_InitTypeDef GPIO_Structure;
    GPIO_Structure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_4;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_Structure);
    
    GPIO_Structure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_Structure);

    GPIO_Structure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Structure.GPIO_Pin = GPIO_Pin_6;
    GPIO_Structure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_Structure);
    
    SPI_InitTypeDef SPI_InitStructure;
    SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_128;
    SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
    SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
    SPI_InitStructure.SPI_CRCPolynomial = 7;
    SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
    SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
    SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
    SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
    SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
    SPI_Init(SPI1, &SPI_InitStructure);
    
    SPI_Cmd(SPI1, ENABLE);
    
    MySPI_W_SS(1);
}

void MySPI_Start(void)
{
    MySPI_W_SS(0);
}

void MySPI_Stop(void)
{
    MySPI_W_SS(1);
}

uint8_t MySPI_SwapByte(uint8_t ByteSend)
{
    while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) != SET);
    SPI_I2S_SendData(SPI1, ByteSend);
    while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) != SET);
    return SPI_I2S_ReceiveData(SPI1);
}