STM32F4入手調(diào)試USART,ADC-DMA

如下STM32F4xxxx的USART初始化。

void USART1_AF_Config(void)

{

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

/* Connect PXx to USARTx_Tx*/

GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_USART1);

/* Connect PXx to USARTx_Rx*/

GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_USART1);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;//TX

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

GPIO_Init(GPIOB, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;//RX

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOB, &GPIO_InitStructure);

/* USARTx configured as follow:

- BaudRate = 115200 baud

- Word Length = 8 Bits

- One Stop Bit

- No parity

- Hardware flow control disabled (RTS and CTS signals)

- Receive and transmit enabled */

USART_InitStructure.USART_BaudRate = 115200;

USART_InitStructure.USART_WordLength = USART_WordLength_8b;

USART_InitStructure.USART_StopBits = USART_StopBits_1;

USART_InitStructure.USART_Parity = USART_Parity_No;

USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

USART_Init(USART1, &USART_InitStructure);

USART_ClockInitStructure.USART_Clock = USART_Clock_Disable;

USART_ClockInitStructure.USART_CPOL = USART_CPOL_Low;

USART_ClockInitStructure.USART_CPHA = USART_CPHA_2Edge;

USART_ClockInitStructure.USART_LastBit = USART_LastBit_Disable;

USART_Init(USART1, &USART_InitStructure);

USART_ClockInit(USART1, &USART_ClockInitStructure);

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

/* Enable USART */

USART_Cmd(USART1, ENABLE);

BSP_USART1_Init();

}

使用帶參數(shù)的USART Printf：

#define BSP_USART1_TX_FIFO_SIZE 1024

#define BSP_USART1_RX_FIFO_SIZE 128

void BSP_USART1_Init(void)

{

kfifo_alloc(&usart1_tx_fifo, BSP_USART1_TX_FIFO_SIZE);

kfifo_alloc(&usart1_rx_fifo, BSP_USART1_RX_FIFO_SIZE);

}

unsigned int BSP_USART1_Write(char* data, unsigned int len)

{

USART_ITConfig(USART1, USART_IT_TXE, DISABLE);

len = kfifo_in(&usart1_tx_fifo, (unsigned char*)data, len);

USART_ITConfig(USART1, USART_IT_TXE, ENABLE);

return len;

}

unsigned int BSP_USART1_Read(char* data, unsigned int len)

{

len = kfifo_out(&usart1_rx_fifo, (unsigned char*)data, len);

return len;

}

unsigned int BSP_USART1_Printf(char* fmt, ...)

{

va_list args;

unsigned int len;

char *buf = malloc(512);

va_start(args, fmt);

vsprintf(buf, fmt, args);

va_end(args);

len = BSP_USART1_Write(buf, strlen(buf));

free(buf);

return len;

}

Stm32f4xx_it.c中isr添加：

#include

#include

#include

extern struct kfifo usart1_tx_fifo;

extern struct kfifo usart1_rx_fifo;

void USART1_IRQHandler(void)

{

uint8_t chr;

if(USART_GetITStatus(USART1, USART_IT_RXNE))

{

chr = USART_ReceiveData(USART1);

kfifo_in(&usart1_rx_fifo, &chr, 1);

}

if(USART_GetITStatus(USART1, USART_IT_TXE))

{

USART_ClearITPendingBit(USART1, USART_IT_TXE);

if(kfifo_out(&usart1_tx_fifo, &chr, 1))

USART_SendData(USART1, chr);

else

USART_ITConfig(USART1, USART_IT_TXE, DISABLE);

}

}

主函數(shù)調(diào)用，在ADC3_DMA示例上進(jìn)行USART1的添加和使用，需要注意的是用fifo時發(fā)送和接收占用了1K多的內(nèi)存還有USART1_Printf也使用了0.5K的內(nèi)存，所以需要將heap的容量增大，改到0x800就夠。

int main(void)

{ USART1_AF_Config();

ADC3_CH12_DMA_Config();

/* Start ADC3 Software Conversion */

ADC_SoftwareStartConv(ADC3);

while (1)

{

/* convert the ADC value (from 0 to 0xFFF) to a voltage value (from 0V to 3.3V)*/

ADC3ConvertedVoltage = ADC3ConvertedValue *3300/0xFFF;

BSP_USART1_Printf("ADCdata: %drn",ADC3ConvertedVoltage);

Delay(0x3FFFFF);

BSP_USART1_Printf("%srn",dispstr);

}

}

STM32F4的DMA channel map也由原來F1的2維DMAx_Channely變成3維DMA_Channelx_DMAy_Streamz，增加了許多。

ADC的DMA全在DMA2上，通道0、1、2上。

/* DMA2 Stream0 channel0 configuration **************************************/