STM32F4入手調(diào)試USART,ADC-DMA
加入技術(shù)交流群
如下STM32F4xxxx的USART初始化。
本文引用地址：http://www.biyoush.com/article/201612/325060.htmvoid 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 **************************************/
評論