stm32f407简易示波器代码

以下是一个简单的基于STM32F407的示波器代码，使用ADC采样输入信号并在LCD上显示波形：

#include "stm32f4xx.h"
#include "stm32f4xx_adc.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_tim.h"
#include "stm32f4xx_usart.h"
#include "stm32f4xx_exti.h"
#include "stm32f4xx_syscfg.h"
#include "stm32f4xx_dma.h"
#include "misc.h"
#include "stdlib.h"
#include "stdio.h"

#define ADC1_DR_ADDRESS     ((uint32_t)0x4001204C)
#define ADC1_CHANNEL        ADC_Channel_0

uint16_t adc_buffer[1000];

void adc_init(void);
void lcd_init(void);
void lcd_write_cmd(uint8_t cmd);
void lcd_write_data(uint8_t data);
void lcd_write_string(char* str);
void lcd_set_cursor(uint8_t row, uint8_t col);
void lcd_clear(void);

int main(void)
{
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB | RCC_AHB1Periph_DMA2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_TIM1 | RCC_APB2Periph_TIM8 | RCC_APB2Periph_USART1, ENABLE);

    adc_init();
    lcd_init();

    while(1)
    {
        for(int i=0; i<1000; i++)
        {
            ADC_SoftwareStartConv(ADC1);
            while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC));
            adc_buffer[i] = ADC_GetConversionValue(ADC1);
        }

        lcd_clear();
        lcd_write_string("Waveform:");

        for(int i=0; i<1000; i++)
        {
            lcd_set_cursor(1, i % 16);
            lcd_write_data(adc_buffer[i] / 10);
        }
    }
}

void adc_init(void)
{
    ADC_InitTypeDef       ADC_InitStructure;
    ADC_CommonInitTypeDef ADC_CommonInitStructure;
    GPIO_InitTypeDef      GPIO_InitStructure;

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    RCC_APB2PeriphResetCmd(RCC_APB2Periph_ADC1, ENABLE);
    RCC_APB2PeriphResetCmd(RCC_APB2Periph_ADC1, DISABLE);

    ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
    ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
    ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
    ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
    ADC_CommonInit(&ADC_CommonInitStructure);

    ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStructure.ADC_ScanConvMode = DISABLE;
    ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
    ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
    ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T1_CC1;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_NbrOfConversion = 1;
    ADC_Init(ADC1, &ADC_InitStructure);

    ADC_RegularChannelConfig(ADC1, ADC1_CHANNEL, 1, ADC_SampleTime_3Cycles);

    ADC_Cmd(ADC1, ENABLE);
}

void lcd_init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    lcd_write_cmd(0x28); // 4-bit mode, 2 lines, 5x8 font
    lcd_write_cmd(0x0C); // display on, cursor off, blink off
    lcd_write_cmd(0x01); // clear display
    lcd_write_cmd(0x06); // cursor direction: right
}

void lcd_write_cmd(uint8_t cmd)
{
    GPIO_ResetBits(GPIOB, GPIO_Pin_12); // RS = 0 (command mode)
    GPIO_ResetBits(GPIOB, GPIO_Pin_13); // RW = 0 (write mode)
    GPIOB->ODR = (GPIOB->ODR & 0x00FF) | (cmd << 8); // send high nibble
    GPIO_SetBits(GPIOB, GPIO_Pin_14); // E = 1 (enable)
    GPIO_ResetBits(GPIOB, GPIO_Pin_14); // E = 0 (disable)
    GPIOB->ODR = (GPIOB->ODR & 0x00FF) | ((cmd & 0x0F) << 12); // send low nibble
    GPIO_SetBits(GPIOB, GPIO_Pin_14); // E = 1 (enable)
    GPIO_ResetBits(GPIOB, GPIO_Pin_14); // E = 0 (disable)
}

void lcd_write_data(uint8_t data)
{
    GPIO_SetBits(GPIOB, GPIO_Pin_12); // RS = 1 (data mode)
    GPIO_ResetBits(GPIOB, GPIO_Pin_13); // RW = 0 (write mode)
    GPIOB->ODR = (GPIOB->ODR & 0x00FF) | (data << 8); // send high nibble
    GPIO_SetBits(GPIOB, GPIO_Pin_14); // E = 1 (enable)
    GPIO_ResetBits(GPIOB, GPIO_Pin_14); // E = 0 (disable)
    GPIOB->ODR = (GPIOB->ODR & 0x00FF) | ((data & 0x0F) << 12); // send low nibble
    GPIO_SetBits(GPIOB, GPIO_Pin_14); // E = 1 (enable)
    GPIO_ResetBits(GPIOB, GPIO_Pin_14); // E = 0 (disable)
}

void lcd_write_string(char* str)
{
    while(*str)
    {
        lcd_write_data(*str++);
    }
}

void lcd_set_cursor(uint8_t row, uint8_t col)
{
    uint8_t address = (row == 0 ? 0x80 : 0xC0) + col;
    lcd_write_cmd(address);
}

void lcd_clear(void)
{
    lcd_write_cmd(0x01);
    lcd_write_cmd(0x02);
}

该代码使用PA0作为输入信号的ADC通道，每次采样1000个值，将其显示在16x2的LCD屏幕上。需要注意的是，该代码只是一个简单的示波器，采样速度和精度都可以进一步优化。