引言：
本文利用STM32F4设计制作了一个双路低频信号发生器。
能够完成以下功能：
(1) 两路信号发生器可选择输出正弦波、方波，频率连续可调，范围为 1kHz 到 10kHz，每路信号的波形及频率可单独设置。
(2) 输出正弦信号的电压峰峰值 VPP 范围为 0.1~5V 且两路信号幅度可单独设置。
(3) 具有显示输出信号波形和相应参数（幅度、频率等）的功能.。
(4) 输出的两路方波信号占空比 10%到 90%单独可调。
完整代码请参考：https://github.com/PPPerry/Dual-low-frequency-signal-generator
1.硬件模块
电源采用 5V 实验电源供电
独立按键按键输入
TFTLCD电容触摸屏触摸输入
STM32F407探索者开发板
2.软件模块
顶层代码：
#include "sys.h"
#include "dac.h"
#include "lcd.h"
#include "pwm.h"
#include "delay.h"
#include "usart.h"
#include "touch.h"
#include "key.h"
int main(void)
{
double sinf1=6.58,sinf2=6.58,sinv1=1.52,sinv2=1.52,pwmf1=5.00,pwmf2=5.00,pwmr1=50,pwmr2=50;
u8 choice1=0,choice2=0;
u32 position=0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//设置系统中断优先级分组2
delay_init(168); //初始化延时函数
uart_init(115200); //初始化串口波特率为115200
LCD_Init();
LCD_BackInit(); //LCD初始化
KEY_Init();
tp_dev.init(); //触摸屏初始化
sin_Generation1(0.5);
sin_Generation2(0.5,0);
GPIO_Configuration();
TIM6_Configuration();
TIM7_Configuration();
DAC_DMA_Configuration1();
DAC_DMA_Configuration2();
TIM14_PWM_Init(200-1,84-1,100); //84
TIM10_PWM_Init(200-1,168-1,100); //168MHz
while(1)
{
if(IfTouch(25,25,200,200))//1 PA4
{
choice1=1;
RedDot(1);
POINT_COLOR=BLUE;
LCD_ShowDouble(280,50,sinf1,1);
LCD_ShowDouble(300,50+88,sinv1,2);
TIM_Cmd(TIM14, DISABLE);
DAC_DMACmd(DAC_Channel_1, ENABLE);
}
if(IfTouch(25,25+175,200,200+175))//2 PF9
{
choice1=2;
RedDot(2);
POINT_COLOR=BLUE;
LCD_ShowDouble(280,50+175,pwmf1,1);
LCD_ShowDouble(325,50+88+175,pwmr1,3);
DAC_DMACmd(DAC_Channel_1, DISABLE);
TIM_Cmd(TIM14, ENABLE); //使能TIM14
}
if(IfTouch(25,25+400,200,200+400))//3 PA5
{
choice2=1;
RedDot(3);
POINT_COLOR=BLUE;
LCD_ShowDouble(280,50+400,sinf2,1);
LCD_ShowDouble(300,50+88+400,sinv2,2);
TIM_Cmd(TIM10, DISABLE);
DAC_DMACmd(DAC_Channel_2, ENABLE);
}
if(IfTouch(25,25+175+400,200,200+400+175))//4 PF6
{
choice2=2;
RedDot(4);
POINT_COLOR=BLUE;
LCD_ShowDouble(280,50+175+400,pwmf2,1);
LCD_ShowDouble(325,50+88+175+400,pwmr2,3);
DAC_DMACmd(DAC_Channel_2, DISABLE);
TIM_Cmd(TIM10, ENABLE); //使能TIM10
}
if(choice1==1)
{
while(IfTouch(259-44,47,259,47+44)||IfTouch(396,47,396+44,47+44))
{
if(IfTouch(259-44,47,259,47+44))
{
if(sinf1<=1)break;
sinf1-=0.01;
}
if(IfTouch(396,47,396+44,47+44))
{
if(sinf1>=10)break;
sinf1+=0.01;
}
delay_ms(20);
TIM_Cmd(TIM6, DISABLE);
TIM_SetAutoreload(TIM6, (u32)(328.125/sinf1)-1);
TIM_Cmd(TIM6, ENABLE);
LCD_ShowDouble(280,50,sinf1,1);
}
while(IfTouch(259-44,47+88,259,47+44+88)||IfTouch(396,47+88,396+44,47+44+88))
{
if(IfTouch(259-44,47+88,259,47+44+88))
{
if(sinv1<=0.1)break;
sinv1-=0.01;
}
if(IfTouch(396,47+88,396+44,47+44+88))
{
if(sinv1>=3.3)break;
sinv1+=0.01;
}
delay_ms(20);
DMA_Cmd(DMA1_Stream5, DISABLE);
sin_Generation1(sinv1/3.3);
DMA_Cmd(DMA1_Stream5, ENABLE);
LCD_ShowDouble(300,50+88,sinv1,2);
}
}else if(choice1==2)
{
while(IfTouch(259-44,47+175,259,47+44+175)||IfTouch(396,47+175,396+44,47+44+175))
{
if(IfTouch(259-44,47+175,259,47+44+175))
{
if(pwmf1<=1)break;
pwmf1-=0.01;
}
if(IfTouch(396,47+175,396+44,47+44+175))
{
if(pwmf1>=10)break;
pwmf1+=0.01;
}
delay_ms(20);
TIM_Cmd(TIM14, DISABLE);
TIM_SetAutoreload(TIM14,1000/pwmf1-1);
TIM_SetCompare1(TIM14,(u32)(10*pwmr1/pwmf1));
TIM_Cmd(TIM14, ENABLE);
LCD_ShowDouble(280,50+175,pwmf1,1);
}
while(IfTouch(259-44,47+88+175,259,47+44+88+175)||IfTouch(396,47+88+175,396+44,47+44+88+175))
{
if(IfTouch(396,47+88+175,396+44,47+44+88+175))
{
if(pwmr1<=10)break;
pwmr1-=1;
}
if(IfTouch(259-44,47+88+175,259,47+44+88+175))
{
if(pwmr1>=90)break;
pwmr1+=1;
}
delay_ms(20);
TIM_Cmd(TIM14, DISABLE);
TIM_SetCompare1(TIM14,(u32)(10*pwmr1/pwmf1));
TIM_Cmd(TIM14, ENABLE);
LCD_ShowDouble(325,50+88+175,100-pwmr1,3);
}
}
if(choice2==1)
{
while(IfTouch(259-44,47+400,259,47+44+400)||IfTouch(396,47+400,396+44,47+44+400))
{
if(IfTouch(259-44,47+400,259,47+44+400))
{
if(sinf2<=1)break;
sinf2-=0.01;
}
if(IfTouch(396,47+400,396+44,47+44+400))
{
if(sinf2>=10)break;
sinf2+=0.01;
}
delay_ms(20);
TIM_Cmd(TIM7, DISABLE);
TIM_SetAutoreload(TIM6, (u32)(328.125/sinf2)-1);
TIM_Cmd(TIM7, ENABLE);
LCD_ShowDouble(280,50+400,sinf2,1);
}
while(IfTouch(259-44,47+88+400,259,47+44+88+400)||IfTouch(396,47+88+400,396+44,47+44+88+400))
{
if(IfTouch(259-44,47+88+400,259,47+44+88+400))
{
if(sinv2<=0.1)break;
sinv2-=0.01;
}
if(IfTouch(396,47+88+400,396+44,47+44+88+400))
{
if(sinv2>=3.3)break;
sinv2+=0.01;
}
delay_ms(20);
DMA_Cmd(DMA1_Stream6, DISABLE);
sin_Generation2(sinv2/3.3,position);
DMA_Cmd(DMA1_Stream6, ENABLE);
LCD_ShowDouble(300,50+88+400,sinv2,2);
}
}else if(choice2==2)
{
while(IfTouch(259-44,47+175+400,259,47+44+175+400)||IfTouch(396,47+175+400,396+44,47+44+175+400))
{
if(IfTouch(259-44,47+175+400,259,47+44+175+400))
{
if(pwmf2<=1)break;
pwmf2-=0.01;
}
if(IfTouch(396,47+175+400,396+44,47+44+175+400))
{
if(pwmf2>=10)break;
pwmf2+=0.01;
}
delay_ms(20);
TIM_Cmd(TIM10, DISABLE);
TIM_SetAutoreload(TIM10,1000/pwmf2-1);
TIM_SetCompare1(TIM10,(u32)(10*pwmr2/pwmf2));
TIM_Cmd(TIM10, ENABLE);
LCD_ShowDouble(280,50+175+400,pwmf2,1);
}
while(IfTouch(259-44,47+88+175+400,259,47+44+88+175+400)||IfTouch(396,47+88+175+400,396+44,47+44+88+175+400))
{
if(IfTouch(396,47+88+175+400,396+44,47+44+88+175+400))
{
if(pwmr2<=10)break;
pwmr2-=1;
}
if(IfTouch(259-44,47+88+175+400,259,47+44+88+175+400))
{
if(pwmr2>=90)break;
pwmr2+=1;
}
delay_ms(20);
TIM_Cmd(TIM10, DISABLE);
TIM_SetCompare1(TIM10,(u32)(10*pwmr2/pwmf2));
TIM_Cmd(TIM10, ENABLE);
LCD_ShowDouble(325,50+88+175+400,100-pwmr2,3);
}
}
delay_ms(100);
if(KEY_Scan())
{
while(KEY_Scan()==1)
position++;
while(KEY_Scan()==3)
position--;
DMA_Cmd(DMA1_Stream6, DISABLE);
sin_Generation2(sinv2/3.3,position);
DMA_Cmd(DMA1_Stream6, ENABLE);
}
}
}
3.说明
本题出自 电子科技大学 2019/3 信通科协院队第一次训练题。