stm32 波形检测，绘制

stm32 波形检测，绘制

红叶合适落水

校赛第三部分

详见

这里就简单多了

波形检测见

关于判断波形的类型

FFT还没用过

但一定频率范围内有两种方法

方案一

检测一下采集到的波形数据，大于某个值的数有多少个，就可以判断出是什么波形

方案二

将数组内相邻的两个数相减，判断差值；

差值为0，方波

差值为定值，但不为0，三角波

差值不是定值，正弦波。

关于STM32单片机对数的计算

直接使用公式是没法返回正确的值的

解决方案

利用中间变量

u16 lo = 0;u16 lo2 = 0;len = len - 1;LCD_Fill(0, 120, 240, 220, GREEN);for(i = 0; i < len; i++) {lo = 20 * log10(arr[i]);lo2 = 20 * log10(arr[i + 1]);LCD_DrawLine(i * 230 / len, (100 - lo) * 2 + 80, (i + 1) * 230 / len, (100 - lo2) * 2  + 80);}

主函数

int main(void)
{		int pending = 0;u8 t=0;Init();while(1){if(pending == 1) {printf("nr%d",Get_Adc(ADC_Channel_0));if(Get_Adc(ADC_Channel_0) > 3700) {} else {for(n = 0; n < 70; n++) {ADC_ConvertedValue2[n] = Get_Adc_vpp(ADC_Channel_0);delay_ms(16);}pending = 4;draw2(ADC_ConvertedValue2, 70, 40);LCD_ShowxNum(100,200,pending,1,16,0);}}t=KEY_Scan(0);		//µÃµ½¼üÖµswitch(t){				 case KEY0_PRES:pending = 0;draw(ADC_ConvertedValue, 200, 40);adc_init();LCD_ShowxNum(100,200,pending,1,16,0);break;case KEY1_PRES:pending = 1;Adc_Init();	LCD_ShowxNum(100,200,pending,1,16,0);break;case WKUP_PRES:		pending = 2;draw(ADC_ConvertedValue, 200, 40);adc_init();LCD_ShowxNum(100,200,pending,1,16,0);break;default:delay_ms(1);} }
}void ADC(u16 vpp1) {vpp1=Get_Adc_vpp(ADC_Channel_0);temp=(float)vpp1*(3.3/4096);vpp1=temp;LCD_ShowxNum(156,150,vpp1,1,16,0);temp-=vpp1;temp*=1000;LCD_ShowxNum(172,150,temp,3,16,0X80);
}void Init(void)
{NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);uart_init(9600);delay_init();	KEY_Init();LCD_Init();Adc_Init();		 POINT_COLOR=BLUE;//ÉèÖÃ×ÖÌåΪÀ¶É«      LCD_ShowString(60,150,200,16,16,"ADC_CH1_VPP:0.000V");adc_init();LCD_DrawLine(0, 100, 230, 100);LCD_SSD_BackLightSet(1);
}
void draw(u16 arr[], int len, int height)
{int num = 0;len = len - 1;LCD_Fill(0, 0, 240, 100, GREEN);for(i = 0; i < len; i++) {num += (arr[i] > 621) ? 1 : 0;LCD_DrawLine(i * 230 / len, 100 - (arr[i] / height), (i + 1) * 230 / len, 100 -  (arr[i + 1] / height));}printf("nr%d",num);if(num < 130) {LCD_ShowString(10,0,200,16,16,"Square");} else if(num > 140 && num < 170) {LCD_ShowString(10,0,200,16,16,"SIN");} else if(num > 175) {LCD_ShowString(10,0,200,16,16,"Triangle");}}void draw2(u16 arr[], int len, int height)
{u16 lo = 0;u16 lo2 = 0;len = len - 1;LCD_Fill(0, 120, 240, 220, GREEN);for(i = 0; i < len; i++) {lo = 20 * log10(arr[i]);lo2 = 20 * log10(arr[i + 1]);LCD_DrawLine(i * 230 / len, (100 - lo) * 2 + 80, (i + 1) * 230 / len, (100 - lo2) * 2  + 80);}LCD_Fill(0, 220, 240, 320, GREEN);for(i = 0; i < len; i++) {LCD_DrawLine(i * 230 / len, 100 - (arr[i] / height) + 200, (i + 1) * 230 / len, 100 -  (arr[i + 1] / height) + 200);}LCD_ShowString(230,210,16,16,16,"5");LCD_ShowString(230,280,16,16,16,"0");LCD_ShowString(0,300,48,16,16,"100");LCD_ShowString(100,300,64,16,16,"2.9k");LCD_ShowString(200,300,64,16,16,"5khz");LCD_ShowString(220,130,48,16,16,"14");LCD_ShowString(230,180,48,16,16,"0");LCD_ShowString(205,195,48,16,16,"-17");LCD_ShowString(210,250,48,16,16,"(V)");
}void draw3(u16 arr[], int len, int height)
{len = len - 1;LCD_Fill(0, 0, 240, 100, GREEN);for(i = 0; i < len; i++) {LCD_DrawLine(i * 230 / len, 100 - (arr[i] / height), (i + 1) * 230 / len, 100 -  (arr[i + 1] / height));}}