對于下面這個程序我還有點不明覺厲 希望大佬能解釋一下
#include <Adafruit_SSD1306.h>
#define OLED_Address 0x3C
Adafruit_SSD1306 oled(1);
int x=0;
int lastx=0;
int lasty=0;
int LastTime=0;
bool BPMTiming=false;
bool BeatComplete=false;
int BPM=0;
#define UpperThreshold 550
#define LowerThreshold 500
void setup() {
oled.begin(SSD1306_SWITCHCAPVCC, OLED_Address);
oled.clearDisplay();
oled.setTextSize(2);
}
void loop()
{
if(x>127)
{
oled.clearDisplay();
x=0;
lastx=x;
}
int value=analogRead(0);
oled.setTextColor(WHITE);
int y=20-(value/45);
oled.writeLine(lastx,lasty,x,y,WHITE);
lasty=y;
lastx=x;
// calc bpm
if(value>UpperThreshold)
{
if(BeatComplete)
{
BPM=millis()-LastTime;
BPM=int(60/(float(BPM)/1000));
BPMTiming=false;
BeatComplete=false;
}
if(BPMTiming==false)
{
LastTime=millis();
BPMTiming=true;
}
}
if((value<LowerThreshold)&(BPMTiming))
BeatComplete=true;
// display bpm
oled.writeFillRect(0,19,128,20,BLACK);
oled.setCursor(0,19);
oled.print(BPM);
oled.print(" BPM");
oled.display();
x++;
}
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