> For the complete documentation index, see [llms.txt](https://docs.aic-eec.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.aic-eec.com/embedded-systems/resources/basic-hardware-and-firmware/lab1-oscilloscope/waveform/lab-pulse-width-modulation-pwm/homework.md).

# Homework

จงออกแบบ [Metronome](https://www.google.com/search?q=metronome\&rlz=1C1CHBF_enTH783TH783\&oq=Metron\&aqs=chrome.1.69i57j69i59.9118j0j1&{google:bookmarkBarPinned}sourceid=chrome&{google:instantExtendedEnabledParameter}{google:omniboxStartMarginParameter}ie=UTF-8) ที่สามารถปรับค่า BPM ได้ตั้งแต่ 40 -100 BPM โดยใช้สัญญาณ clock ที่ความถี่ 100 Hz

-hint code-

```
const int input = 12; // This is where the input is fed.
int pulse = 0; // Variable for saving pulses count.
int var = 0;

void setup(){
  pinMode(input, INPUT);
 
  Serial.begin(9600);
}

void loop(){ 
  if(digitalRead(input) > var)
  {
    var = 1;
    pulse++;   
    Serial.println(pulse);
    //Serial.print(F(" pulse"));

    // Put an "s" if the amount of pulses is greater than 1.
    if(pulse > 1) {Serial.print(F("s"));}
   
   // Serial.println(F(" detected."));
  }
 
  if(digitalRead(input) == 0) {var = 0;}
 
}
```