6. Electronics Design

Group Assignment

• Use the test equipment in your lab to observe the operation of a microcontroller circuit board (as a minimum, you should demonstrate the use of a multimeter and oscilloscope)
• Document your work on the group work page and reflect what you learned on your individual page

Member	Role
Jenna, Tyler, Wilson	Documentation
Jenna	Multimeter Test
Tyler and Jenna	Oscilloscope Test
Wilson	Logic Analyzer Test

Multimeter Test

I used the multimeter to measure voltage in a differently programmed LED. I referenced Landon, David, and Ryan’s documentation from last year for the PWM to change the brightness.

Breadbord

I wired a breadboard with the microcontroller and an LED, then plugged it in.

Oscilloscope Test

Ms. Horstman walked us through the math of voltage, frequency, and wavelength. We learned that oscilloscopes display a graph. The vertical axis is voltage and the horizontal axis is time. We tested the same constant voltage and brightness change script.

For constant voltage, the LED was substantially dimmer. As indicated by the height of the voltage line on the oscilloscope, though, it works properly.

Constant Voltage Code

I decided to use a XIAO RP2040 and coded the LED to remain on.

void setup() {
  Serial.begin(115200);
  pinMode(26, OUTPUT);
}

void loop() {
   analogWrite(26, HIGH);
}
 ```

### Constant Voltage Video
<div style="padding:177.78% 0 0 0;position:relative;"><iframe src="../images/week6JTW/Jenna/Img0691.mp4" frameborder="0" allow="autoplay; fullscreen; picture-in-picture; clipboard-write; encrypted-media" style="position:absolute;top:0;left:0;width:100%;height:100%;" title="S"></iframe></div><script src="https://player.vimeo.com/api/player.js"></script>

### Brightness Change Code
I then programmed the LED to fluctuate in brightness. I did so using analogWrite, and since my pin is already PWM, I just changed the programming. The brightness for analogWrite ranges from 0-255 and the counter increases the brightness by intervals of 5.

```C++
void setup() {
  Serial.begin(115200);
  pinMode(26, OUTPUT);
}

void loop() {
  for (int i = 0; i <= 255; i+=5) {
    analogWrite(26, i);
    delay(50);  
  }

  for (int i = 255; i >= 0; i-=5) {
    analogWrite(26, i);  
    delay(50);  
  }                    
}

Brightness Change Video

Logic Analyzer Test

For the Logic Analyzer, we first used the Analog Discovery 2.

We then plugged in the wires to our LED circuit to the Analog Discovery 2 according to the instructions on Dariyah Strachan, Dylan Ferro, Ginny Foster, Stuart Christhilf, and David’s Documentation.

Then, I went into Waveforms, which is a software used for signal analysis, oscilloscope, logic analysis, and waveform generation with devices like the Analog Discovery and Digital Discovery. When connecting, we made sure to connect the power to the attiny’s power pinout and the ground connected to the ground of the analog discovery.

We clicked run, and this is what we got.

Files

Constant Voltage Code
Brightness Change Code>

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Last update: April 2, 2025