After spending some time watching the tutorial for Fusion, I was recommended to switch to KiCad as it would be more widely used by students, which could translate to more support. With the help of the aforementioned KiCad tutorial, I replicated the ATTiny412 pcb found on the website.

I initially wanted to create a design using the ESP32 S3, as I was told this would be ideal for my final project. However, this proved to be difficult and I wasn’t able to make sense of any preexisting designs in way that would help me to get closer to my final project.

Here are the following steps I took to create a PCB (as described in the tutorial):

• Download KiCad
• Clone KiCad library gitlab repo: https://gitlab.fabcloud.org/pub/libraries/electronics/kicad
• Open KiCad and upload footprints and designs
• Create a new schematic and select components
• In the schematic editor:
  • Double click each component and turn on foot print
  • Add nets and “net labels” that correspond to the pinout diagram the microcontroller
• In the PCB editor:
  • “Update PCB from schematic”
  • Adjust settings in “board setup”
  • Select track width and add routes
  • Add shape of PCB in the “edge cuts” layer
  • Arrange PCB components
  • Use “design rules checker” to make sure there are no errors with your board
  • “Plot” PCB using “gerber” as output directory
• Bring files into Gerber2Img and render

Simulating with Wokwi: #

In order to simulate a microcontroller with Wokwi, I used the most similar microcontroller I could find to the one that I modeled in KiCad, which ended up being the ATTiny85. For this simulation, I used a LED and resistor, and ran a simple code to make the LED blink:

#define LED_PIN 1

void setup() { pinMode(LED_PIN,OUTPUT); }

void loop() { digitalWrite(LED_PIN,LOW); delay(500); digitalWrite(LED_PIN,HIGH); delay(500); }

For this weeks group assignment, I tagged along with some friends from a different section and we spent a few hours toying with the different different electronics equipment.

Multimeter:

• shows amps, ohms and volts
• plug the black cord into the middle port
• plug the red cord into the left or right side based on the amount of amps you are using
• the sound icon allows you to tell if two things are connected
• positive side of diode (anode) goes to red cable of multimeter
• you cant have any power in your device when you are testing for resistance

Select the dial based on how much current or voltage is flowing through your device

how to measure current:

• this involves being in series with the load vs being in parallel
• you need to interrupt the system so that you become part of it
• it is more difficult to measure when you have a working PCB because you need to break the circuit somewhere

Why would you measure current?

• to troubleshoot if your drawing too much current
• you do this more so with power electronics

In series:

• there is a voltage drops
• same current, different voltage

In parallel:

• there is the same amount of voltage
• same voltage, different current (assuming the components are different)

Assemble electronics and measure

• red should be positive and black should be negative –> flat is associated with positive

High logic:

• connects to power

Transistor is a switch that the MCU turns on or off with power

• 0 doesnt let anything through
• 1 allows power through 0 is no voltage, 1 is

Low logic:

• connects to ground to turn on - digital low

Oscilloscope:

• plots voltage across time
• has a probe with two hooks that attach to the positive and negative side of the circuit

3.3 v is standard logic level

P = IV

Digital Logic Analyzer: TBD

Baud rate - determines how many ones and zeros are being sent per period per second

Resistor –> disappates power through the form of heat - a resistor can be placed before or after an LED in order to reduce the - power has to be zero at ground in order for an LED to work

Class Notes: #

Capacitor stores charge –> they serve as filters or ways to store charge Supercapacitors –> provide easily charged power

Inductors –> opposite of capacitors; they want steady current and will block changing current

Anode/Cathode –> Diode –> make currents go in one direction

Transistors: controls or amplifies current

• job is to have a low RDS
• logic level transitor turns on at low voltage

Mosfet –> N and P

• gate, drain and source
• help you to control power

Regulators:

• lowers voltage but not efficient

Op-amp

• you will set the parameters for this within the processor

Recitation Notes: #

Chip pin numbering is different than Arduino pin numbering Board Setup > Milling –> use 0.4 mm for cleanrance Gerber2img

Office Hours Notes: #

Regulator:

• voltage regulation

Capacitor:

• device used to create stability for power
• some times they are required to use

Resistor:

• acts as a limit for an LED so they don’t short circuit
  • you don’t need a resistor for an LED if you’re using a current power source
• an infinitely resistor is an open circuit
• an infinitely small resistor creates an infinitely large current
• a resistor is there to produce a different

Voltage

• you can only talk about the differential between two points
• voltage always needs two points

Vab = R * Iab

Inverse of resistance is conductance –> 1/r

Short circuit –> all current, no voltage Open circuit –> all voltage, no current

When circuit is in series, sum the voltage When circuit is parallel, sum the current

Resistors in parallel decreases resistance, and putting them in series adds resistance –> Kirchoff’s Law