assignments

Assignment

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

Individual Assignment:Use an EDA tool to design a development board to interact and communicate with an embedded microcontroller

All the important links are Here

Learning outcomes

Select and use software for circuit board design

Demonstrate workflows used in circuit board design

Group Assignment

For further information, please check our 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)

Multimeter

This is the multimeter we used

Here is a labelled image of it.

What is a Multimeter?

A multimeter, short for "multiple meter," is a versatile electronic instrument used to measure various electrical characteristics of electronic circuits and components. It typically combines several measurement functions into one device, allowing users to measure voltage, current, resistance, and often other parameters such as capacitance, continuity, and diode testing.

Here are some common functions and features of a multimeter:

Voltage Measurement: Multimeters can measure both DC (Direct Current) and AC (Alternating Current) voltage levels. They are used to measure the voltage across different points in a circuit.
Current Measurement: Multimeters can measure both DC and AC current. They can be used to measure the current flowing through a circuit or component.
Resistance Measurement: Multimeters can measure the resistance of resistors or other components in a circuit. This feature is useful for troubleshooting circuits and checking for faulty components.
Continuity Testing: Multimeters can check for continuity in a circuit, indicating whether there is a complete path for current flow. This is often used to check for broken wires or connections.

Oscillioscope

What is a Oscillioscope?

An oscilloscope is a tool used in electronics to visualize and measure electrical signals over time. It displays these signals on a screen as waveforms, allowing engineers and technicians to analyze various properties such as voltage, frequency, and timing. Oscilloscopes are essential for troubleshooting, design, and testing electronic circuit

Common functions and features of an oscilloscope include:

Channels: Most oscilloscopes have multiple input channels, allowing you to measure and display several signals simultaneously.

Vertical Controls: These controls adjust the voltage scale and position of the waveform on the screen for each channel.

Horizontal Controls: These controls adjust the time scale and position of the waveform on the screen, enabling you to analyze signal timing.

Waveform Display: The oscilloscope displays waveforms graphically on a screen, showing voltage on the vertical axis and time on the horizontal axis.

Measurement Functions: Oscilloscopes can measure various waveform parameters, including voltage, frequency, period, rise time, fall time, and more.

Automatic Measurements: Some oscilloscopes offer automatic measurement functions that calculate and display waveform parameters without manual intervention.

Individual Assignment

Use an EDA tool to design a development board to interact and communicate with an embedded microcontroller

Designing

To design the Schematic and PCB, I used the Kicad Software

I started my schematic with this as a reference, I created the sketch for my final project board. And also considering the basic circuit for the ATtiny44 I found in embedded programming page under the fab academy site.

Firstly, to get familiar with using the software. It is a must you know the tools availble.

Tools you need to keep in mind

Adding symbol library

Electronic Rule Checker(ERC)

It's a feature that automatically checks your schematic for common electrical errors or rule violations. When you run the ERC, KiCad analyzes your schematic to ensure that it adheres to certain electrical design rules and standards. ERC in KiCad acts like a spell checker for your schematic, helping you catch potential mistakes or problems that could cause issues in your circuit. It checks things like unconnected pins, duplicate net names, incorrect power connections, and other common errors to ensure your design is electrically sound. Running ERC before moving to PCB layout helps prevent costly mistakes and ensures a smoother design process.

Annotate

Annotation in KiCad refers to the process of assigning unique identifiers or reference designators to the components in your schematic. These identifiers help distinguish one component from another and are essential for the proper organization and assembly of your circuit.annotation in KiCad ensures that each component in your schematic has a distinct name or number so that they can be easily identified during the design process and when assembling the physical circuit board. This helps avoid confusion and ensures that all components are correctly placed and connected.

Go to "Tools" on the top tool panel, and click on "Annotate Schematic"

Adding footprints

Footprints in KiCad are like outlines or stamps that show where to place electronic components on a printed circuit board (PCB). They define the size, shape, and layout of pads and solder mask openings for soldering components onto the board.

Go to "Tools" and click on "Assign footprints"

Starting the schematic

At first I connected every symbol with wires and added a resistor for every switch I had.

Then I remembered that our instructor taught us about labels!

Then I switched to PCB editor

Now lets get to know the tools there!

Additing predefined netclass

Adding predefined net classes in the PCB editor in KiCad allows you to organize and manage groups of nets with similar properties, such as signals or power connections. This feature simplifies the routing process by applying specific design rules or settings to entire groups of nets at once.

While editing the pcb, I needed more 0 ohm resistors.

These are the versions of my board(I am very bad in making connections in PCB editor)

Then finally I was relieved but..

.....I ended up with 19 0ohm RESISTORS!!!

Printing

I will be using the Roland SRM 20

UH OH...

I set the origins wrong and not 0 while making the .rml file. And it resulted in the printer milling the wrong way and breaking a 1/64 drilling bit.

But our instructor gave us a new drilling bit! YIPPEY!!

Becuase I broke a drilling bit, Damzang helped me set the machine up and create the .rml file.

Printing(milled the right direction)

Routes

Edge cuts

Taking out!

Done!!

Soldering

Components

Programming

With the help of Yangtshel(My friend), I tried programming my board using AVR ISP. But the code never uploaded. And everytime we connected the GND of my board to the GND of the Arduino UNO it kept losing connection. I showed it to my Instructor and he helped me fix the problem. It turned out that the problem was with my 19 0ohm RESISTORS! So the main problem was caused when I added a 0 ohm resistor of which one side connected to VCC and the other to GND. And the reason why you can't connect a resistor between a VCC and GND is because(As explained by my friend Yangtshel to me) connecting VCC and GND directly with a 0 ohm resistor effectively creates a short circuit between the power supply's positive and ground terminals. This short circuit could potentially damage the power supply or other components in the circuit(The GND and VCC always have to be seperated)

That is why the below didn't work. I didn't remove the 0 ohm resistors that created a short circuit in my board.