🔬 Lab
CS 240 Lab 1
Learning Goals & Reflection
CS 240 Lab 1
Learning Goals
Note: Each lab will have a learning goals page like this one. At the end of lab, you’ll be asked to fill out a Google form to reflect on your learning in each category.
Core Goals
Students can:
- Use basic electronic concepts:
- Memorize Ohm’s law and explain what current, voltage, and resistance are at a high level in terms of electricity.
- Explain the dangers of electric shock, and how current, voltage, and resistance contribute to electric danger/safety.
- Explain what a “short circuit” is and why is is usually undesirable.
- Explain the basic components necessary to form a “closed circuit” and what an “open circuit” is in contrast.
- Read circuit diagrams and truth tables:
- Recognize the circuit diagram symbols for resistors, transistors, voltage sources, and ground connections
- Explain how connected vs. disconnected crossing points are indicated in a circuit diagram.
- Explain what letter labels in a circuit diagram mean.
- Identify the output of a circuit for certain inputs based on a truth table.
- Analyze a circuit diagram piece-by-piece to figure out the voltage level and current availability at each point in the circuit, given known input voltages.
- Analyze the operation of a circuit for all possible input high/low voltage combinations to build a truth table for each output.
- Analyze the operation of a circuit abstracted over unknown input voltages to describe the overall operation of the circuit in terms of abstract inputs.
- Recognize the circuit diagram symbols for NOT, AND, and OR gates.
- Recognize the circuit diagram symbols for NAND and NOR gates.
- Build and explain basic transistor circuits:
- Identify voltage and ground sources and trace how these are connected on a protoboard.
- Explain how rails are connected horizontally and vertically inside a protoboard.
- Cut and strip plastic-shielded wire.
- Plug wires into a protoboard to make connections to components that are already mounted.
- Identify resistors, transistors, LEDs, and integrated circuits, both as physical components and on circuit diagrams.
- Explain how to connect to the push-button input, logic switch input, and logic indicator output sections of our prototyping stations.
- Explain what will happen if you create a transistor circuit without including any resistors.
- Wire a transistor with a push-button input to serve as a NOT gate controlling a logic indicator LED, given a diagram of the circuit.
- Wire two transistors in parallel to create a circuit which implements a NOR gate, given a diagram of the circuit.
- Explain how transistors can be used to create a circuit for a NOT gate, and the operation of the circuit in terms of where current flows and why in each possible input configuration.
- Work with integrated circuits:
- Read model numbers on integrated circuits and look up their wiring diagrams.
- Use the notch to identify the “top” of an IC, and “count around” the IC to identify each input/output pin on a physical IC based on a wiring diagram.
- Identify power and ground inputs from an IC’s wiring diagram and connect these to the +5V and ground lines on a prototyping station.
- Use a 7408 AND gate IC along with built-in switches and LEDs to create a circuit that requires two switches to be turned on at once in order to light up an LED.
- Test the outputs of a circuit built on a prototyping station to fill in a truth table for that circuit.
- Work with Boolean algebra notation:
- Explain how AND, OR, and NOT are represented in Boolean algebra notation.
- Explain the input/output relationships for a Boolean algebra function in plain language.
- Draw a circuit diagram involving basic gates to represent a Boolean algebra function, correctly labeling input and output wires.
Stretch goals
- Build and explain basic transistor circuits:
- Explain how transistors can be used to create a circuit for a NOR gate, and the operation of the circuit in terms of where current flows and why in each possible input configuration.
- Explain the difference (or lack thereof) between inputs and outputs in a circuit.
- For each basic gate (NOT, AND, OR, NAND, and NOR), explain how it can be constructed using transistors.
- Work with integrated circuits:
- Use 7408 AND gate and 7432 OR gate ICs along with built-in switches and LEDs to create a circuit that implements the Boolean function , where is a logic indicator output and , , and are logic switch inputs.
- Work with Boolean algebra notation:
- Write a Boolean algebra function which gives the output of a circuit show in a circuit diagram.
Reflection
Fill out the CS 240 Lab 1 Reflection form to complete today’s lab reflection.