AME 3623: Project 0

• All components of the project are due by Tuesday, February 16th at 5:00 pm.
• Discussion and collaboration within your assigned groups is fine.
• Discussion across groups may not be about the specifics of the solution (general programming/circuit issues with other groups are fine to discuss).

By the end of this project, each individual in the group will demonstrate:

• writing, compiling and downloading code to the Teensy,
• writing code that affects the state of the digital output ports, and
• writing code that reads the state of the digital input ports.

Component 1

Insert your microprocessor slowly into the breadboard:

• The USB connector should hang off the end of the breadboard.

• Remember to only hold the processor by its edges.

• When you push downward on the processor, do so only along the pins (ideally in the corners of the processor).

• Note that some of the newer breadboards are very resistant to having pins/wires inserted into the holes. If you are having difficulty inserting the processor, then:
  • Remove the processor
  • Use a single wire to poke into the holes that you plan to use for the processor. This will loosen up the connections.
  • Replace the processor

• When you are done, it will look like this:

  

Complete the circuit:

• Connect +3.3V power and ground to the power and ground buses on the breadboard.
  • Remember that the power and ground buses are separated into four unconnected regions (two regions along each horizontal line in the above figure).
  • Add short jumper wires between each horizontal pair of regions.
  • Add longer jumper wires to connect the horizontal power buses; do the same for the ground buses. This is best done on the end opposite to the Teensy.
  • Always try to use the shortest wires possible. However, minimize the amount of wire that is exposed.

• Connect at least four LEDs to different output pins on your Teensy. These pins must be on the same Teensy port. Each of these LEDs needs to be connected to ground through their own 200 ohm resistor.

• Connect another Teensy pin on the same port to +3.3V through a 10K-ohm pull-up resistor. Connect this same processor pin to one of the side pins of a switch. Connect the common (middle) switch pin to ground.

Component 2

1. Waits for the switch to be pressed, then
2. Displays an interesting LED flashing pattern. The flashing pattern of each group member must be different.
3. Once the switch is released, the LEDs must turn off.
4. Repeat when the switch is pressed again

Notes

• Do not use Finite State Machines for this project (we will work on this next)
• Use setup() to initialize your pins/ports
• Use loop() to implement the switch checking and the LED flashing
• You must use the following coding pattern when turning LEDs on/off:

  GPIOx_PDOR = (GPIOx_PDOR & ~mask) | new_pattern;

  where:

  • mask is the bit pattern for all of your LEDs
  • new_pattern is the bit pattern for the LEDs that need to be in an ON state

What to Hand In

• Code: Check your documented code into the project0 area of Gradescope.

  Remember that documentation is about helping you and others looking at your code to understand what it is doing. Therefore, it will generally describe the logic of the code (and not-necessarily the low-level details). For this class:

  1. At the top of your C file, provide project-level documentation: include the project number, group number, group members, date and the group member responsible for the code.

  2. Each function must be documented (above the function header). This documentation must include:
     • A description of what the function does at a logical level,
     • A list of the input parameters and what their meanings are,
     • A description of the return variable type and meaning, and
     • If the function has external effects (e.g., commanding an actuator or modifying a global variable), these must also be documented here.
     NOTE: for project 0, no function-level documentation is required.

  3. In-line comments must be used to describe logically what is happening at that line or group of lines.

  See an example for the specific format that we are looking for.

Demonstration/Code Review

• The review triggers the grading process.

• The review must be completed by the Friday following the deadline. However, the sooner you have feedback, the better prepared you will be for the next project.

• The code and circuit must not have changed since the deadline (unless your group is taking a time penalty).

• All group members must be present.

• If a code review is completed before the deadline, you have the option to resubmit for an improved grade, as long as the submission is done before the deadline. Note that the resubmission may require a new code review.

Grading

For the first few projects, points will largely be assigned by the teaching staff, with an explanation for any points that are taken off of the full score. By the end of the semester, individuals / groups will assign their own score and justify their choices. These scores and justifications will be reviewed (and perhaps adjusted) during the code review process.

For this project, we expect:

• A properly configured circuit
  • Microprocessor installed
  • LEDs wired to the microprocessor (all to the same PORT)
  • Switch wired to the microprocessor (to the same PORT as the LEDs)

• Properly written software
  • Interesting LED flashing pattern
  • Flashing pattern is conditioned on the switch being pressed
  • The LEDs are controlled using the PDOR template that we have described in class and in the above specification

• Properly documented code
  • Project-level documentation at the top of the ino file: name and group number, date and project number
  • In-line documentation inside of functions: individual lines or small groups of lines have an English description that describes logically what the code is doing

References

• Teensy HowTo

andrewhfagg -- gmail.com

Last modified: Thu Feb 18 00:35:42 2021