ELEC 327: Digital Systems Laboratory (Spring 2023) Bonus Projects

Bonus projects should be submitted via email, and critically, with a Piazza post containing a YouTube video demostrating the projet. This way your fellow classmates will see what bonus projects are being done.

Accelerometer and LED circle board

The EAGLE CAD design files are found in the Bonus/ directory of the ELEC327 github repository. Here is a link to the schematic and one to the board. Note that the accelerometer is mis-wired - the MISO and MOSI wires are reversed. You can fix this by cutting these traces and soldering on airwires.

1. [1 point for whoever is first] - Make all 24 lights light up. Create a youtube video and post to campus. The first timestamped video will be worth 1 bonus point. (Note that there may be a problem with the PCB!)

2. [1 - 2 points] - implement a clock. The aesthetics of the clock and code will determine total scorer. Example questions: is there a second hand that ticks? a separate hour and minute hand? is there some sort of PWM-like intensity modulation? does the device calibrate and use the VLO for low power?

3. [3 point] - create a proof-of-concept accelerometer device (requiring the hardware airwire fix described above). Get data from the accelerometer and display it somehow with the LEDs. (Alternatively, an extra point will be applied for the following bonuses…)

4. [2 points] - implement a tilt sensor in which the LED closest and furthest from the ground light up. The button should be used to make the device sleep/wake up. This will require that you (a) properly solder the MSP430 and 3 shift register chips to drive the LEDs and (b) interface with the accelerometer to read out the gravity vector, and (c) appropriately compute its direction.

5. [up to 2 points] - derive optimized integer routines for (1) so that the update speed can be fast. Obviously, this also requires doing (1).

6. [up to 5 points] - do something cool that links motion to the LEDs.

Lab 1 Bonus - Color cyle Morse Code

[0.25 points] - Make sure that your implementation of Lab1 (Lab2 in 2021) morse code blinking project is using one of the Timer interrupts for character timing. Display the Morse code message on the RGB led of the Launchpad. Using a different timer interrupt, configure the color of the RGB LED to cycle through the rainbow (at least 16 different colors) while the message is being flashed. The color cycling should be faster than the character timing.

Lab 1 Bonus - Decode Morse Code

[2-6 points] - MVP (2 points): after implementing the Lab1 morse code blinking project, connect an input GPIO pin of a second MSP430 to the LED driving pin on the first one (you’ll presumably also need to connect the ground lines). Track the signal on this pin to infer dashes, dots, and spaces. Decode these to characters, which can be viewed in memory in the debugger. Extra points: (a) Implement a serial interface to see the translated characters. (b) Figure out how to synchronize the clock over a large range of frequencies. You can assume that the message is limited to 3-4 letters and repeats for a long time. (c) Use a photodiode or other light sensor to get the signal rather than a wire.

Lab 3 Bonus - Create a large digital clock or other fun things with the handout PCB

[1 point] - Implement a 2 digit stopwatch. With the display PCB oriented horizontally, implement a 2-digit display, and have it count hundredths of seconds. Use the two buttons as a start/stop and reset. When the time is greater than 9.9 seconds, while running, the display should show only seconds. When stopped, it should scroll the full three-digit time.

[1-2 points] - Implement a multi-PCB clock. Use the header pins on the sides of the PCB to chain 2, 4 or 6 of the display PCBs together. Program them such that the rightmost one controls the timing of the rest of the PCBs in the chain. Come up with an interesting way to use one pair of buttons to control the full display, for example, to set the time, or to change the intensity.

[0.5-2 points] - Create some sort of interesting game involving the display and the buttons button. Optional: implement a long press to send the device into LPM4 (like turning off).

[0.25 points] - Demonstrate your soldering skill by removing the 7 330 ohm resistors that limit the LED current and replace them with smaller 100 ohm resistors to make the display brighter. (Note that they are 0402 size!)

Lab 4-5 Bonus - Make your own PCB and related ideas

Note that all of these are PCB-related bonuses. You can create a second PCB for Lab 4 or submit these designs as part of the midterm or final project board runs. Alternatively, you could have them manufactured yourself. Some of the bonuses are obviously exclusive (i.e., one PCB couldn’t do everything); the rest should be considered additive (if you make one PCB that satisfies multiple bonuses, you get them all.)

[0.5 points] - Design and manufacture a PCB that includes nice features in silkscreen and/or soldermask layers.

[1 point] - Use the 32-pin QFN package of the MSP430 rather than the 20 pin one provided. You will have to find or create a proper EAGLE part for this device, which you should add to the ELEC327 library and generate a pull-request on github. Manufacture, populate, and program the board.

[1 point] - Add a button (or capacitive touch pad!) to the Lab 4 device to be used to go into LPM4 as in Lab 2. You may use a capacitor (and resistor if desired) to debounce, or implement some sort of software debouncing.

[1-3 points] - Add the necessary components to use this thermistor to measure the temperature of a liquid. Note that you’ll want to make a resistor divider circuit, with your ADC sampling the midpoint of the thermistor and a second resistor whos value you should choose intelligently. Turn your thermodot into a drink temperature alarm, possibly integrated into a cup. (For example, if the liquid is too hot to drink, display a red color and flash.) A useful device would probably also have a power button as described above.

Midterm Bonus - Better Simon

[0.25 - 0.5 points] - Make nice Youtube video showing your Simon game in action. Make sure that “Rice” and “ELEC327” are in the tile or otherwise searchable. Your demo video should show you playing through to a win, running the “Game Over - Win” animation, and then pushing a button to restart and then playing through but making a mistake to generate the “Game Over - Loss” animation. More points will be given for higher production quality, humor, or other aesthetics.

[0.5 - 1 point each] - Possible improvements or modifications for Simon:

• Implement software debouncing. (This requires removing the capacitors. Please reach out ASAP if you want a Simon board without capacitors and I will mail it.)
• Allow the user to select the level of difficulty - the timeout period and/or speed of initial sequence playing. You could implement this by which button is used to start the game after a reset.
• Implement the reset functionality by requiring multiple buttons to be pressed simultaneously
• Add double or triple button presses to the pattern
• Do something interesting with the LEDs (i.e., using the color channels creatively or specifying interesting patterns)
• Track fastest performance (i.e., how fast the entire game goes) and reward the player for beating their previous best
• Use the PCB for something else in addition to Simon (e.g., a different game, a music sequencer) that is executed depending on some startup condtion.