What did you personally accomplish this week on the project? Give files or photos that demonstrate your progress. Prove to the reader that you put sufficient effort into the project over the course of the week (12+ hours).
- I also re-flashed all the Picos with the new code which includes error handling in cases where the received word does not include valid alphanumeric characters. It turns out that when an invalid string to be parsed is sent to the Pico, an exception is thrown and the Pico is unable to continue even if the right data is sent to this. Hence this requires us to turn on/off the Pico. With this modification, all the Picos can function with multiple repeat games without having to be turned off.
- I verified the functionality of all the connections of each pogo pin on the grid and had to replace some of the jumper cables on the grid that were not producing electrical connections. One of the Picos also had a malfunctioning UART pin so we had to resolder that as well. This helps to ensure that any errors that could arise is due to the perf board itself instead of the grid.
- I completed the soldering of the perf board PCB and integrated it with the 16 block test bed on Monday. There were a lot of issues encountered when soldering the perf board especially with weak connection for some of the pins, causing bad data to be transmitted or the blocks to not ACK all the time. I also encountered a strange error where block positions 0 and 2, and 1 and 3 will get uploaded at the same time. After repeated debugging, to figure out if it was the blocks, pogo pins or the perf board circuitry that was the issue, I found out that it was due to a malfunctioning GPIO pin in the RPi that was controlling the mux, causing there to be some lag when selecting the UART lines. After switching out the MUX select pins, I was able to implement successful uploading of words to all 16 blocks. (Refer to test video)
- After Alexis laser cut the plywood for the grid, I helped with testing the electrical connections and debugging the circuitry to ensure that it all still worked with the actual grid instead of the test bed.
- I also worked on the latency testing but modifying the embedded controller code to be able to specify the duration of latency delay to allow us to vary it for testing purposes.
Is your progress on schedule or behind? If you are behind, what actions will be taken to catch up to the project schedule?
My progress is on schedule. I plan to work on getting all the quantitative results for latency testing over the weekend in time for the final presentation.
What deliverables do you hope to complete in the next week?
In the next week, I hope to implement some extensions and aesthetic improvements to the project. I wish to ensure that the colors of the LCD on the Picos are visible. I also hope to try out multithreading to allow multiple words to be uploaded to different blocks concurrently, speeding up the process of the uploading phase.
As you’ve designed, implemented and debugged your project, what new tools or new knowledge did you find it necessary to learn to be able to accomplish these tasks? What learning strategies did you use to acquire this new knowledge? We recognize that there are quite a few different methods (i.e. learning strategies) for gaining new knowledge — one doesn’t always need to take a class, or read a textbook to learn something new. Informal methods, such as watching an online video or reading a forum post are quite appropriate learning strategies for the acquisition of new knowledge.
I was working on the embedded controller portion of the code, including the Rpi and Pico. I had to find out how to control all the components via Python such as the Sparkfun LCD, detecting button press, UART communication with each block and the RGB Waveshare LCD.
I referred to online documentation about Sparkfun LCD for the LCD portion of the code. I also looked at Medium articles and watched online videos to figure out how to enable UART1 on the RPi. For the serial communication between the RPi and Pico, I looked into online forum posts for references on how to structure my code, potential suggestions for waiting for the serial transmissions and delays necessary to ensure that sufficient time was given for UART transmission. I also looked into online forum for error handling processes. I also searched up Arduino forum to figure out the button circuit to use for our submit buttons. For the button callback function, I looked into the Rpi HQ guide online for how to integrate the button into the RPi program without blocking the rest of the program flow.
I also had to debug the perf board after soldering it, hence I looked into the datasheet for the MUX to figure out which pins have to be connected to ensure the MUX is working well. I also looked into online forums to figure out possible ways that could prevent a block from ACK-ing, deriving the solutions of: poor connection between ground of Pico and UART and loose wires of TX/RX.