Week of 2/24 - 2/28

This week I made lots of progress on the word clock. Last week we discovered that the LEDs on the light strip were arranged differently than the LEDs on the Word Clock board. This meant that I had to change the code for the letters that lit up on the Word Clock board and the elements in the arrays I created. Along with this, I realized we had to rearrange some of the blocks on the Word Clock board to make the code change more feasible for me. We only had to switch two words ("quarter" and "ten") to place them in the order that I wanted them in. After Kim and Bella did this, I went back to the LED map that I made in a Google Doc to have it correspond to the new arrangement of letters on the display. With the new LED map, I changed the elements in the array so that they corresponded to the correct letters and words on the display. After doing this, I tested all of the newly arranged elements on the word clock and found that they worked well and the correct letters would light up given the correct value.

New LED map; the letters follow a different ordering to light up than I had initially assumed when starting the project.

After doing this, I decided to start designing the PCB for the clock. I began with creating all of the elements for the Word Clock in a new library as I did not have the proper elements to create the PCB for this project in my old library. After I made the elements, I designed an initial prototype of the PCB. I still have to ensure that the PCB follows the DRC rules but my main goal with designing the PCB was to have something I could easily change in fusion if I need to because the clock's software still needs to be tweaked and changed. The PCB is simple but it has all of the things I need right now for the Word Clock (header for LEDs, RTC header, and Metromini header).

Lastly, I figured out a way to power the Word Clock from the top and the bottom of the board. To do this, I had to run a cord from the final LED on the Word Clock to the breadboard I am currently using so that the power can be drawn from both ends of the clock. Since the LEDs use lots of power and require a lot of power to light up all of them properly, with only one connection to power, the lights towards the bottom of the display are less bright and flicker very often because there isn't enough current flowing to the lights to turn them on. This is solved by a second cord that connects to power from the bottom of the display. To do this, I had to use one of the extension wires for the LEDs we were using and connect that to a longer jump wire to connect power and ground to the breadboard near the top. My solution temporarily was to crimp the ends of the extended wire so it could plug into the breadboard while attaching it to the other extension wire (the one connected directly to the LEDs) with wire nuts. This worked and the lights at the bottom lit up properly and no longer flicker. There is a chance that I have to add more wires for power that run down the middle of the board but I haven't determined if I have to do that quite yet. Right now I am shifting my focus to making sure I use an RTC that will consistently display the correct time as I discovered today that the time wasn't completely accurate on the display.

Working clock with the correct arrangement of letters and power from both ends.