An ESP8266-based quizbowl buzzer system.

Downloading Code and Setting up Environment

An important note: I developed this on a Windows machine using WSL. I have no reason to believe that this code won't work across platforms, but your mileage may vary.

You first need to download VSCode and get the PlatformIO extension.

VSCode can be downloaded from here, while the PlatformIO instructions can be found here. The quick start guide will give you an idea of the basic functionality of the extension.

You will also need the C/C++ Extension Pack (Can search and install with extension manager )

Once the above development tools are installed, open up a terminal and download the repository with the command

git clone https://github.com/mshettyFE/OpenBuzzer.git

NOTE: for Windows with WSL, you need to open up a WSL terminal instead of a typical powershell windows terminal.

cd into downloaded repository, then fire up VSCode with code . and click on the PlatformIO icon on the left hand taskbar. Choose the "Pick a Folder" option and select the root folder of the git repo you just downloaded. Wait for all the configurations to get setup.

Uploading Code to Units

In general, you need to do the following steps:

1. Copy over a .cpp file in the scripts directory into main.cpp.
2. Plug in the ESP8266 NODEMCU dev board to a USB port
   • Aside: If you are using WSL, you need to passthrough the USB connection from Windows to WSL. See here for instructions on how to do so.
3. Navigate to the PlatformIO icon in the taskbar, then select "Upload". It should just work.

For client machines (ie. each individual buzzer), copy over Client.cpp to main.

Uploading filesystem (Server only)

For the main control unit (ie. server), you also need to flash the filesystem image prior to uploading the code. Follow steps 1-2 above, then under the PlatformIO tab, select Build Filesystem Image. Afterwards, select Upload Filesystem Image.

Once that is done, you can copy over Server.cpp to main and upload like normal.

Ordering PCBs

The gerber files needed to create the PCBs are located at here. These specific design files work for JLCPCB. Just drag and drop the zip files and order however many you want (Suggested is 5 Server boards and 15 client boards).

If you are ordering from a different manufacturer, or some of your component footprints are egregiously misaligned with the board (the NODEMCU form factor and RJ45 PCB mounts are not particularly well standardized), you can directly modify the design files located here.

A suggestion to see if the current design works for you PRIOR to ordering from a fabricating service: print out the PCB layout on printer paper and see if your components roughly line up. It's OK if the pins don't line up exactly, since they can be slightly bent with pliers to correctly mate with the drill holes.

Assembly Tips

• Keep the soldering iron as low as feasible (Try not to go above 350 F). Lower heat means you are less likely to damage components and your tip
• Remember to properly clean the iron before and after use, and re-tin whenever you aren't using the iron
• Be careful not to smear solder onto the PCB traces while soldering. Pain to clean up
• The top left corner of the PCB (ie corner near OLED display) should align with the little divet on the bottom part of the enclosure
• OLED contacts go into indentation in OLED holder
• You can get away with 3 screws to secure the OLED, the PCB, and the cover
• Make sure that there are no shorts between wires prior to hot gluing them in place (pain to remove)