Sports Board (LED 32×64 Matrix and Raspberry Pi)

I recently got motivated to do a project I have wanted to do for a while. One of my friends is an avid sports fan, so for Christmas I decided to make up a nice little gift for him. I have a few older Pi2s lying around so I figured why not try making the sports board.

The project itself is fairly straight forward and does not require a lot of parts.

1. Raspberry Pi (I am using a Pi2b for this, so I also needed an external Wifi adapter due to the lack of it being built into that particular model board.)
2. Latest 32 bit Raspberry Pi OS imaged onto a Micro SD card.
3. The LED matrix board. I used this off of Amazon. This is a 32×64 pixel P3 board. So it is 32 rows by 64 columns of LEDs spaced 3 mm apart.
4. 5VDC power supply (I used a 5 amp supply since I wanted to power the LED board and Pi with one power supply.

Attaching the LED board to the Pi was a fairly tedious task. Although there is only 16 pins in the harness that need to be attached to the GPIO pins of the Pi, it is always a pain to manually count the pins as they are not labeled.

As you can see in the picture above, I modified the power harness that came with the LED board. The power harness comes with two spade connectors on one end and then 2 – 4 pin plugs in parallel on the other end. This is to make it easier to power two LED boards at the same time. Since we are just going to be using one, I cut one of the plugs off of the harness with about 4″ of wire left on it. I then soldered the two black together and the two red together.

I then cut one end off of two extra GPIO jumpers that I had on hand. Connecting one to the black line and to a ground GPIO pin. I then connected the other jumper to a 5V GPIO on the Pi and to the the red line. Finally, I attached the 5VDC power supply to the corresponding lines.

After the initial hardware setup was done, I decided to test the hardware out with a demo prescribed in the surprisingly detailed two page manual that came with the LED board.

Before using Git to get retrieve the software, two things needed to be changed with the configuration of the Pi.

First, /boot/config.txt needs to be modified so “dtparam=audio=off” to turn off the on board audio. And also “1-wire interface” needs to be disabled using $sudo raspi-config .

Once those two items are are done it is okay to download

$ sudo git clone https://github.com/hzeller/rpi-led-matrix
$ cd rpi-led-matrix
$ sudo make
$ cd examples
$ sudo ./demo -D 9 --led-rows=32 --led-cols=64

You should then get a nice output of waves to the LED board that looks like this:

Alas, that did not actually work the first time for me… instead I got a nice error that looked like this:

Well isn’t that wonderful, I thought we already turned the sound off? Guess not. So I ran the command with the added option:

$ sudo ./demo -D 9 --led-rows=32 --led-cols=64 --led-no-hardware-pulse

And it worked! Great, except for some reason I felt like it was going to be a problem later on down the line. So I did a little visit to the discord group and found a solution for the issue (thank you mattcooker). A series of commands need to be ran to clear it up:

$ lsmod | $ lsmod | grep snd_bcm2835
# if this returns anything, then continue
$ cat <<EOF | sudo tee /etc/modprobe.d/blacklist-rgb-matrix.conf
> blacklist snd_bcm2835
> EOF
blacklist snd_bcm2835
$ sudo update-initramfs -u
$ sudo reboot now

With the reassurance that this will clear up any future issues, it was time to start with getting the “Sports Board” downloaded and installed. I am not going to go into detail about how to download and install this, as the documentation is fairly clear on the github page:

https://github.com/robbydyer/sports

Although, I will mention one hiccup I had. I got everything installed and working.. well should have been working… In fact I pounded my head on my desk for quite a while trying to figure out what was going on. All I could get for an output from the sports app was two solid green lines across the screen. Stop the app… run the demo and hey it works. Well finally I found my issue inside the configuration file.

$ sudo nano /etc/sportsmatrix.conf
---------
hardwareMapping: adafruit-hat
needed to be changed to:
hardwareMapping: regular
---------
$ sudo systemctl stop sportsmatrix
$ sudo systemctl restart sportsmatrix

When I flashed the Micro SD card, I named the Pi “sportsboard” so I can access the web interface @ sportsboard.local . There are many options to setup and different game options… I am not a die hard sports fan by any stretch, but man is this thing pretty cool.

I decided to print up a stand for it:

The bracket in the middle I had to design to mount the Pi 2 to so it sat in there nice and tight.

Finally, the last step was to make sure that the Pi would connect to my friends WiFi once he took to his house. The Pi was currently setup to connect to my WiFi, so I needed to add a second network for it to connect to.

$ sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

Which brings up the configuration file for the Wifi:

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

I then added under those two lines:

network={
    ssid="mainwifiname"
    psk="**********"
}

network={
    ssid="friendswifi"
    psk="**********"
}

Exit and save then a quick reboot verifying it connected to my network again and it was good to go! A fun little project complete.