A multi-function display by your bedside!

The 64x64 LED Matrix is a great platform to display anything you care about. Like the time and what day it is. :) With the motion and light sensor, the display can be made to dim or blank out so it will not disturb you while sleeping. A simple wave motion in the dark room is enough to re-enable the display for a short period.

The 3D printed harness file is available with this project, so you can adapt it to suit your bed or desk space needs.  In the current form, two printed parts are glued together with regular table pin connectors. You will also need four M3x5mm flat head screws in order to connect the matrix display to the printed frame.

The code is written in Python and has lots of potential for easy improvements. The current implementation gives you the ability to connect to an MQTT broker for subscribing and publishing events in a canonical IOT setup. But you need not to worry about that if a clock is all you care about. Underneath the Python code, this project uses the display driver written by Henner Zeller, which makes the display fast and stable when used together with the Adafruit parts.

Prerequisite Guides

I suggest walking through the following guides to get a better understanding of the electronics.

• Adafruit APDS9960 breakout Digital Proximity, Ambient Light
• RGB Matrix Bonnet for Raspberry Pi

Parts

Take a moment to review the components in the circuit diagram. This illustration is meant for referencing wired connections - the length of wire, position and size of components are not exact.

Note that in order to drive the 64x64 dot matrix display, you must connect GPIO pins 4 and 18.

RGB Matrix Bonnet connects to the Raspberry Pi Zero.

The 2.1mm Male DC adapter and will need to be 150mm long.

While it is okay to use a single power supply to feed both RPI and matrix display, it is important that the throughput is powerful enough.

5v 10A switching power supply is plenty for this project.

The OnShape online tool was used in order to design the structure used for the bedclock. It exports STL files that you can use for 3D printing.

More details will be provided on the assembly section, but here is a picture showing how the 3 main parts go together:

• Top bezel
• Front bezel
• Matrix display

First, make sure you've loaded the latest Raspbian Lite operating system on your Raspberry Pi.  You can find the OS image download here, instructions for burning to an SD card image here, and a convenient guide here that explains how to load an operating system.

Next, have your Raspberry Pi connected to the Internet, either with a wired connection to its ethernet port, or by setting up wireless access to a WiFi network.  Check out the guide on network setup for more details on using wireless and WiFi networks with the Pi.

Once your Raspberry Pi is powered up and connected to a network you can follow the steps below to install the bedclock software.

If you're familiar with connecting to the Raspberry Pi over SSH you can use an SSH terminal application to connect.  If you aren't familiar with SSH, you can use the Adafruit Pi Finder tool to find your Raspberry Pi and open a terminal to run the installation. In either way, you should be able to be logged into the RPI as user pi.

Customization Options

As part of the Raspbian installation, visit the various options available and see if any of them needs tweaking. Setting the timezone is a good candidate. :)

Enable I2C via raspi-config

In order to read the gesture sensor, I2C must be enabled via the raspi-config interface. Follow the guide below for a step by step guide. If your familiar with this, use sudo raspi-config and enable I2C through the “Interfacing Options.”

sudo raspi-config

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sudo raspi-config

• Localization Options -> change timezone
• Interfacing Options -> enable ssh
• Interfacing Options -> enable I2C

sudo apt-get install -y git i2c-tools \
  python3-dev python3-pillow python3-setuptools cython3

# Ensure i2c device is present
ls /dev/i2c*  && echo ok || echo bad error cannot see i2c

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sudo apt-get install -y git i2c-tools \
  python3-dev python3-pillow python3-setuptools cython3

# Ensure i2c device is present
ls /dev/i2c*  && echo ok || echo bad error cannot see i2c

Install Matrix Driver

OK, now you are ready to install the driver for the LED matrix. We have a script that downloads the code and any prerequisite software. It works with the current Raspbian “Stretch” operating system (either the Lite or Desktop version). Walk through the options it presents and select the ones that pertain to your setup. If you get stuck, we have a more details in the Bonnet Matrix guide.

curl https://raw.githubusercontent.com/adafruit/Raspberry-Pi-Installer-Scripts/master/rgb-matrix.sh >rgb-matrix.sh
sudo bash rgb-matrix.sh

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curl https://raw.githubusercontent.com/adafruit/Raspberry-Pi-Installer-Scripts/master/rgb-matrix.sh >rgb-matrix.sh
sudo bash rgb-matrix.sh

The script will confirm your selections and offer one more chance to cancel without changes.

There’s a lot of software to update, download and install, so it may take up to 15 minutes or so to complete. Afterward, you’ll be asked whether you want to reboot the system.

Testing the Matrix Code

After the reboot, it's time to try the display! Run the following command and make sure it is working properly. By the way, it is okay to do this after the whole assembly; just come back here once the display is properly powered and connected.

cd ~/rpi-rgb-led-matrix/examples-api-use

ROTATE=180
TIMEOUT='10s'
PARAMS='--led-rows=64 --led-cols=64 --led-brightness=88'
PARAMS+=' --led-gpio-mapping=adafruit-hat'
for X in 0 {3..11} ; do \
     sudo timeout ${TIMEOUT} \
          ./demo ${PARAMS} --led-pixel-mapper="Rotate:${ROTATE}" -D${X}
     sleep 0.3
done

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cd ~/rpi-rgb-led-matrix/examples-api-use

ROTATE=180
TIMEOUT='10s'
PARAMS='--led-rows=64 --led-cols=64 --led-brightness=88'
PARAMS+=' --led-gpio-mapping=adafruit-hat'
for X in 0 {3..11} ; do \
     sudo timeout ${TIMEOUT} \
          ./demo ${PARAMS} --led-pixel-mapper="Rotate:${ROTATE}" -D${X}
     sleep 0.3
done

Press Control+C to stop the program and get back to the command line.

Create a .pth file so Python always includes a path to rgbmatrix

The python bindings for rgbmatrix are needed, so the bedclock software can control the matrix display.

SITE_DIR="$(sudo python3 -c 'import site; print(site.getsitepackages()[0])')"

[ -n "$SITE_DIR" ] && \
  echo "/home/pi/rpi-rgb-led-matrix/bindings/python" | \
    sudo tee "${SITE_DIR}/rgbmatrix.pth" >/dev/null

sudo python3 -c 'import rgbmatrix; print("ok:", rgbmatrix)' || echo FAILED

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SITE_DIR="$(sudo python3 -c 'import site; print(site.getsitepackages()[0])')"

[ -n "$SITE_DIR" ] && \
  echo "/home/pi/rpi-rgb-led-matrix/bindings/python" | \
    sudo tee "${SITE_DIR}/rgbmatrix.pth" >/dev/null

sudo python3 -c 'import rgbmatrix; print("ok:", rgbmatrix)' || echo FAILED

Install Git, Pip and Clone

Let's get the git command so we can clone the bedclock software repository. We will also need some Python packages, which we can easily obtain by using the pip command

sudo apt-get install -y python3-pip git

BRANCH=adafruit
cd && \
git clone -b ${BRANCH} \
  https://github.com/flavio-fernandes/bedclock.git  bedclock.git

cd ~/bedclock.git && sudo -H pip3 install --break-system-packages --upgrade -r ./requirements.txt

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sudo apt-get install -y python3-pip git

BRANCH=adafruit
cd && \
git clone -b ${BRANCH} \
  https://github.com/flavio-fernandes/bedclock.git  bedclock.git

cd ~/bedclock.git && sudo -H pip3 install --break-system-packages --upgrade -r ./requirements.txt

Automatic Startup

We will use systemd to start the program automatically. This is just a copy command away from the cloned repo.

# add bedclock service to systemd
sudo cp -v ~/bedclock.git/bedclock/bin/bedclock.service \
  /lib/systemd/system/
sudo systemctl enable bedclock.service

# start the application
sudo systemctl start bedclock.service

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# add bedclock service to systemd
sudo cp -v ~/bedclock.git/bedclock/bin/bedclock.service \
  /lib/systemd/system/
sudo systemctl enable bedclock.service

# start the application
sudo systemctl start bedclock.service

You can monitor what is happening with the app by looking at the log or systemd status:

sudo systemctl status bedclock.service

sudo journalctl -u bedclock.service --follow

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sudo systemctl status bedclock.service

sudo journalctl -u bedclock.service --follow

Customize tweaks

There are lots of knobs that can be tweaked to make the clock behave as you want. Most of these settings are located in the file called const.py. After making the changes, make sure to restart the application by typing the following command

sudo systemctl restart bedclock.service

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sudo systemctl restart bedclock.service

If you want to start it manually, use start_bedclock.sh

sudo systemctl stop bedclock.service
~/bedclock.git/bedclock/bin/start_bedclock.sh

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sudo systemctl stop bedclock.service
~/bedclock.git/bedclock/bin/start_bedclock.sh

Just like the time you ran the matrix demo, press the Control-C keys to stop the program and get back to the command line.

MQTT

If you have an MQTT broker that your bedclock can talk to, you can enable it via the mqtt_enabled setting in the const.py file.

That file will be located under the following directory:

# Edit file and modify the following parmameters:
# mqtt_broker_ip =
# mqtt_enabled = True

/bin/nano  ~/bedclock.git/bedclock/const.py

Receiving events published by the bedclock application

# Install mqtt client to poke bedclock via mqtt broker
$ sudo apt-get install -y mosquitto-clients

$ mosquitto_sub -v -h ${MQTT_BROKER} -t "/bedclock/motion" -t "/bedclock/light"
/bedclock/motion on
/bedclock/motion off
/bedclock/light 365

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# Install mqtt client to poke bedclock via mqtt broker
$ sudo apt-get install -y mosquitto-clients

$ mosquitto_sub -v -h ${MQTT_BROKER} -t "/bedclock/motion" -t "/bedclock/light"
/bedclock/motion on
/bedclock/motion off
/bedclock/light 365

Configuring the clock to stay awake in the dark

If you don't want the clock to go blank when the room is dark, you can change its default behavior in const.py by setting scr_stayOnInDarkRoomDefault = True. Or via MQTT, as shown below:

$ mosquitto_pub -h ${MQTT_BROKER} -t /bedclock/stay -r -m "on"
$ mosquitto_pub -h ${MQTT_BROKER} -t /bedclock/stay -r -m "off"

# to clear topic from broker and use const.scr_stayOnInDarkRoomDefault
$ mosquitto_pub -h ${MQTT_BROKER} -t /bedclock/stay -r -n

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$ mosquitto_pub -h ${MQTT_BROKER} -t /bedclock/stay -r -m "on"
$ mosquitto_pub -h ${MQTT_BROKER} -t /bedclock/stay -r -m "off"

# to clear topic from broker and use const.scr_stayOnInDarkRoomDefault
$ mosquitto_pub -h ${MQTT_BROKER} -t /bedclock/stay -r -n

Remove/disable unnecessary services

RPI Zero W handles the display just fine but it does not hurt to help it out by disabling unused things that compete for cycles. These were the ones I did on my setup, based on Henner's advice:

sudo systemctl disable avahi-daemon && \
sudo systemctl stop avahi-daemon && \
sudo apt-get remove -y bluez bluez-firmware pi-bluetooth triggerhappy && \
echo ok

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sudo systemctl disable avahi-daemon && \
sudo systemctl stop avahi-daemon && \
sudo apt-get remove -y bluez bluez-firmware pi-bluetooth triggerhappy && \
echo ok

Safely Shutdown setup

Abruptly cutting power to the Pi can cause the files in the SD card to become corrupt. So, we suggest safely shutting down the Pi. There is a dedicated guide for enabling Read-Only mode, which will allow you to quickly turn off the Pi without risking corrupting the SD card.

Check out this video to see the bedclock in action