Word Clock

Making a Raspberry Pi Image

Download and prepare SD Card

Download Raspian Stretch Lite from https://www.raspberrypi.org/downloads/raspbian/ Write image using Win32DiskImager

Boot and set up Wifi

https://www.piborg.org/blog/pi-zero-wifi-bluetooth sudo nano /etc/wpa_supplicant/wpa_supplicant.conf add to bottom of file:

network={
      	ssid="Network Name"
      	psk="password"
}

Enable SPI, SSH, I2C etc.

sudo raspi-config

• Go to interfacing -> enable SSH
• Go to interfacing -> enable I2C
• Go to interfacing -> enable SPI
• Change Boot Options -> Desktop/Cli -> Console Autologin

Get latest updates to the OS

sudo apt-get update && sudo apt-get -y upgrade
sudo apt-get -y install git python-smbus i2c-tools python-dev python-pip build-essential scons swig apache2 php libapache2-mod-php bluez-tools

Bluetooth

See https://raspberrypi.stackexchange.com/questions/29504/how-can-i-set-up-a-bluetooth-pan-connection-with-a-raspberry-pi-and-an-ipod

sudo vi /etc/systemd/network/pan0.netdev

[NetDev]
Name=pan0
Kind=bridge

sudo vi /etc/systemd/network/pan0.network

[Match]
Name=pan0

[Network]
Address=10.1.1.1/24
DHCPServer=yes

sudo vi /etc/systemd/system/bt-agent.service

[Unit]
Description=Bluetooth Auth Agent

[Service]
ExecStart=/usr/bin/bt-agent -c NoInputNoOutput
Type=simple

[Install]
WantedBy=multi-user.target

sudo vi /etc/systemd/system/bt-network.service

[Unit]
Description=Bluetooth NEP PAN
After=pan0.network

[Service]
ExecStart=/usr/bin/bt-network -s nap pan0
Type=simple

[Install]
WantedBy=multi-user.target

sudo systemctl enable systemd-networkd

sudo systemctl enable bt-agent

sudo systemctl enable bt-network

sudo systemctl start systemd-networkd

sudo systemctl start bt-agent

sudo systemctl start bt-network

sudo nano /etc/profile and add the lines:

sudo bt-adapter --set Discoverable 1

File editor web site

sudo rm /var/www/html/index.html

sudo ln -s /home/pi/WordClock/index.php /var/www/html/index.php

sudo ln -s /home/pi/WordClock/index.css /var/www/html/index.css

sudo chmod 777 /etc/wpa_supplicant/wpa_supplicant.conf

Git key gen

ssh-keygen -t rsa -C "[email address]" -b 4096

Set up Git config

git config --global user.email "[email address]"
git config --global user.name "[name]"

Add to Gitlab SSH key list

cat .ssh/id_rsa.pub

Get and build code

Dotstar

cd ~
git clone [email protected]:adafruit/Adafruit_DotStar_Pi.git
cd ~/Adafruit_DotStar_Pi
python setup.py build
sudo python setup.py install

WS2813

cd ~
git clone [email protected]:jgarff/rpi_ws281x.git
cd ~/rpi_ws281x 
scons
cd python
python ./setup.py build
sudo python setup.py install

WordClock

cd ~
git clone [email protected]:sgrubb/WordClock.git
cd ~/WordClock

Autostart clock on reboot

sudo vi /etc/profile and add the lines:

ps -caf | grep WordClock | grep -v grep | grep -v sudo
if [ $? -eq 0 ]; then
  echo "Clock is already running"
else
  echo "Start Clock."
  sudo python /home/pi/WordClock/main.py &
fi
cd /home/pi/WordClock;git pull

How to set up Wifi details using Bluetooth

• Reboot - Bluetooth will be discoverable for 3 minutes
• Connect via Bluetooth
• Open https://10.1.1.1 in a browser
• Change the wpa_supplicant.conf file

Network Time config:

https://wiki.archlinux.org/index.php/Systemd-timesyncd

sudo vi /etc/systemd/timesyncd.conf

[Time]
NTP=0.arch.pool.ntp.org 1.arch.pool.ntp.org 2.arch.pool.ntp.org 3.arch.pool.ntp.org
FallbackNTP=0.pool.ntp.org 1.pool.ntp.org 0.fr.pool.ntp.org

Set timezone

sudo dpkg-reconfigure tzdata

Real Time Clock (RTC)

https://learn.adafruit.com/adding-a-real-time-clock-to-raspberry-pi/set-rtc-time

sudo vi /boot/config.txt add to end of file:

dtoverlay=i2c-rtc,pcf8523

reboot them run sudo i2cdetect -y 1 which should show UU where 0x68 is disable fake clock:

sudo apt-get -y remove fake-hwclock
sudo update-rc.d -f fake-hwclock remove

sudo vi /lib/udev/hwclock-set and comment out:

#if [ -e /run/systemd/system ] ; then
# exit 0
#fi

run date to verify date

run sudo hwclock -w to write to RTC

Misc Notes

Types of strip

https://github.com/ManiacalLabs/AllPixel/wiki/Connecting-the-LEDs

WS2812 / WS2812B (Neopixels)

• Use WS2811 Controller strip hence sometimes referred to as "WS2812B strip with WS2811 controller"
• If one LED is broken, rest of strip won't work
• WS2812B has intelligent reverse connect protection and the power supply reverse connection does not damage the IC.
• Strict 800KHz data rate (bottleneck on long strands)
• 400Hz refresh/PWM rate
• Smetimes called APA104 (dont confuse with APA102 aka DotStar)

WS2813

• same controller as WS2812
• has BIN (Backup In) Pin

APA102 DotStar

• Built in PWM controller
• AKA LPD8806
• Uses SPI
• 32MHz data rate, 19.2KHz PWM rate

Debugging Wifi Issues

kill the wpa_supplicant process and run it manually:

sudo wpa_supplicant -c/etc/wpa_supplicant/wpa_supplicant.conf -iwlan0 -dd

Web administration console (Optional)

See http://www.webmin.com/deb.html

sudo sh -c 'echo "deb http://download.webmin.com/download/repository sarge contrib" > /etc/apt/sources.list.d/webmin.list'
wget -qO - http://www.webmin.com/jcameron-key.asc | sudo apt-key add -
sudo apt-get update
sudo apt-get install webmin