* https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=108134&p=923887#p923887
  * https://www.disk91.com/2015/technology/hardware/design-a-raspberry-pi-hat-shield/

{{https://www.raspberrypi.org/wp-content/uploads/2014/04/bplus-gpio.png}}

====== Flashing PiJack's EEPROM ======

<code>
sudo apt-get update
sudo apt-get install git

# edit /boot/config.txt and add the following to the end of the file (in this order)
dtparam=i2c=on
dtparam=i2c_vc=on

# reboot pi

# login as user pi
cd && mkdir git
cd git
# change 'hecko'to your BitBucket account name
git clone https://hecko@bitbucket.org/hotgluetech/pijack-production-tests.git
cd pijack-production-tests/bin
# 1 is serial number - written on every PiJack - serial number defines MAC address that will be generated for the device
sudo ./make_dtb.py -s 1

</code>