Steps

1. you put together the hardware
2. you download the code from https://github.com/petrum/rpi
3. you prepare a local file with the WI-FI details
4. you run an installation script (provided) that will setup the micro SD card
5. you insert in the micro SD card in raspberry pi, power up and enjoy!

Step 1.

Buy the components:

• raspberry pi zero
• 8 Gb micro SD card
• wi-fi usb dongle
• two '4 in 1' MAX7219 LED dot matrix arrays
• micro USB cable
• power supply
• soldering tools
• jumper wires (they could come with the MAX7219)

1. you solder together the 2 LED arrays (in a chain, the out of one is the in of the other )
2. you solder the pins on the raspberry pi zero (for help check the 'GPIO pin-outs' section https://github.com/rm-hull/max7219)
3. you connect the input pins of one array with the raspberry pi

Board Pin Name 	Remarks 	RPi Pin	RPi Function
        1 VCC 	+5V Power 	      2 5V0
        2 GND 	Ground 	              6 GND
        3 DIN 	Data In 	     19 GPIO 10 (MOSI)
        4 CS 	Chip Select 	     24 GPIO 8 (SPI CE0)
        5 CLK 	Clock 	             23 GPIO 11 (SPI CLK)

Step 2.

You get the source code from github.com.

The code consists in a few bash scripts, and some Python code:

petrum@nuc ~$ mkdir github
petrum@nuc ~$ cd github/
petrum@nuc ~/github$ git clone https://github.com/petrum/rpi.git
Cloning into 'rpi'...
remote: Counting objects: 862, done.
remote: Compressing objects: 100% (14/14), done.
remote: Total 862 (delta 4), reused 0 (delta 0), pack-reused 848
Receiving objects: 100% (862/862), 4.43 MiB | 0 bytes/s, done.
Resolving deltas: 100% (517/517), done.
Checking connectivity... done.
petrum@nuc ~/github$ ls -ltr 
total 4
drwxrwxr-x 9 petrum petrum 4096 Oct 12 06:57 rpi
petrum@nuc ~/github$ cd rpi/weather2/
petrum@nuc ~/github/rpi/weather2[master]$ 

Step 3.

The installation script (rpi/weather2/install.sh) refers to the local ~/rpi-private/wpa_supplicant.conf.

You'll have to create this file (using rpi/net/wpa_supplicant.conf as a template), and type in your WI-FI details.

Note: After installation (step #4) this file should be available on the micro SD card, on the /boot FAT partition.

(so you can easily edit it even from a Windows laptop when you need to change the WI-FI details)

Step 4.

You need to download locally a recent version of the Raspbian OS.

Go to https://www.raspberrypi.org/downloads/raspbian/ and download the Raspbian Jessie Lite version.

Example:

/home/petrum/Downloads/2016-09-23-raspbian-jessie-lite.img

Note: you have to edit the rpi/weather2/install.sh script with your local image location.

Insert a micro SD card into your Linux desktop, cd to rpi/weather2 folder, and run the install.sh script.

The script will detect the memory card, and ask you for a confirmation if you want to proceed.

Please really pay attention at this step: the script will next use the 'dd' command to write the OS image file to the memory card.

Writing to the wrong card/disk could be disastrous!

(some say 'dd' stands for... disk destroyer!)

petrum@nuc ~/github/rpi/weather2[master]$ ./install.sh 
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 447.1G  0 disk 
├─sda1   8:1    0   156M  0 part /boot/efi
├─sda2   8:2    0    16G  0 part [SWAP]
├─sda3   8:3    0  39.5G  0 part /
└─sda4   8:4    0 391.5G  0 part /home
sdb      8:16   1   7.4G  0 disk 
├─sdb1   8:17   1    63M  0 part /media/petrum/boot                                                                                                      
└─sdb2   8:18   1   1.2G  0 part /media/petrum/3598...61dff1d
Using 'sdb'... Please confirm: [y/N]

Make sure there are no errors.

Step 5.

Enjoy!