Hologram Nova Starter Kit: Comprehensive Raspberry Pi Setup & Sensor Integration Guide

New to Nova? New to Raspberry Pi? New to Python? This tutorial walks you through every step of the Hologram Nova Starter Kit.

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This tutorial is part of the official Hologram Nova Starter Kit, available at Hologram.io.

Setup a Raspberry Pi – Headless

Note: If you already have Raspbian on an SD card and can SSH into it, skip to the next section.

A headless setup means the Pi boots without a monitor, keyboard, or mouse. All configuration happens from your primary computer via SSH.

1. Download and burn the Raspbian OS to SD

Key points to keep in mind:

• Raspbian is a Debian derivative tailored for Raspberry Pi’s ARM architecture.
• Both Lite (no desktop) and Full versions work; Lite is sufficient for this tutorial.
• NOOBS is unnecessary and adds extra steps.
• Use Etcher, a cross‑platform tool, to flash the OS image.

Download Raspbian: raspbian.org/downloads/raspbian

Download/install Etcher: etcher.io

Burning Raspbian to SD Card:

• Insert the SD card into your computer.
• Open Etcher.
• Choose the downloaded Raspbian zip file as the OS.
• Select the SD card as the target drive.
• Click “Flash!”.
• Etcher’s interface will look similar to the screenshot below.

2. Configure Raspbian

After flashing, re‑mount the SD card to your computer. Open a terminal and navigate to the boot partition.

cd /Volumes/boot

Enable SSH by creating an empty file:

touch ssh

Pre‑configure Wi‑Fi so the Pi joins your network on boot. The Pi only supports 2.4 GHz.

sudo nano wpa_supplicant.conf

Paste the following, replacing the placeholders with your credentials:

country=US 
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev 
update_config=1 
network={
      ssid="**your-wifi**"
      psk="**your-password**"
      key_mgmt=WPA-PSK
}

For unsecured networks:

country=US 
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev 
update_config=1 
network={
    ssid="**your-wifi**"
    key_mgmt=NONE
}

Save and exit Nano with CTRL+X, then Y and ENTER. Eject the SD card and insert it into the Pi.

3. Connect to the Pi over Wi‑Fi SSH

Power the Pi using the supplied 5 V 2.4 A adapter. Wait a minute for the network to come up.

From your host computer, open a terminal and SSH in:

ssh pi@raspberrypi.local

Password: raspberry.

Troubleshooting:

• Device not found? Verify the Wi‑Fi credentials and ensure the Pi is on a 2.4 GHz network.
• Multiple Pis with the same hostname? SSH using the Pi’s local IP: ssh [email protected].

Once logged in, run the Raspberry Pi configuration tool:

sudo raspi-config

In the menu, perform the following actions:

• 7 – Advanced Options → A1 Expand Filesystem
• 5 – Interfacing Options → SPI (enable I2C if needed)
• 1 – Change User Password
• 2 – Hostname (choose a memorable name)
• Select Finish and allow the Pi to reboot.

After reboot, SSH back in using the new hostname: ssh [email protected].

4. Install Dependencies

Update the Pi’s package list:

sudo apt-get update

Install essential packages:

sudo apt-get install git git-core build-essential python-dev python-openssl python-smbus python3-pip python-pip screen

Install Hologram’s Python SDK:

curl -L hologram.io/python-install | bash

Verify the CLI version:

hologram version

You should see a version greater than 0.6.0. Congratulations – the Pi is now ready.

Lesson 1 – Blink an LED

We’ll use the Pi’s GPIO pins (BCM numbering). For a quick refresher, see the StackOverflow GPIO guide. The following pinout will be referenced.

If you’re new to breadboards, watch this ScienceBuddiesTv video.

In this lesson we’ll set a GPIO pin as an output to control an LED.

Wiring Diagram

Connect the LED via a 220 Ω resistor. Power is typically the red wire; ground the black wire. Always disconnect power before wiring.

Reconnect power, wait a minute, and re‑establish SSH.

Run the Code 🏃💨

Clone the starter‑kit repository:

git clone https://github.com/benstr/nova-starter-kit.git

Verify the folder exists:

ls nova-starter-kit/

Execute the blink script:

sudo python nova-starter-kit/01_blink/main.py

Enter the number of blinks when prompted. The LED should toggle accordingly.

View the source files:

cat nova-starter-kit/01_blink/main.py

cat nova-starter-kit/01_blink/myLED.py

Be Ambitious!

Explore additional functions in myLED.py by editing main.py and rerunning the script.

sudo nano nova-starter-kit/01_blink/main.py

Lesson 2 – Read a Digital Sensor

We’ll add a DHT11 humidity/temperature sensor. Adafruit’s DHT library simplifies data retrieval.

Learn more about DHT sensors at Adafruit DHT page.

Wiring Diagram

Use a 10 kΩ pull‑up resistor.

Remove power before wiring.

Reconnect power, wait a minute, and re‑establish SSH.

Run the Code 🏃💨

Verify the sensor folder:

ls nova-starter-kit/02_digital_sensor/

Install Adafruit’s DHT library:

git clone https://github.com/adafruit/Adafruit_Python_DHT.git

sudo python Adafruit_Python_DHT/setup.py install

Test the sensor:

sudo Adafruit_Python_DHT/examples/AdafruitDHT.py 11 21

Run the lesson script:

sudo python nova-starter-kit/02_digital_sensor/main.py

The LED will blink three times and display temperature/humidity.

cat nova-starter-kit/02_digital_sensor/main.py

cat nova-starter-kit/02_digital_sensor/myDHT.py

Lesson 3 – Read an Analog Sensor

The Pi can only read digital signals. To capture analog data we’ll use an MCP‑3008 ADC to convert a photoresistor’s output.

The MCP‑3008 offers eight channels; we’ll use channel 0. Adafruit’s MCP3008 library will handle communication.

Wiring Diagram

Ensure the MCP‑3008’s notch faces left. Double‑check all connections.

Remove power before wiring.

Reconnect power, wait a minute, and re‑establish SSH.

Run the Code 🏃💨

Verify the analog sensor folder:

ls nova-starter-kit/03_analog_sensor/

Install the MCP3008 library:

git clone https://github.com/adafruit/Adafruit_Python_MCP3008.git

sudo python Adafruit_Python_MCP3008/setup.py install

Run the analog sensor script:

sudo python nova-starter-kit/03_analog_sensor/main.py

The LED will blink four times and print temperature, humidity, and luminosity.

cat nova-starter-kit/03_analog_sensor/main.py

cat nova-starter-kit/03_analog_sensor/myMCP.py

Lesson 4 – Trigger with a Button

To avoid manual SSH sessions, we’ll wire a button to trigger sensor reads and set the script to run automatically at boot.

Wiring Diagram

The wiring is straightforward – connect the button to a GPIO pin and pull‑up resistor.

Reconnect power, wait a minute, and re‑establish SSH.

Run the Code 🏃💨

Verify the button folder:

ls nova-starter-kit/04_button/

Run the button script:

sudo python nova-starter-kit/04_button/main.py

The script sits in an infinite loop, waiting for a button press. Press CTRL+C to stop.

cat nova-starter-kit/04_button/main.py

Run the Code at Startup 🔌🏃💨

Edit /etc/rc.local to launch the script on boot:

sudo nano /etc/rc.local

Add the line before exit 0:

sudo python /home/pi/nova-starter-kit/04_button/main.py &

Save, reboot:

sudo reboot

After reboot, pressing the button should trigger four LED blinks.

Lesson 5 – Send Data through Wi‑Fi

Now the script runs at boot, but we still want to view data locally. We’ll forward sensor readings to Hologram’s Data Engine.

If your SIM isn’t activated, do so at dashboard.hologram.io/activate.

On the Hologram dashboard, open your Nova device, navigate to Configuration, click “Show Router Credentials”, generate an 8‑digit key, and keep it handy.

Edit the credentials file:

sudo nano nova-starter-kit/credentials.json

Replace the placeholder with the generated key.

Update /etc/rc.local to launch the cloud script:

sudo nano /etc/rc.local

sudo python /home/pi/nova-starter-kit/05_cloud/main.py &

Reboot:

sudo reboot

After a few minutes, pressing the button will send data to the cloud. Verify the results at dashboard.hologram.io.

View the cloud script:

cat nova-starter-kit/05_cloud/main.py

Lesson 6 – Send Data through Cellular

Deploying in Wi‑Fi‑poor environments is straightforward. After assembling the Nova and inserting the SIM, the two LEDs on the Nova indicate network readiness.

Edit /etc/rc.local to use the cellular script:

sudo nano /etc/rc.local

sudo python /home/pi/nova-starter-kit/06_cellular/main.py &

Reboot:

sudo reboot

Verify data transmission at dashboard.hologram.io.

View the cellular script:

cat nova-starter-kit/06_cellular/main.py

You’ve now built a weather‑sensor robot that can operate worldwide via cellular.

Source: Hologram Nova Starter Kit