How to setup a Raspberry Pi Zero W and PGSparkLite from scratch

Prerequisites

• Raspberry Pi Zero W
• MicroSD card (minimum 4GB)
• Suitable standalone 5V power supply or PC USB port and micro USB cable

Setup

Prepare the microSD card

• Download and install Raspberry Pi Imager software (https://www.raspberrypi.org/software/)
• Burn the latest image of Raspberry Pi OS Lite to the micro SD card
• Before inserting microSD card into the Pi:
  • For headless setup, SSH should be enabled by placing a file named ssh, without any extension, onto the boot partition of the SD Card.
  • Follow the instructions here to configure WiFi on the Pi - https://www.raspberrypi.com/documentation/computers/configuration.html#setting-up-a-headless-raspberry-pi

Connect to the Pi

• Insert the microSD card and power up the Pi
• If necessary download and install an SSH client application (Putty is a good one, https://putty.org)
• SSH to the Pi using the address raspberrypi.local and login using the default credentials (change these ASAP)

Prepare the system files

Update existing packages

• Execute the following commands;

sudo apt update
sudo apt upgrade -y

Install system dependencies

sudo apt install git pi-bluetooth python3-bluez python3-pip -y

Install Eventlet (optional)

There can be a noticeable lag between changes made on the amp and updates to the web interface. This can be reduced by installing Eventlet to handle the socket communications. NOTE: Do not install Eventlet if you plan to debug the codebase in the future.

sudo pip3 install eventlet

Configure Bluetooth

• Execute the following command. This will open the Bluetooth configuration file in the nano text editor;

sudo nano /etc/bluetooth/main.conf

• Page down to the bottom of the file and add the following statement on a new line:

DisablePlugins = pnat

• Press Enter to add a line to the end of file
• Press Ctrl+O, then press Enter to save the changes
• Press Ctrl+X to exit the nano text editor

Install PGSparkLite

• Execute the following commands to download the latest version of PGSparkLite to /home/pi/PGSparkLite;

cd ~
git clone https://github.com/richtamblyn/PGSparkLite.git

• Install the application dependencies by executing the following commands;

cd PGSparkLite
sudo pip3 install -r requirements.txt --break-system-packages

Setup the PGSparkLite service

• Execute the following commands to allow the PGSparkLite startup script to run;

sudo chmod +x pgsparklite.sh

• Enter the following command to copy the PGSparkLite service to the system directory;

sudo cp pgsparklite.service /etc/systemd/system/pgsparklite.service
sudo systemctl enable pgsparklite.service

• Execute the following command to restart the Pi and start the PGSparkLite server;

sudo reboot

Test the PGSparkLite server

• Turn on your Positive Grid Spark 40 amp
• Open a web browser on a networked PC and enter http://raspberrypi.local:5000 into the address bar
• The PGSparkLite home page should now load
• Click the 'Connect' button to establish communication to your amp
• If connection is successful the controls page should now be shown

Next Steps

• To remove the need to specify the web port (default is 5000), look at installing nginx to reverse proxy the service to a common port.