Raspberry Pi Zero W Python Development Environment

This project describes how to setup a Raspberry Pi Zero W for remote Python development using VSCode.
Once setup, you can develop and single-step debug Python scripts from your local PC and execute on a remote Raspberry Pi Zero W.

The following was adapted from: https://bitbucket.org/jIRI/rasp-pi-zerow-vscode/src/master/

NOTE: See rpi0_tflite_picamera which is provides a more realistic dev environment.

Hardware

This assumes you have a Raspberry Pi Zero W (W = built-in wifi/bluetooth support). There a tons of dev kits available, e.g.: https://www.canakit.com/raspberry-pi-zero-wireless.html?src=raspberrypi

NOTE: You need a micro SD card, the RPI board-only doesn't have onboard ROM to store the OS.

NOTE: You might also need a micro SD reader if you computer doesn't have one. e.g.:
https://www.amazon.com/s?k=usb+micro+sd+card+reader

Raspbery Pi Setup

1) Program Raspberry Pi OS to SD Card

Plug the SD card in your computer's SD card reader, then
use the Raspberry PI Imager to program RPI OS to your micro SD card:
https://www.raspberrypi.org/software/

It's recommended to start with the default OS (with desktop support) before getting crazy with RPI OS-lite.

2) Enable network over USB

After programming RPI OS from setup 1, unplug the SD card, then plugin it back into your computer. Go to your file explorer, you should see the SD card be mounted as a new drive (at least on Windows) with a description as: boot.

Open the SD card 'boot' drive and edit the following files in the root of the SD card:

config.txt:
Open config.txt and to the end add:

dtoverlay=dwc2

More details about config.txt here:
https://www.raspberrypi.org/documentation/configuration/config-txt/

cmdline.txt:
Open cmdline.txt, just after rootwait add:

modules-load=dwc2,g_ether

ssh
Create empty file named ssh in root of the SD card

3) Install mDNS onto your computer

If you're using Windows, install: https://support.apple.com/kb/DL999?viewlocale=en_US&locale=en_US

If you're using Linux, install:

sudo apt-get install avahi-daemon

4) Start the Raspberry Pi Zero W

Unmount the SD card an plug it into the RPI. Then plug the USB micro into the RPI's USB port (not PWR) and the other side into your computer.

5) Configure sharing on your Windows network adapter so Pi can see the Internet

Go somewhere around Control Panel -> Network and Internet -> Network Connections
Double click your default network connection, click Properties..., tab Sharing

6) Open an SSH session to the RPI

On Windows, PuTTY is recommended: http://www.putty.org/

Connect over SSH (port 22) with connection string: pi@raspberrypi.local
Accept certificate
Default password is raspberry

7) Configure Wi-Fi

From the SSH session, issue the command:

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

From the opened file editor, add the following to the end:

network={
  ssid="MY_NETWORK_NAME"
  psk="MY_NETWORK_PASSWORD"
}

Updating MY_NETWORK_NAME and MY_NETWORK_PASSWORD with your Wi-Fi info.

Then, Ctrl+O to save, Ctrl+X to exit nano.

Next, issue the command:

sudo wpa_cli reconfigure

Then issue the command:

sudo reboot

This will reboot the RPI and close your SSH session. You'll need to start a new SSH session for the subsequent steps.

8) Create the workspace directory

From the RPI SSH session (step 7), issue the command:

mkdir workspace
chmod 0777 workspace
cd workspace
pwd

Which should create the directory:

/home/pi/workspace

9) Update Pi, install samba, config samba

From the RPI SSH session (step 7), issue the commands:

sudo apt-get update
sudo apt-get install -y samba samba-common-bin

Then issue:

sudo nano /etc/samba/smb.conf

Add to the end of file:

[workspace]
path=/home/pi/workspace
browsable=yes
writable=yes
only guest=no
create mask=0777
directory mask=0777
public=yes

Then issue:

sudo service smbd restart

In your local file explorer, you should be able to open (on Windows):

\\RASPBERRYPI\workspace

10) Install debugpy on the Pi to be able debug remotely

We use debugpy to enable Python remote debugging.

From the RPI SSH session (step 7), issue the command:

sudo pip3 install debugpy==1.3.0

(You may be able to use a newer version, but that version worked for me)

NOTE: This repo uses Python3, hence pip3.

12) Resize your Pi partition to use all available space on SD card

From the RPI SSH session (step 7), issue the commands:

sudo raspi-config --expand-rootfs
sudo reboot

Prepare VSCode Workspace

1) Install the dirsync Python package

We use the dirsync Python package to automatically synchronize files between the local workspace and the remote RPI workspace.

Issue the following command from a local terminal to install the package:

pip3 install dirsync

After installing, the dirsync command should be accessbile to VSCode.

2) Open VSCode Workspace

Assuming you cloned this repo, open the VSCode 'workspace' that is at the root of this repo: workspace.code-workspace then install the 'Recommended Extensions'.

3) Map Network Drive

If using Windows, map the \\RASPBERRYPI\workspace network drive, more details here
After this is complete, you should have a new drive, e.g. Z:\\ that points to your RPI's /home/pi/workspace directory.

This is required so we can easily sync the local workspace with the RPI's workspace.

4) Update tasks.json

Open <repo root>/.vscode/tasks.json,

In the sync-workspace task, update the arguments as necessary for your workspace.
At a minimum, you may need to change z:/ to your networking mapping drive from the previous step.

Run the debugger

That's it! Running the Debug Python debug configuration should:

1. Synchronize the local workspace with the RPI's workspace (assuming the network drive is properly mapped)
2. Start the main.py python script with remote debugging enabled
3. Cause VSCode to connect to the debug server and allow for single-stepping in the Python script as if it were running locally