About

Ever need a serial port far away from your Raspberry Pi? Wish you could use WiFi to talk to a serial device without having to run a wire? This project is for you.

Installation

sudo npm i -g remote-serial-pico
remote-serial-pico i

Now a server is running on the Pi. If you plug in a Pico to the USB it will install the client code on the pico within 6 sec and make it a remote serial port.

/dev/pts/pty1

It's that easy to setup a remote serial port. Each time you plug in a pico, it will be the next ptyN on the list.

If you haven't already installed npm:

sudo apt update
sudo apt install nodejs npm

Background

Designed to facilitate communication between a remote device (such as a Raspberry Pi) and a device connected via serial to the Pico. It leverages TCP/IP networking to bridge data exchange between the Pico's serial interface and a networked environment. Extend this project using either the node-red-bridge or homebridge-tcp-smarthome.

Pico on-board LED status

LED blinks repeatedly during the WiFi connection process. Upon successful connection it turns off.
LED switches on again when connected to the TCP server.
LED blinks once upon receiving a command either from TCP server or a serially connected device.
LED turns off when disconnected from the TCP server.

Project Details

Curious about PtyServer?
- Detects Pico clients upon receiving first packet with pico_{N}, and creates a pseudo terminal(pty) for each Pico.
- Sends data available in pty to the respective Pico.
- Writes data received from Pico into corresponding pty.
- Log the commands and responses for each pico; check out the log:
```
tail -f /tmp/smartHome.log
```
Wondering how plugging Pico into the Pi installs client code in Pico?
- The udev rule (99-pico.rules) watches Pi's USB port for Pico connection.
- When a Pico is connected, it triggers another script PicoScriptDeployer.py to run on Pi.
And what exactly does PicoScriptDeployer do?
- It fetches wifi-ssid, password, IP, Pico-Serial-ID and updates the corresponding credentials on config.json. You can also manually update it.
- Deploys main.py and config.json to the most recently connected pico.
- You can observe the deployer log:
```
tail -f /tmp/deployer.log
```
Now, what's the role of the main code in Pico?
- Retrieves the network credentials and server details from the config.json.
- Upon TCP connection, sends its Serial-ID to the Pi in the first packet.
- Continuously checks for data in TCP and Serial; if it receives data from either, it sends that data to the other.

Visual Overview

Checkout the serial diagram:
Checkout the network diagram: SRC

Credits

Special thanks to Medical Informatics Engineering for their support throughout the development of this project, especially to Doug Horner for his invaluable guidance.