# PRRPC — Pico Real Rich Presence

> Physical status monitor for Linux environments. Displays contextual active application information on a secondary LCD screen powered by RP2040.

**Live:** [prrpc.jrodriiguezg.link](https://prrpc.jrodriiguezg.link)  
**GitHub:** [jrodriiguezg/PRRPC](https://github.com/jrodriiguezg/PRRPC)

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## Overview

PRRPC is an open-source hardware/software project that bridges your Linux desktop with a physical secondary display. A Python service running on the host PC detects the currently active application via GNOME's accessibility API and sends that information over USB serial to an RP2040 microcontroller, which renders a graphical icon on a 1.69" IPS LCD screen.

It operates in two distinct modes:

| Version | Mode | Description |
|---|---|---|
| V1 | Auto Monitoring | Automatic active-app detection and display |
| V2 | MacroDeck | Interactive mode with browser-based emoji control |

## Architecture

```
Host PC (Linux / GNOME / Wayland)
          │
          │  pyatspi focus events
          ▼
  Python Service (monitor_pc.py)
          │
          │  Serial (USB-C)
          ▼
    RP2040-Zero (MicroPython)
          │
          │  SPI
          ▼
  1.69" IPS LCD (ST7789, 240×280)
```

**Key property:** The serial communication model means **zero CPU polling** on the host — events are pushed only when the active window changes.

## Features

### V1 — Auto Monitoring

- GNOME window focus detection via `pyatspi`
- Event-driven serial communication (no polling, near-zero CPU impact)
- Real-time application switching reflected on the LCD
- Session time tracking per application

### V2 — MacroDeck

- Flask web server on `localhost:5000`
- Browser-accessible emoji selector UI
- Manual display override from any device on the LAN
- Multi-threaded architecture
- Optimized 100×100px RGB565 image assets

## Hardware Specifications

| Component | Specification |
|---|---|
| Microcontroller | RP2040-Zero (or compatible Raspberry Pi Pico) |
| Firmware | MicroPython |
| Display | 1.69" IPS LCD, ST7789 controller, 240×280px |
| Interface | SPI (display) + USB-C (data + power) |
| Host OS | Linux with GNOME desktop (Wayland/X11) |
| Host Language | Python + pyatspi |

## Software Requirements

- **Host:** Python 3, `pyatspi`, `pyserial`
- **V2 additionally:** `flask`
- **Microcontroller:** MicroPython with `st7789` display driver

## App Mapping (V1)

```python
# Example: Adding a new app in monitor_pc.py
APPS_MAPPING = {
    "Code":      "VSCODE",
    "Firefox":   "FIREFOX",
    # Map window focus keyword to an internal ID
    "Obsidian":  "NOTAS"
}
```

## Web Control API (V2)

```python
# V2: Web control API snippet
@app.route('/set_emoji/<emoji_id>')
def set_emoji(emoji_id):
    # Sends manual Emoji command via serial
    send_to_serial(emoji_id.upper())
    return {"status": "success"}
```

## Gallery

The device has been tested and demonstrated with the following applications on Fedora Linux:
- **VS Code** — Development environment detection
- **Firefox** — Web browsing session tracking
- **Terminal** — System shell activity
- **YouTube Music** — Media playback tracking

## Tested On

- **OS:** Fedora Linux (GNOME, Wayland)
- **Hardware:** RP2040-Zero + 1.69" ST7789 LCD

## Support

☕ [Support on Ko-fi](https://ko-fi.com/jrodriiguezg)

## Author

**Juan Raul Rodriguez Gil** — Built with passion for Linux & Hardware  
[jrodriiguezg.link](https://jrodriiguezg.link) | [GitHub](https://github.com/jrodriiguezg) | [Instagram](https://www.instagram.com/jrodriiguezg.link/?hl=es)

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© 2026 Juan Raul Rodriguez Gil