# 🫁 Capnograph Prototype – Real-Time EtCO₂ Monitoring

This project is a prototype implementation of a capnograph module I developed as part of a biomedical device when I was working on Gätsimed. It demonstrates how data from a capnograph sensor is received, processed, and visualized in real time using **C++** and **QML (Qt)**. This version was created before integrating the functionality into the production environment.

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## 🔍 What is a Capnograph?

A **capnograph** measures the concentration of CO₂ in exhaled air over time — a critical parameter in patient monitoring. It outputs both a waveform (capnogram) and key respiratory values such as:

- **EtCO₂** (End-tidal CO₂)
- **Respiratory Rate**
- **Inhaled/Exhaled CO₂ Concentration**

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## ⚙️ How It Works

### 📤 Serial Communication (C++)

- Connects to the capnograph sensor via a serial port.
- Listens for incoming data packets.
- Identifies and parses two packet types:
  - **Gas concentration data** for waveform plotting.
  - **Calculated values** like EtCO₂ and respiration rate.
- Validates packet integrity (start/stop bytes, checksums).
- Interpolates data to ensure smooth waveform display.
- Emits Qt signals with parsed values to update the UI in real time.

### 💻 User Interface (QML)

- Displays the capnogram curve dynamically.
- Shows live values for EtCO₂ and respiratory rate.
- Built using QML for a responsive and clean UI.