> For the complete documentation index, see [llms.txt](https://docs.tychos.org/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tychos.org/docs/learn/hardware-devices.md).

# Connecting Hardware Devices

Tychos supports two types of hardware devices that can feed live sensor data directly into your simulation: **Vernier wireless sensors** (via Bluetooth) and **USB serial devices** (Micro:bit, Arduino, Raspberry Pi, ESP32, and others).

Open **Devices** from the **Settings** panel to connect and manage devices:

<figure><img src="/files/oIqdYES211wwfeVoWICi" alt=""><figcaption></figcaption></figure>

***

## Vernier Wireless Sensors

Vernier's wireless sensors connect over Bluetooth LE using Vernier's GoDirect technology. Click **+ Add Vernier** to scan for nearby sensors.

**Compatible devices:** Any Vernier GoDirect wireless sensor (force, temperature, motion, pH, etc.)

**Requirements:** Your browser must support Web Bluetooth (Chrome or Edge on desktop).

***

## USB Serial Devices

Click **+ Connect Serial Device** to connect any microcontroller that outputs data over USB as text. This uses the Web Serial API built into Chrome and Edge.

**Compatible devices include:**

* Micro:bit
* Arduino (Uno, Nano, Mega, etc.)
* Raspberry Pi (via USB serial)
* ESP32 / ESP8266
* Any device that sends text over a serial port

### Data Format

Your device should send data over serial at **115200 baud** in one of these formats:

**JSON object** (recommended for multiple values):

```
{"temperature": 22.5, "pressure": 1013.2}
```

**Key-value pairs** (one per line):

```
temperature:22.5
pressure:1013.2
```

**CSV** (values are labeled `col_0`, `col_1`, etc.):

```
22.5,1013.2
```

***

## Reading Device Data in Code

Once a device is connected, use `scenario.get_device(index)` to access it in your simulation code. Devices are indexed in the order they were connected (starting at `0`).

```python
# Get the first connected device
sensor = scenario.get_device(0)

# Read a value from the device
temp = sensor.data["temperature"]
```

The `data` dictionary is updated automatically each frame as new serial data arrives.

### Example (Python): Plotting live temperature

```python
# Setup
g = graph(title="Temperature")
sensor = scenario.get_device(0)

# Loop
if sensor:
    temp = sensor.data.get("temperature", 0)
    g.plot(x=t, y=temp, color="red")
```

### Multiple devices

```python
vernier = scenario.get_device(0)   # first connected
arduino = scenario.get_device(1)   # second connected

force = vernier.data.get("Force", 0)
angle = arduino.data.get("angle", 0)
```

***

## Arduino Example Sketch

Here is a minimal Arduino sketch that sends data in JSON format:

```cpp
void setup() {
  Serial.begin(115200);
}

void loop() {
  float temperature = analogRead(A0) * (5.0 / 1023.0) * 100.0;
  Serial.print("{\"temperature\":");
  Serial.print(temperature, 2);
  Serial.println("}");
  delay(100);
}
```

***

## Micro:bit Example (MakeCode / Python)

In MicroPython on the Micro:bit:

```python
from microbit import *
import utime

uart.init(baudrate=115200)

while True:
    x = accelerometer.get_x()
    y = accelerometer.get_y()
    uart.write('{"x":' + str(x) + ',"y":' + str(y) + '}\n')
    utime.sleep_ms(100)
```