add zadig tutorial for VSpin (#340)

Author: ben-ray

docs/user_guide/centrifuge.md

@@ -44,3 +44,108 @@ The VSpin centrifuge is controlled by the {class}`~pylabrobot.centrifuge.vspin.V
 from pylabrobot.centrifuge import Centrifuge, VSpin
 cf = Centrifuge(name = 'centrifuge', backend = VSpin(bucket_1_position=0), size_x= 1, size_y=1, size_z=1)
 ```
+
+### Installation
+
+The VSpin centrifuge connects to your system via a COM port. Integrating it with `pylabrobot` library requires some setup. Follow this guide to get started.
+
+#### 1. Preparing Your Environment
+
+- Windows:
+
+##### Find Your Python Directory
+
+To use the necessary FTDI `.dll` files, you need to locate your Python environment:
+
+1. Open Python in your terminal:
+   ```python
+   python
+   >>> import sys
+   >>> sys.executable
+   ```
+2. This will print a path, e.g., `C:\Python39\python.exe`.
+3. Navigate to the `Scripts` folder in the same directory as `python.exe`.
+
+##### **Download FTDI DLLs**
+
+Download the required `.dll` files from the following link:
+[FTDI Development Kit](https://sourceforge.net/projects/picusb/files/libftdi1-1.5_devkit_x86_x64_19July2020.zip/download) (link will start download).
+
+1. Extract the downloaded zip file.
+2. Locate the `bin64` folder.
+3. Copy the files named:
+   - `libftdi1.dll`
+   - `libusb-1.0.dll`
+
+##### Place DLLs in Python Scripts Folder
+
+Paste the copied `.dll` files into the `Scripts` folder of your Python environment. This enables Python to communicate with FTDI devices.
+
+- macOS:
+
+Install libftdi using [Homebrew](https://brew.sh/):
+
+```bash
+brew install libftdi
+```
+
+- Linux:
+
+Debian (rpi) / Ubuntu etc:
+
+```bash
+sudo apt-get install libftdi-dev
+```
+
+Other distros may have similar packages.
+
+#### 2. Configuring the Driver with Zadig
+
+- **This step is only required on Windows.**
+
+Use Zadig to replace the default driver of the VSpin device with `libusbk`:
+
+1. **Identify the VSpin Device**
+
+   - Open Zadig.
+   - To confirm the VSpin device, disconnect the RS232 port from the centrifuge while monitoring the Zadig device list.
+   - The device that disappears is your VSpin, likely titled "USB Serial Converter."
+
+2. **Replace the Driver**
+   - Select the identified VSpin device in Zadig.
+   - Replace its driver with `libusbk`.
+   - Optionally, rename the device to "VSpin" for easy identification.
+
+> **Note:** If you need to revert to the original driver for tools like the Agilent Centrifuge Config Tool, go to **Device Manager** and uninstall the `libusbk` driver. The default driver will reinstall automatically.
+
+#### 3. Finding the FTDI ID
+
+To interact with the centrifuge programmatically, you need its FTDI device ID. Use the following steps to find it:
+
+1. Open a terminal and run:
+   ```bash
+   python -m pylibftdi.examples.list_devices
+   ```
+2. This will output something like:
+   ```
+   FTDI:USB Serial Converter:FTE0RJ5T
+   ```
+3. Copy the ID (`FTE0RJ5T` or your equivalent).
+
+#### **4. Setting Up the Centrifuge**
+
+Use the following code to configure the centrifuge in Python:
+
+```python
+from pylabrobot import Centrifuge
+from pylabrobot.backends.vspin import VSpin
+
+# Replace with your specific FTDI device ID and bucket position for profile in Agilent Centrifuge Config Tool.
+backend = VSpin(bucket_1_position=6969, device_id="XXXXXXXX")
+centrifuge = Centrifuge(backend=backend)
+
+# Initialize the centrifuge.
+await centrifuge.setup()
+```
+
+You’re now ready to use your VSpin centrifuge with `pylabrobot`!