# Agilent VSpin

The VSpin centrifuge is controlled by the {class}`~pylabrobot.centrifuge.vspin_backend.VSpinBackend` class.

```python
from pylabrobot.centrifuge import Centrifuge, VSpinBackend
await cf.setup()
cf = Centrifuge(name = "centrifuge", backend = VSpinBackend(device_id="YOUR_FTDI_ID_HERE"), size_x= 1, size_y=1, size_z=1)
```

You need to calibrate the bucket 1 position for every vspin. You can do that by opening the door (`cf.open_door()`), manually rotating the buckets to align bucket 1 with the door, and then setting bucket 1 position to the current position with `cf.backend.set_bucket_1_position_to_current()`. This will save the calibration for the current centrifuge to disk (based on the usb serial number).

```python
await cf.open_door()
# Manually rotate buckets to align bucket 1 with door
await cf.backend.set_bucket_1_position_to_current()
```

Start spin cycle:

```python
await cf.start_spin_cycle(g = 800, duration = 60)
```

Going to buckets:

```python
await cf.go_to_bucket1()
await cf.go_to_bucket2()
```

## Loader

The VSpin can optionally be used with a loader (called Access2). The loader is optional because you can also use a robotic arm like an iSWAP to move a plate directly into the centrifuge.

Here's how to use the loader:

```python
import asyncio

from pylabrobot.centrifuge import Access2, VSpinBackend
v = VSpinBackend(device_id="YOUR_VSPIN_FTDI_ID_HERE")
centrifuge, loader = Access2(name="name", vspin=v, device_id="YOUR_LOADER_FTDI_ID_HERE")

# initialize the centrifuge and loader in parallel
await asyncio.gather(
  centrifuge.setup(),
  loader.setup()
)

# go to a bucket and open the door before loading
await centrifuge.go_to_bucket1()
await centrifuge.open_door()

# assign a plate to the loader before loading. This can also be done implicitly by for example
# lh.move_plate(plate, loader)
from pylabrobot.resources import Cor_96_wellplate_360ul_Fb
plate = Cor_96_wellplate_360ul_Fb(name="plate")
loader.assign_child_resource(plate)

# load and unload the plate
await loader.load()
await loader.unload()
```

## 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. Installing libftdi

#### 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 have similar packages.

#### 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.

**Configuring the Driver with Zadig**

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.

### 2. 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).

You’re now ready to use your VSpin centrifuge with `pylabrobot`!