Why SPIdev for Windows is a Game-Changer: Everything You Need to Know

Spidev is a module under Linux. It is present on the Linux kernel’s SPI device driver. Spidev for Windows doesn’t exist but can be installed separately.

Why spidev is not supported in Windows by default?

This happens due to a couple of reasons:

• Linux supports Spidev in a better way as compared to Windows.
• It is thought to be a complex library to understand. Therefore, it hasn’t been pre-installed or provided by default.
• In case of incorrect installation, it will pose security risks to the system.

How to use spidev for Windows

Commonly used ways to use Spidev for Windows include the following methods:

• You may use the SPI driver library, which is provided by third-party software.
• Nowadays, USB-to-SPI adapters are also available.
• You can create an SPI object with Windows.Devices.Spi API.
• Install a Windows driver for using SPI.

Adafruit SPI library is a commonly used third-party library to use spidev on Windows. Apart from this, software development kits (SDK) are available. These kits include documentation for the library, which helps to access SPI on Windows.

Preferred methods for SPI installation

It depends on the needs and system specifications of a programmer.

• For UWP app developers, Windows.Devices.Spi API works best.
• For setting up a desktop application, utilize other modes.

Using Adafruit SPI library

It is still in the development phase. So it may not support all features of SPI.

import adafruit_spi

# Create an SPI object using the SPI bus number and device number
spi = adafruit_spi.SPIDevice(0, 0)

# Write data to the SPI device
spi.write([0x01, 0x02, 0x03])

# Read data from the SPI device
data = spi.read(3)

# Print the read data
print(data)

Using Windows.Devices.Spi

 The Universal Windows Platform (UWP) provides this API. The Windows.Devices.Spi can also be used to access the SPIDEV on Windows. It is based on C++, C#, etc.

// Create an SPI device object
SpiDevice spiDevice = await SpiDevice.FromIdAsync("SPI0\\0");

// Write data to the SPI device
byte[] writeData = new byte[] { 0x01, 0x02, 0x03 };
spiDevice.Write(writeData);

// Read data from the SPI device
byte[] readData = new byte[3];
spiDevice.Read(readData);

// Print the read data
foreach (byte b in readData)
{
    Console.WriteLine(b);
}

Other methods of installation

Apart from these methods, the following can be accepted too.

• WinSPI library can also be used for (UWP) SPI API
• py-spidev works like the Linux spidev library. It utilizes the WinSPI library to access SPI devices.
• spidev-sys is centered on Win32 API. You can think of it as an alternative to the aforementioned libraries.

pip install winspi py-spidev
#or github cloning
git clone https://github.com/doceme/py-spidev
cd py-spidev
python setup.py install

After installing the library, you can work on SPI devices on Windows. So, once you have cloned the library, this code helps to read 15 bytes from the spi device.

import spidev
spi = spidev.SpiDev()
spi.open(0, 0)
data = spi.readbytes(15)
spi.close()

Tips for Spidev installation

Check the following tips to ensure correct installation. This will result in error-free working of Spidev on Windows.

• Ensure connections are fine.
• Check updates for drivers.
• Check the compatibility of third-party apps on your Windows.
• Go through the library documentation
• Test the code before working on a project.
• See if the correct SPI device file exists.
• Correct SPI mode and speed (as per the system) should exist.
• Restart your device if any problem persists.

Limitations of spidev on Windows

Windows doesn’t work that well with spidev. One should, for obvious reasons, prefer Linux. Some devices can’t work properly with spidev on Windows.

Can we use spidev by installing the SubLinux system in Windows itself?

We can use spidev by installing the SubLinux system in Windows. You can achieve this by doing the stepwise procedure:

• Open cmd and enter wsl –install
• Choose a Linux distribution and then open the Linux terminal.
• Enter wsl in the Linux terminal
• Lastly, use this command: sudo apt install spidev

This will ensure communication with the SPI device.

FAQs

Conclusion

We know that spidev is Linux-based. However, we can install it on Windows too. Through this blog, you must have got to know how you can work on spidev on Windows OS. The blog covers certain tips to ensure correct installation.