I recently confirmed that Mitsubishi’s iQ-R series PLCs continue to support the familiar MC Protocol for communication.

Initially, I tried using the official GX LogViewer to monitor the signals between the PLC and the motors. While it works, I found the interface and settings quite difficult to adjust and fine-tune for my specific needs. It was hard to capture the exact signal details I was looking for.

So, I decided to build my own!

To overcome this limitation, I leveraged the MC Protocol and used Python to develop a custom real-time Scope and Trend application. With this self-made tool, I can now observe the fine details of our motion control system much more intuitively and effectively—easily tracking metrics like encoder counts, actual motor position, and speed in real-time.

It was a really fun project! I’m genuinely glad Mitsubishi decided to keep the MC Protocol. This kind of flexibility allows developers to easily create custom plugins and tools, which significantly aids in deep system analysis and troubleshooting!