Harmonizing Circuit Design and EMC DesignPart 22 EMC Calculation Methods and EMC Simulations (7): Graphical User Interfaces (GUIs)

Hello! I’m Inagaki, at ROHM

In this 22nd article I’d like to change the subject just a bit and talk about graphical user interfaces (GUIs) that are actually used in calculations and simulations of electromagnetic compatibility (EMC).

When using a shell script (.bat file) to execute in-house tools and commercially available tools, methods in which commands are input from the Windows command shell are probably the most common. However, when commands must be input each time and multiple commands are used, confusion may result when a third party is using the software. In order to eliminate such concerns, in this article I’d like to introduce GUI menus that use a program called Gnu AutoHotkey (open source). This was originally a tool for allocating shortcut keys (hotkeys), but it also includes GUI creation functions. It’s probably best to have a look for yourself. The overall menu for EMC simulations operates in this way. Upon clicking the .ahk file, the program starts.

GUI Display of Gnu AutoHotkey, Computational Electromagnetics (CEM)

From this menu, upon clicking on the electromagnetic compatibility (EMC) standard for EMC simulation, a panel to execute calculation verification for the corresponding standard appears. Here we consider the example of the IEC 61967-4 standard 1 Ω/150 Ω law. The panel is divided into the major categories Setup, Optimization (optimization of differential correction values), and Prediction (calculation prediction). Upon clicking on the boxes from left to right and from upper to lower, the relevant folders are opened, automated command execution is performed, and so on. Thus calculation verification is completed using mouse operations only, without the need to input any commands.

GUI Display of Gnu AutoHotkey, execution panel for IEC 61967-4 calculation verification

It should be noted that, once one understands the format of this Gnu AutoHotkey tool, it can be used ① without the need for any special programming knowledge, ② using very small ASCII files, ③ with very fast startup and operation, ④ with the ability to compile (convert to an .exe file) code if necessary, and moreover it is ⑤ open source (free). To run the tool, one simply clicks to start up the command shell automatically, and commands are input automatically. The function syntax is extremely simple and easy to understand. Upon actually using it, you will find that is a wrapper type tool that can be used for much more than just EMC simulations. A number of specialized layout arrangement tools have also been released, and are very easy to use. Please give them a try.

Gnu AutoHotkey source code, IEC 61967-4 calculation verification
(click the image to enlarge)

Thank you for your kind attention.