https://www.geometrics.com/product/magarrow/

To use the MagArrowConverter:

Run “MagArrowConverterInstaller.exe” to install the converter. It is recommended NOT to install the converter on the default C:\Program Files\ directory since some computer may not allow users to create files in this directory. Open Windows Command (“cmd”) and enter the directory where the converter is installed. Type MagArrowConverter and press Enter key. A short instruction of how to use the converter will be printed out.
If you run it from a different directory, type the full path, e.g. "C:\ Geometrics\MagArrowConverter\MagArrowConverter" (assuming the program is installed in C:\ Geometrics\MagArrowConverter\ directory). Note that to change the installation directory, you will have to un-installed the program first and then re-install and set up the directory. A typical example command: …\MagArrowConverter type=MA1 format=csv1 input=”C:\test\test.magdata” output=”C:\test\test.csv” decimation=10 A new csv file with sample rate of 10Hz will be created in C:\test directory from test.magdata file. After you become familiar with MagArrowConverter command, you can write a simple Batch Script to bulk process MagArrow .magdata files.

An example batch code which searches for .magdata files in "C:\MagArrowData" folder and converts all files to .csv files at 10Hz is attached below.