Sample code is not provided from the official website, but specifications and source code are available. I hope you find it helpful.
There is only one point to note. Since the data is transmitted in little endian, it is not in the network byte order generally called.
The source code can be obtained with the following command on Ubuntu. apt source hark-core
In the case of Windows environment, it is probably easy to download from the following URL. http://archive.hark.jp/harkrepos/dists/bionic/non-free/source/
You can download any version by clicking the following file name on the browser. The <version> will be in the form of “x.x.x”. hark-core_<version>.tar.gz