ASN.1
https://www.google.de/search?q=bacnet+asn.1
http://www.obj-sys.com/resources/links_asn1_info.php
https://lionet.info/asn1c/basics.html
https://ttsiodras.github.io/asn1.html
http://www.oss.com/asn1/resources/development-with-asn1/asn1-development-workflow.html