AES42 is a standard of the Audio Engineering Society( AES) from 2001 with the title: "AES Standard for Acoustics - Digital Interface for Microphones". It is about converting analog audio signals in the microphone into digital ones.
For this purpose, a new digital interface was developed, based on the AES standard AES3 from 2003: "AES Standard for Digital Audio - Digital Input-Output Interfacing - Serial Transmission Format for Two Channel linearly represented Digital Audio Data."
The standardized, serial AES3 interface is also known as the AES/ EBU interface. It operates synchronously and asynchronously over balanced cables. The power supply can be compared to the phantom power of other microphones. The phantom power, here called Digital Phantom Power( DPP), is 10 V with a maximum current draw of 250 mA. Various control signals can be sent via the phantom power, which can be used to change the microphone settings. A total of 34 commands can be transmitted via special command sets.