How to connect arduino to intercom?

Question

Arduino

Hello! I am looking for an example of an Arduino-based device circuit, for connecting instead of / together with an
intercom handset. The device must be able to work with the intercom protocol, for example, unlock the door when receiving a call. The specific model of the intercom is not of interest. We need at least some example, on the basis of which you can understand the protocol of the intercom and collect a primitive device to work with it.
Has anyone seen an example of such a device?

Answer 1

habrahabr.ru/post/188906