An improved vehicle communications interface (VCI) is both economical and readily adaptable for running new software. The improved VCI includes a server coupled to a bank of processors. The server can communicate with a host, and the processors can communicate with different vehicle networks. Each processor includes a state machine and a media access controller for a particular vehicle network. The state machine identifies incoming messages that require real time responses and provides the requisite responses directly back to the network, without involvement of the server. Real time requirements of the server are thus relieved, allowing the server to run a non-real time, mainstream operating system for which new product software is readily available.