It is difficult to create a common platform to support completely different applications. In this presentation we will examine heterogenous platforms that tightly couple microcontrollers with FPGAs to increase computing capacity, provide flexible interface capabilities or use other features. We will examine how to setup a link between Coldfire and Spartan 6 devices through mini-flex bus. Bus differences for Kinetis devices will be noted, that shows the advantages of these newer devices and some application examples will be shown.