Recently, the introduction of Internet of Things (IoT) concept has promoted new applications in the agricultural domain, powering the development of Agriculture 4.0. One of the major issues is the incompatibility of devices and protocols. In this work, we address the interoperability between Electronic Control Units (ECUs) on the agricultural machinery by means of developing of a Network Interconnection Units (NIU). The NIU interconnects two heterogeneous physical networks, one based on CAN 2.0 B standard, and the other one based on IEEE 802.15.4 standard by means of the ISO 11783 protocol implementation with the purpose of extending this last protocol for wireless applications. The proposed NIU was implemented using a general purpose development board in correspondence with the rapid prototyping and constrained devices concepts of IoT. NIU performances were evaluated and analyzed in terms of ISO 11783 network requirements.