Introduction

Automotive in-vehicle networking is evolving to support new features in software-defined vehicles (SDVs). As software consolidates into fewer electronic control units (ECUs) to increase scalability across vehicle platforms and streamline over-the-air (OTA) updates, a new remote-controlled edge concept optimizes wiring while enabling scalable edge-node software.

Edge nodes are specialized ECUs that handle the real-time control of specific functions, such as headlight modules for exterior lighting or control modules for door locks, windows and side mirrors. These nodes receive commands from a commander ECU (the zone controller, domain controller or central computing) throughout the in-vehicle network. Edge nodes manage local hardware control by monitoring temperature, pressure or position sensors for control-loop feedback while directly controlling mechanical actuators such as motors and solenoids through load drivers, including half bridges and high- and low-side switches. Figure 1 illustrates the difference between an edge node and commander ECUs in a zone architecture.

Remote-controlled edge architectures shift the real-time control and hardware abstraction layer (HAL) upstream to the commander ECU, which then generates low-level hardware commands for sensors and load drivers to the edge nodes. The remote-controlled edge solution bridges the higher-level network data-link layers between ECUs such as Ethernet or Controller Area Network (CAN) with low-level communication interfaces such as Serial Peripheral Interface (SPI), Inter-Integrated Circuit (I2C), universal asynchronous receiver-transmitter (UART) and general-purpose input/output (GPIO). This approach eliminates the microcontroller (MCU) as well as any software from the edge node entirely.

The remote-controlled edge scheme supports major, overarching trends around SDVs and reduces the amount of wire harnesses by centralizing software in the commander ECU, while keeping load-dependent hardware in the edge nodes close to the electromechanical actuators.

To learn more about SDVs, read the white paper, Software-Defined Vehicles Shift the Future of Automotive Electronics Into Gear.