ST AEK-COM-10BASET User Manual

How to use the AEK-COM-10BASET two-channel 10BASE-T1S packet converter
Introduction
New megatrends in the automotive industry, such as personalization, electrification, autonomy, and full connectivity are moving
in-vehicle networks away from domain-based solutions, gravitating towards new zonal architectures.
Unlike domain-based architectures, zonal-based architectures exploit connectivity based on physical location rather than
function, significantly reducing the number of electronic control units (ECUs) in vehicles and the cabling harness weight. As
existing legacy connectivity technologies (such as FlexRay and CAN) have exceeded the maximum acceptable latency, Time
Sensitive Networks (TSN) based on Ethernet connectivity represent the best alternative to fully leverage the advantages of this
new architecture, all the way to edge sensors and actuators.
As cars become more autonomous and interconnected, the automotive field is becoming increasingly software-defined, making
in-vehicle electronics grow in volume and complexity to support the goal for autonomous driving. In this context, 10BASE-T1S
automotive Ethernet enhances in-vehicle network (IVN) architectures by connecting sensors, car body and infotainment engine
control units (ECUs).
10BASE-T1S protocol supports half-duplex and full-duplex communication, allowing either a point-to-point direct connection
between two nodes, or use of a multidrop topology with up-to-eight nodes connected on a single 25 m bus segment.
10BASE-T1S reduces total system cost by using a single pair of wires and a multidrop bus architecture. It also increases system
scalability since several nodes can operate on the same bus line with high data throughput. Thanks to the multidrop topology,
multiple heterogeneous end points can be connected on a single cable in zonal architectures (for example, the door zone, the
window lifter, the mirror control, speakers, car locks, ultrasonic sensors, ambient light sensor, and indicator light). This bus
implementation provides an optimized Bill –of-Material (BOM) only requiring a single Ethernet PHY in each node, removing the
need for a switch or star topology implementation associated with typical Ethernet technologies. Furthermore, the physical layer
collision avoidance (PLCA) technology minimizes dead time and avoids collisions. PLCA allows only the PHY device that owns
the transmit opportunity to send data. PHY devices with no data to transmit will be given minimal opportunity to send data,
increasing the bandwidth of your network.
Our AEK-COM-10BASET evaluation board perfectly meets the requirements of these new automotive megatrends, representing
a powerful tool to explore various vehicle network architectures. By combining 10BASE-T1S automotive Ethernet protocol and
other legacy automotive interfaces (CAN, CAN-FD, and SPI), it allows using a single software framework throughout the vehicle
from the lowest to the highest speed ranges.
This board merges the innovations brought by the new 10BASE-T1S specification with the high-performance dual-core
SPC58EC80E5 Chorus family microcontroller.
The AEK-COM-10BASET essentially acts as a gateway to interconnect heterogeneous communication systems, allowing a
vehicle zone sensor/actuator to receive messages in the 10BASE-T1S protocol format even if the zone components are not
able to communicate via Ethernet.
The board features a PHY-MAC transceiver, which communicates with the MCU via SPI, and a PHY only transceiver requiring
an Ethernet MAC to run in the MCU.
In our board, these transceivers support only half-duplex communication. Both are connected to the MCU, one using the MII
port while the other using a SPI channel. The firmware embedded in the board can manage a software-implemented Ethernet
MAC and runs under FreeRTOS operating system.
The board is very flexible, allowing several gateway packet conversions to and from 10BASE-T1S, CAN-FD, and SPI. The
function can be limited to gateway purposes or can also be extended to decode actuation commands and forward them to
several daughter boards via the available ports. For example, a Power Distribution Unit (PDU) daughter board containing E-
fuses can be controlled via CAN or SPI by decoding 10BASE-T1S frames.
The board features a pre-loaded demo example. This example involves a loopback test among the two 10BASE-T1S channels
and two CAN channels. The message is sent via CAN sender port, packed in 10BASE-T1S sent to the other 10BASE-T1S
channel, and finally unpacked for a CAN receiving port.
The AEK-COM-10BASET also hosts an OpenOCD debugger/programmer, MCU peripheral connectors, wakeup and reset
buttons.
The MCU ADC reference voltage is provided by a stable linear voltage regulator (LDO) embedded in the
UM3460 - Rev 1 - December 2024
For further information contact your local STMicroelectronics sales office.
UM3460
User manual
evaluation board
L5963 IC.
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