CAN

Features articles on the CAN Bus. CAN or Controller Area Network is normally used in Automotive systems, but are finding its way into other areas such as PV Solar Inverters, Energy Storage Systems (ESS) and Telecommunication Power Supplies.

Electric Vehicles

IEC61851 / J1772 Electric Vehicle Charge Controller

December 27, 2021 Craig Peacock 12

This device acts as the vehicle when connected to an EVSE (Electric Vehicle Supply Equipment) and negotiates the supply of power. It can be used in EV (Electric Vehicle) conversions, or in applications where you want to obtain power from public charging infrastructure – i.e., battery trailers to replace dirty and noisy generators, electric watercraft etc. Both hardware and firmware is provided as open source. The provided firmware will allow the EVCC to successfully request power and obtain the maximum obtainable current. Boiler plate code is available for the CAN interface and some firmware development would be expected to interface …

CAN - Controller Area Network

Review: Huawei R4850G2 Power Supply 53.5VDC, 3kW with CAN

December 27, 2020 Craig Peacock 66

The Huawei R4850G2 is a very capable 48V Telecommunications grade power supply available brand-new at cheap surplus prices (normally under $100 USD). Rated at 3000W, it can deliver a considerable 56.1A when powered from a suitable 200-240V rated AC source. The CAN2.0B interface allows for online monitoring and/or adjustment of the output voltage and current. Given the power supply is a Telecoms spare part (most likely for a Huawei mobile phone Base Terminal Station), a surprisable amount of official documentation exists on the hardware from the manufacturer: But when it comes to the CAN communications protocol and operation, the best …

CAN - Controller Area Network

SWCAN Single Wire CAN Transceiver Breakout Board

June 19, 2020 Craig Peacock 17

Single Wire CAN (SAE J2411) is commonly used in cost-sensitive Automotive applications where speed and cable length is not as onerous. It is also useful in applications were a traditional CAN differential pair is physically not possible. For example, on Type 2 Mennekes connectors used for Electric Vehicle (EV) charging, the communication between the supply equipment and the vehicle is performed via a PWM signal on a single Control Pilot (CP) pin in respect to earth. Tesla has used SWCAN to digitally communicate over this single pin. Various SWCAN drivers are available and generally share the same compatible pinout (SO8 and …

CAN - Controller Area Network

Adding CAN to the BeagleBone (Black)

February 10, 2020 Craig Peacock 5

The CAN bus (Controller Area Network) was originally designed by Bosch for the automotive market to connect ECUs (Engine/Electronic Control Units) together. Today, this robust communications bus is commonly found, not only in vehicles, but also on the factory floor in automation (e.g. CANOpen) and other applications such as PV solar inverter/battery Energy Storage Systems (ESS). The Sitara AM335x MCU found on the BeagleBone includes two CAN 2.0 controllers (DCAN) using IP modules from Bosch. The BeagleBone Black PCB, however, doesn’t include any CAN bus transceivers and these must be added externally. CAN Transceiver Wiring The BeagleBone Black has two DCAN ports: DCAN0 …

CAN - Controller Area Network

Example C SocketCAN Code

January 31, 2020 Craig Peacock 7

Writing user space C code to talk to CAN devices via the Linux SocketCAN interface is relatively simple and efficient. SocketCAN uses the Berkeley socket API and hence is very similar to communicating with other network socket devices. Below is a simple guide to get you started reading, writing and filtering CAN packets. Official documentation for the SocketCAN interface can be found at: https://www.kernel.org/doc/Documentation/networking/can.txt Complete code for the following examples can be found at the following GitHub repository: https://github.com/craigpeacock/CAN-Examples These examples do not include make files. To build a source file, you can simply use gcc. For example, to build …

CAN - Controller Area Network

Adding CAN to the Raspberry PI

January 17, 2020 Craig Peacock 23

The CAN bus (Controller Area Network) was originally designed by Bosch for the automotive market to connect ECUs (Engine/Electronic Control Units) together. Today, this robust communications bus is commonly found, not only in vehicles, but also on the factory floor in automation (e.g. CANOpen) and other applications such as PV solar inverter/battery Energy Storage Systems (ESS). The Raspberry PI doesn’t natively support CAN. The Broadcom SoCs (System on a Chip) used by the Raspberry PI doesn’t include a CAN controller. The Linux kernel supports CAN and includes SocketCAN drivers for the Microchip MCP2515 Stand-alone CAN Controller with SPI Interface. Various …