CAN Bus Port Switching for Daisy-Chain Auto-Addressing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing communication buses operating under the CAN FD Light protocol lack an auto-addressing feature for daisy-chain topologies, necessitating manual assignment of individual addresses to devices, which is logistically challenging and inefficient.
Innovation Solution
A differential bus communication system with a CAN protocol controller and transceiver circuits that enable auto-addressing by disabling and enabling communication ports using control signals, combined with logic gates to manage signal flow, allowing sequential assignment of unique addresses to devices in a daisy-chain topology.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If manual address assignment is used in CAN FD Light protocol, then device addressing is possible, but logistical effort and complexity increase significantly
Solution Approach 1:
The system implements self-service through automatic address assignment where devices autonomously configure their own addresses without manual intervention. The master device automatically assigns addresses to slave devices in daisy-chain topology, eliminating the need for manual configuration and reducing both logistical effort and time consumption.
Solution Approach 2:
The system performs preliminary action by pre-configuring address assignment logic within the master device before actual communication begins. The address assignment mechanism is prepared in advance and executed automatically during system initialization, avoiding the need for manual address configuration at deployment time.
2Extent of automation
If control signals are used to disable/enable communication ports, then auto-addressing is enabled, but device complexity increases
Solution Approach 1:
The control signal mechanism serves multiple functions: it enables automatic address assignment during initialization, manages communication port states for daisy-chain topology, and coordinates between master and slave devices. This multi-functionality reduces the need for separate dedicated components, thereby limiting the increase in device complexity while achieving high automation.
3Adaptability or versatility
If daisy-chain topology is used, then network scalability is improved, but signal integrity and electromagnetic interference increase
Solution Approach 1:
The system segments the communication network into distinct master and slave devices with defined roles. The master device manages address assignment and communication coordination, while slave devices have standardized interfaces. This segmentation allows the daisy-chain topology to scale efficiently while maintaining signal integrity through controlled device interfaces and communication protocols.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
An electronic device (42) includes a CAN protocol controller (320), a first communication port (326d) configured for coupling to a first segment of a differential bus to exchange CAN signals therewith, and a second communication port (326u) configured for coupling to a second segment of the differential bus to exchange CAN signals therewith. A first CAN transceiver circuit (324d) is coupled to the CAN protocol controller (320) and is configured to receive a first CAN transmission signal (TXDd) therefrom and to transmit a first CAN reception signal (RXDd) thereto. The first CAN transceiver circuit (324d) is coupled to the first communication port (326d) to drive (50) a differential voltage at the first segment of the differential bus as a function of the first CAN transmission signal (TXDd) and to sense (56) a differential voltage at the first segment of the differential bus to produce the first CAN reception signal (RXDd). The second communication port (326u) is enabled in response to a control signal (DISABLE) being de-asserted and disabled in response to the control signal (DISABLE) being asserted. The CAN signals are passed between the first communication port (326d) and the second communication port (326u) in response to the control signal (DISABLE) being de-asserted, and the CAN signals are not passed between the first communication port (326d) and the second communication port (326u) in response to the control signal (DISABLE) being asserted.