SJA1000T/N, 112 Application Field and Working Principle

The SJA1000T/N (hereinafter referred to as “SJA1000”) is a CAN Bus microcontroller-based interface and controller developed by Philips Semiconductors. SJA1000 is a functional block, which includes a CAN protocol controller, an embedded microprocessor, a transmission buffer, and an integrated transceiver. The microprocessor core of SJA1000 has a set of self-test, transmission, and reception functions. In addition, it can also support interrupts, timeouts, filter registers, message buffers, and bus arbitration.

Overview

SJA1000 operates in a CAN Bus environment and follows the CAN 3.2 standard protocol. It can be used with other types of CAN controllers in the CAN Bus to provide a complete solution for electronic control system designs. SJA1000 supports a wide range of applications, including automotive, industrial, and medical device control systems.

Application Field

SJA1000 controllers can be used in applications such as automotive engine and body control, industrial automation control systems, and medical device control systems. The automotive engine control application can provide precise fuel control, air/fuel ratio adjustment, and feedback control functions. These functions can improve the engine response time and fuel economy, while reducing emissions. SJA1000 controllers can also be used in industrial automation control systems to provide multi-node control of machines, tools, and other factory equipment.

In medical device control applications, SJA1000 controllers can provide precise motion control within servo-systems and automated laboratory equipment. The precision timing and synchronous operation of the SJA1000 controllers allow for accurate data collection and feedback control for these types of applications.

Working Principle

SJA1000 controllers are designed to follow two communication protocols, the CAN 3.2 standard and the NXP proprietary protocol. The CAN protocol defines a message format that is universal for all CAN-compatible devices. This message format defines a data frame that contains both a header and a data portion. The header contains a message ID, which identifies the source and destination of the message, as well as the length of the data portion. The data portion contains information that is specific to the application.

The SJA1000 controller works by receiving the CAN messages, storing them in a buffer, and then transmitting them to the appropriate destination node. The controller also can send and receive messages in the NXP proprietary protocol. These messages contain commands, parameters, and data from the source node to the destination node.

The SJA1000 controller is typically integrated into the CAN Application Layer protocol stack for electronic control systems. The CAN Application Layer protocol provides an interface between the CAN Bus and external application devices such as sensors, actuators, and displays. The SJA1000 controller receives messages from the external application devices, stores them in a buffer, and then forwards them to the appropriate node on the CAN Bus.

The SJA1000 controller also can be used to provide a time-stamping service for the CAN messages. This time-stamping service is used in applications where synchronization among nodes is critical to the success of the application. For example, automotive applications such as engine control or anti-lock brakes require precise timing of the communication between the nodes to ensure accurate and reliable operation.

Conclusion

SJA1000T/N controllers are widely used in digital electronic control systems. The CAN protocol and the SJA1000 controller are designed to provide a reliable and fast communication link between nodes on a CAN Bus. The controllers provide features to help ensure the integrity of the data being transmitted, as well as for precise time-stamping of the messages. All of these features make the SJA1000 controllers an ideal solution for controlling the various components of digital electronic control systems.