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CANopen and J1939 co-processors, free eval kits at int. CAN Conference March 5th/6th

February 9th, 2012 Comments off

On March 5th, ESAcademy will conduct the following classes at the iCC together with NXP Semiconductors:

08:30 to 09:30 Everything CAN and NXP CAN Controller Intro
A 30 year old technology, here to stay for another 30 years

An overview of the almost 30 year old CAN technology, where it came from and where it goes. CAN is used in many new electronic designs, also thanks to continuous advancements in CAN controller technology. Comparison of various CAN controller technologies.

09:45 to 10:30 CANopen Essence
New to CANopen? Learn the key features in just 45 Minutes

With its 4000+ pages the CANopen drafts and standards are overwhelming to newcomers. Join this class to get an overview of the common technical key features that make CANopen work.

11:30 to 13:00  Introduction to NXP CAN microcontrollers and Co-Processors
CAN controllers, CANopen Co-Processor, J1939 Co-Processor

Specialties of NXP CAN controllers and how an LPC11C24 can be used as a communication Co-Processor. Using the LPC11C24 with integrated CAN transceivers to implement a Co-Processor to implement and handle a higher-layer protocol, offloading this task from a host processor system. The host system communicates with the gateway via
UART, I2C or SPI.

Participants may qualify for a free NXP Evaluation Kit (must be present to qualify, 50 kits available).

For more information about the international CAN conference visit: www.can-cia.org

Categories: CAN, CANopen Tags: ,

CAN bit rates beyond 1MBps

May 16th, 2011 Comments off

For many years the maximum bit rate of CAN (Controller Area Network) has been 1Mbps. Not only was it a maximum for the bit rate, it also resulted in a “touchy” physical layout: cable length restrictions were as low as 30m.

The limits of speed vs. cable length comes from the requirement, that in CAN a bit needs to be stable on the entire bus, before the next bit may start. Some bits can be over-written, a feature which is used for arbitration, acknowledgments and error handling.

Bosch, the inventor of CAN, now introduced a white paper “CAN with Flexible Data-Rate” showing how a higher data rate can be achieved. The main suggested feature here is to allow switching between a low (backward compatible) bit rate and a much higher bit rate within a single message.

In short, a single CAN message consist of control data at the beginning and the end of a message with the data field “in the middle”. The core idea is to use the lower bit rate for the control data and the higher bit rate for the data field only. In addition the maximum data field size is increased from previously 8 bytes to now 64 bytes.

If the higher bit rate is 8 times higher than that of the base rate it would be possible to achieve an 8 times higher data-throughput WITHOUT changing the real-time behavior.

For more info, see the white paper at:
www.semiconductors.bosch.de/media/pdf/canliteratur/can_fd.pdf

Categories: CAN Tags: ,