A Novel Solution to the Synchronization Problem of CAN
Ms. Shilpa Mayannavar , Prof. Ashwini Desai, Dr. Uday Wali
One of the main problems in synchronous digital system design is synchronization of different clocks in the system. Obviously, this problem is always present in CAN bus related equipment. The problem is more acute in CAN compared to other high speed serial protocols like I2C and SPI. Speed of communication is pre-negotiated but synchronization is provided by the data frame. No separate clock line is provided. We have implemented a CAN transceiver that can automatically detect the speed and synchronization from the data frame. We have approached the problem in two distinct steps. First step is to identify the baud rate. In the following step, which is applied to every frame independently, the sampling time is adjusted with respected to the frame clock. The method also adjusts the sampling rate to reduce the number of samples required to sense the input signal. We also use a novel bit-central-sampling scheme to increase the reliability of data reading.
CAN (Controller Area Network), Frame synchronization, I2C (Inter Integrated Circuits), SPI (Serial Peripheral Interface)
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 Design of CAN transmitter with an I2C interface, Anupama B and Uday Wali, International Journal of Computer Applications, Vol. 46, no. 21, ISBN 973-93-80868-65-5
 High speed CAN Transceiver, Microchip, available from web link http://ww1.microchip.com/downloads/en/DeviceDoc/21667E.pdf
 LPC2119/2129/2194/2292/2294 User Manual, NXP Semiconductor, http://www.nxp.com/acrobat_download/usermanuals/UM_LPC21XX _LPC22XX_2.pdf
 CAN specification 2.0, Rober Bosch, 1991, http://www.semiconductors.bosch.de/pdf/can2spec.pdf
[Ms. Shilpa Mayannavar , Prof. Ashwini Desai, Dr. Uday Wali (2014) A Novel Solution to the Synchronization Problem of CAN IJIRCST Vol-2 Issue-4 Page No-69-72] (ISSN 2347 - 5552). www.ijircst.org
Ms. Shilpa Mayannavar
M.Tech. 4th semester student (VLSI Design and Embedded System), KLE DR MSS CET, Belgaum, India, 8431478910., (e-mail: firstname.lastname@example.org).