SPRAC35 March 2016 F28M35E20B , F28M35E20B , F28M35H22C , F28M35H22C , F28M35H52C , F28M35H52C , F28M35H52C-Q1 , F28M35H52C-Q1 , F28M35M22C , F28M35M22C , F28M35M52C , F28M35M52C , F28M36H33B2 , F28M36H33B2 , F28M36H53B2 , F28M36H53B2 , F28M36P53C2 , F28M36P53C2 , F28M36P63C2 , F28M36P63C2 , TMS320F2800132 , TMS320F2800132 , TMS320F2800133 , TMS320F2800133 , TMS320F2800135 , TMS320F2800135 , TMS320F2800137 , TMS320F2800137 , TMS320F2800152-Q1 , TMS320F2800152-Q1 , TMS320F2800153-Q1 , TMS320F2800153-Q1 , TMS320F2800154-Q1 , TMS320F2800154-Q1 , TMS320F2800155 , TMS320F2800155 , TMS320F2800155-Q1 , TMS320F2800155-Q1 , TMS320F2800156-Q1 , TMS320F2800156-Q1 , TMS320F2800157 , TMS320F2800157 , TMS320F2800157-Q1 , TMS320F2800157-Q1 , TMS320F280021 , TMS320F280021 , TMS320F280021-Q1 , TMS320F280021-Q1 , TMS320F280023 , TMS320F280023 , TMS320F280023-Q1 , TMS320F280023-Q1 , TMS320F280023C , TMS320F280023C , TMS320F280025 , TMS320F280025 , TMS320F280025-Q1 , TMS320F280025-Q1 , TMS320F280025C , TMS320F280025C , TMS320F280025C-Q1 , TMS320F280025C-Q1 , TMS320F280040-Q1 , TMS320F280040-Q1 , TMS320F280040C-Q1 , TMS320F280040C-Q1 , TMS320F280041 , TMS320F280041 , TMS320F280041-Q1 , TMS320F280041-Q1 , TMS320F280041C , TMS320F280041C , TMS320F280041C-Q1 , TMS320F280041C-Q1 , TMS320F280045 , TMS320F280045 , TMS320F280048-Q1 , TMS320F280048-Q1 , TMS320F280048C-Q1 , TMS320F280048C-Q1 , TMS320F280049 , TMS320F280049 , TMS320F280049-Q1 , TMS320F280049-Q1 , TMS320F280049C , TMS320F280049C , TMS320F280049C-Q1 , TMS320F280049C-Q1 , TMS320F2801 , TMS320F2801 , TMS320F2801-Q1 , TMS320F2801-Q1 , TMS320F28015 , TMS320F28015 , TMS320F28016 , TMS320F28016 , TMS320F28016-Q1 , TMS320F28016-Q1 , TMS320F2802 , TMS320F2802 , TMS320F2802-Q1 , TMS320F2802-Q1 , TMS320F28030 , TMS320F28030 , TMS320F28030-Q1 , TMS320F28030-Q1 , TMS320F28031 , TMS320F28031 , TMS320F28031-Q1 , TMS320F28031-Q1 , TMS320F28032 , TMS320F28032 , TMS320F28032-Q1 , TMS320F28032-Q1 , TMS320F28033 , TMS320F28033 , TMS320F28033-Q1 , TMS320F28033-Q1 , TMS320F28034 , TMS320F28034 , TMS320F28034-Q1 , TMS320F28034-Q1 , TMS320F28035 , TMS320F28035 , TMS320F28035-EP , TMS320F28035-EP , TMS320F28035-Q1 , TMS320F28035-Q1 , TMS320F28044 , TMS320F28044 , TMS320F28050 , TMS320F28050 , TMS320F28051 , TMS320F28051 , TMS320F28052 , TMS320F28052 , TMS320F28052-Q1 , TMS320F28052-Q1 , TMS320F28052F , TMS320F28052F , TMS320F28052F-Q1 , TMS320F28052F-Q1 , TMS320F28052M , TMS320F28052M , TMS320F28052M-Q1 , TMS320F28052M-Q1 , TMS320F28053 , TMS320F28053 , TMS320F28054 , TMS320F28054 , TMS320F28054-Q1 , TMS320F28054-Q1 , TMS320F28054F , TMS320F28054F , TMS320F28054F-Q1 , TMS320F28054F-Q1 , TMS320F28054M , TMS320F28054M , TMS320F28054M-Q1 , TMS320F28054M-Q1 , TMS320F28055 , TMS320F28055 , TMS320F2806 , TMS320F2806 , TMS320F2806-Q1 , TMS320F2806-Q1 , TMS320F28062 , TMS320F28062 , TMS320F28062-Q1 , TMS320F28062-Q1 , TMS320F28062F , TMS320F28062F , TMS320F28062F-Q1 , TMS320F28062F-Q1 , TMS320F28063 , TMS320F28063 , TMS320F28064 , TMS320F28064 , TMS320F28065 , TMS320F28065 , TMS320F28066 , TMS320F28066 , TMS320F28066-Q1 , TMS320F28066-Q1 , TMS320F28067 , TMS320F28067 , TMS320F28067-Q1 , TMS320F28067-Q1 , TMS320F28068F , TMS320F28068F , TMS320F28068M , TMS320F28068M , TMS320F28069 , TMS320F28069 , TMS320F28069-Q1 , TMS320F28069-Q1 , TMS320F28069F , TMS320F28069F , TMS320F28069F-Q1 , TMS320F28069F-Q1 , TMS320F28069M , TMS320F28069M , TMS320F28069M-Q1 , TMS320F28069M-Q1 , TMS320F28075 , TMS320F28075 , TMS320F28075-Q1 , TMS320F28075-Q1 , TMS320F2808 , TMS320F2808 , TMS320F2808-Q1 , TMS320F2808-Q1 , TMS320F2809 , TMS320F2809 , TMS320F2810 , TMS320F2810 , TMS320F2810-Q1 , TMS320F2810-Q1 , TMS320F2811 , TMS320F2811 , TMS320F2811-Q1 , TMS320F2811-Q1 , TMS320F2812 , TMS320F2812 , TMS320F2812-Q1 , TMS320F2812-Q1 , TMS320F28232 , TMS320F28232 , TMS320F28232-Q1 , TMS320F28232-Q1 , TMS320F28234 , TMS320F28234 , TMS320F28234-Q1 , TMS320F28234-Q1 , TMS320F28235 , TMS320F28235 , TMS320F28235-Q1 , TMS320F28235-Q1 , TMS320F28332 , TMS320F28332 , TMS320F28333 , TMS320F28333 , TMS320F28334 , TMS320F28334 , TMS320F28335 , TMS320F28335 , TMS320F28335-Q1 , TMS320F28335-Q1 , TMS320F28374D , TMS320F28374D , TMS320F28374S , TMS320F28374S , TMS320F28375D , TMS320F28375D , TMS320F28375S , TMS320F28375S , TMS320F28375S-Q1 , TMS320F28375S-Q1 , TMS320F28376D , TMS320F28376D , TMS320F28376S , TMS320F28376S , TMS320F28377D , TMS320F28377D , TMS320F28377D-EP , TMS320F28377D-EP , TMS320F28377D-Q1 , TMS320F28377D-Q1 , TMS320F28377S , TMS320F28377S , TMS320F28377S-Q1 , TMS320F28377S-Q1 , TMS320F28379D , TMS320F28379D , TMS320F28379D-Q1 , TMS320F28379D-Q1 , TMS320F28379S , TMS320F28379S
Controller Area Network (CAN) nodes use user-specified timing parameters to sample the asynchronous bitstream and recover the clock. These parameters are typically based on the frequency of the available reference oscillator. There may be several options available for a given frequency, and some of them will allow a looser oscillator tolerance than others. This application report details the creation of a bit timing calculator to maximize the oscillator tolerance for the CAN modules on TI microcontrollers.
Project collateral discussed in this application report can be downloaded from the following URL: http://www.ti.com/lit/zip/sprac35.
TMS320C2000 is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
Calculation of the bit timing parameters requires at least three inputs:
The propagation delay comes from two main sources: the speed of electromagnetic propagation along the bus wiring and extra delay due to transceivers, isolation, or other interface circuitry.
A bit timing calculator must provide at least five outputs:
The calculator described in this document also outputs the number of time quanta per bit, the oscillator tolerance, the sampling point, and timing register values for the eCAN and D_CAN modules used on the TMS320C2000™ series of microcontrollers.