Header CRC in Freescale example for MCU : 16-bit MC9S12XF512MLM

Discussion created by Richard DE MIRANDA on Mar 27, 2012
Latest reply on Mar 28, 2012 by Richard DE MIRANDA

Hi everybody,


I have some problem ton calculte the header CRC from a frame. For exemple, in the example freescale, the header CRC for a transmit frame SLOT09 is : 0x03FC.


When i calculate it, i find 0x2d7.


Caracteristic of the frame :

Header CRC = 0x03FC

Sync frame indicator : 1

Startup frame indicator : 1

ID : 9

Payload length : 16


So i have my frame is equal to that : 1100 0000 0100 1001 0000

I compute there with the polynomial sequence define in the Flexray criteria : 1011 1000 0101 (x^11 + x^9 + x^8 + x^7 +x^2 +1)


Why I don't find the same Header CRC?


Thank you in advance,


Best regards,