configuration of Clock when setting CAN's baud rate on TC27x

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I'm reading ' TC27x -c step user manual' which is composed of 5060page

according to the user manual,
in the TC27x's Multican+ module. there are two main clock. one is 'CLC clock', the other is 'CAN clock'.
CLC clock is module control clock and CAN clock is module timer clock.

I have a question.

i think CAN clock is related to Baud rate.
but is the CLC clock related to Baud rate??


I'll show you an example.
if CAN clock is 10 Mhz . and don't use prescaling
And Bit timing is 10 tq.
( NBTRx=0x3449 )
In this situation, I think the baudrate will be 1Mbits/s
but does the CLC clock affect the baud rate??
3 Replies
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IN the user manual
there is a Table 22-4 'Miminum Operation Frequncies required 500MBaud'
and an equation. Baudrate max = [ (8 X T can) + (8 X T clc)+(4X No of active CAN node) ]
but i can not understand the table and equation
please help me..
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Hello Persnet3,

I got the same question. Do you already have found an answer?

I'm trying to set the baudrate with the Tasking SW platform. Currently, strange unexpected things happen (baudrate req. =1e6 Hz; baudrate measured ~ 1.8 MHz).

I'll need to do some investigations on this (like you did).

Best regards
TomBom
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Hello Persnet3,

I did some further investigations and found a white paper from Vector, which gives some basic explanaition of the bit timing and how to set ist up.
I like it very much. The document is called:

Basic CAN Bit Timing, Version 2.0, Application Note AN-AND-1-106

You also get some hints on how to debug your application on the physical layer!

Additionally, you might look at: http://www.bittiming.can-wiki.info/

Furthermore, IFX published a document for the XMC- controller series, discussing some details of the Multican-unit: Infineon-MultiCAN-XMC4000-AP32300-AN-v01_00-EN.pdf

These documents and the Aurix user manual will help you to better understand setting up the timing registers for a proper Can bus operation.

Best regards
TomBom
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