PSoC5LP CAN Timming

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Anonymous
Not applicable

Hello Team,

          For one of our project, we are using Cy8ckit-001 EVK Board and CY8C5868-LP035 module. We are using PSoC creator for generating API and developing firmware. While configuring CAN IP, we are confused with timing tab,  which option to select for settings(BRP/Tseg1/Tseg2/SJW) for better performance. How will these settings affect CAN performance?

           Please help us with selecting the good option which will give better CAN performance.

PSoCCreator.PNG

Thanks and Regards,

Abhishek Naik.

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1 Solution
harshadap_76
Employee
Employee
First like received

Hi Abhishek,

You can select the option that has sample point = 87.5. Sample point between 80 to 90 is always better.

You can have a look at following link for more information:

CAN Bit Time Calculation

Regards

Harshada

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5 Replies
Anonymous
Not applicable

Hello Team,

         I am waiting for your response. Please help me out with my queries.

Thanks and Regards,

Abhishek Naik.

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Anonymous
Not applicable

Hello Team,

         I am waiting for your response. Please help me out with my queries.

Thanks and Regards,

Abhishek Naik.

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harshadap_76
Employee
Employee
First like received

Hi Abhishek,

Following are the some of the best practices to choose on of the options.

1. Sample point should be close to 80 % .

2. Tseg2 and SJW should be either same or should have values close to each other.

3. Tq should be close to 25. (Better to have higher Tq value from the list).

Also these values depend on the network in which the node is placed.

As per the image the first option is better. However can you let me know what is your CAN clock?

Hope this helps.

Please feel free to update for any query.

Regards

Harshada

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Anonymous
Not applicable

Hello Harshada,

Thanks for the information.

We are using CAN interface at 250kbps speed, Clock domain is configured as below :

pastedImage_0.png

CAN Nominal freq is configured as 24MHz.

pastedImage_5.png

For CAN with speed = 250kbps, following are the timings supported :

pastedImage_3.png

As per your guidelines on choosing CAN timings i assume the highlighted option with 75%sample point and propagation delay=1750ns is a better option.

Kindly let me know if the above settings are correct?

Thanks,

Abhishek

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harshadap_76
Employee
Employee
First like received

Hi Abhishek,

You can select the option that has sample point = 87.5. Sample point between 80 to 90 is always better.

You can have a look at following link for more information:

CAN Bit Time Calculation

Regards

Harshada

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