Reasons for Dealys in interrupt in KEA-128

[vigneshbalaji]

Hi,

    I want to know what are the things which will delay an interrupt in KEA-128?

Does using printf will delay the interrupt?

Please give me a detailed Explanation on it.

[kerryzhou]

Hi VIGENESH BALAJI,

    If you have the other interrupt which have the higher priority, then it will cause the lower priority interrupt be delay.

    About the printf, actually it is using the UART, if your UART have the higher interrupt priority, it may cause the interrupt which have lower priority than UART Interrupt delay. But if the UART never use the interrupt, it won't cause other interrupt be delay.

  Wish it helps you!

If you still have question, please contact me!

Have a great day,
Jingjing

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[vigneshbalaji]

Hi Jing,

            I want to know the length the hardware interrupt buffer?.Since CAN interrupt is having the lowest priority and UART has higher priority than that.If suppose in a sequence First UART message then another CAN message then Second UART message comes.Will the Second UART message be served first or the CAN message?

I also want to know the length of interrupt queue?Please provide me Screenshots from your source.

[kerryzhou]

Hi VIGNESH BALAJI,

      The KEA128 supports four priority levels for interrupts.

    The default priority, CAN have the lowest priority, but you can use the ARM priority register to set the CAN as the higher priority than the UART.

    You can use thevoid NVIC_SetPriority(IRQn_Type IRQn, uint32_t priority) function to configure the MSCAN priority.

    Now answer your questions.

    1. If the second UART message is coming later the CAN message, of course the MSCAN message will be served at first.

      But if the seconed UART and the MSCAN interrupt happens in the same time, the UART interrupt will be served at first.

    2. What the length of the interrupt queue?  Just the server time? it is determined by the interrupt service function.

        If you want to know the interrupt priority levels, it is 4, our interrupt is the Nested Vectored Interrupt Controller, 4 priority levels.

Wish it helps you!

If you still have question,please contact me!

Have a great day,
Jingjing

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------