• Locked Locked
  • Replies 9 replies
  • Subscribers 55 subscribers
  • Views 6300 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Interrupt pragma vs keyword

Tom Cauchois
Intellectual 270 points


Hi,

I'm writing interrupt service routines on a TMS570 part, and I haven't been able to find much documentation about the differences between the interrupt pragma, e.g.

#pragma INTERRUPT(func, IRQ)

void func() { }

and the interrupt keyword, e.g.

interrupt void func() { }

 

The ARM compiler's user guide doesn't talk about the difference, but the #pragma has the ability to specify which type of interrupt you're handling, which makes a difference if you're handling a data abort vs an IRQ.

Should I be using one vs the other?  Does it change with aborts vs IRQs vs FIQs?

Thanks!

Tom

  • TI__Guru**** 251490 points

    I don't think there is any difference between them.  However, I have asked other experts to comment.

    Thanks and regards,

    -George

  • in reply to George Mock
    Genius 4130 points

    All,

    I see no experts have commented further. so here is my summary.

    I use both #PRAGMA INTERRUPT and the 'interrupt' keyword (the latter for use in external tool parsing). Investigating the use of #PRAGMA INTERRUPT verses the 'interrupt' keyword I find the following:

    1. You must use #PRAGMA INTERRUPT for the exception vector ISRs type [RESET, UDEF, SWI, PABT and DABT]. If you don't you will get a completely different binary image after build that (for me) doesn't run (I get an immediate undefined instruction abort from reset).
    2. If you use #PRAGMA INTERRUPT then you don't need to use the 'interrupt' keyword.
    3. If you don't use #PRAGMA INTERRUPT but use the 'interrupt' keyword then all interrupts will be treated as IRQ. including [RESET, UDEF, SWI, PABT and DABT]. You have no way of specifying an FIQ and you will get a different binary image than if you had used #PRAGMA INTERRUPT (..., FIQ).
    This is really to be confirmed by TI, but I suggest that you must use #PRAGMA INTERRUPT not only for [RESET, UDEF, SWI, PABT and DAPT] but also IRQ and FIQ. This pragma sets attributes for the ISRs that the 'interrupt' keyword does not, for example stack allocation and the interrupt handling mechanism itself.
    I recommend that you always use #PRAGMA INTERRUPT for every ISR in your application. Use the 'interrupt' keyword in addition if required by external tool analysis (or always as it makes no difference).
    Regards, Tony
  • in reply to Tony Morrell
    TI__Guru**** 251490 points

    Tony Morrell said:
    • You must use #PRAGMA INTERRUPT for the exception vector ISRs type [RESET, UDEF, SWI, PABT and DABT]. If you don't you will get a completely different binary image after build that (for me) doesn't run (I get an immediate undefined instruction abort from reset).
    • If you use #PRAGMA INTERRUPT then you don't need to use the 'interrupt' keyword.
    • If you don't use #PRAGMA INTERRUPT but use the 'interrupt' keyword then all interrupts will be treated as IRQ. including [RESET, UDEF, SWI, PABT and DABT]. You have no way of specifying an FIQ and you will get a different binary image than if you had used #PRAGMA INTERRUPT (..., FIQ).

    I confirm that this is all correct.

    Thanks and regards,

    -George

  • in reply to George Mock
    Genius 4130 points

    I'll try and verify my answer then! Cheers, Tony

  • in reply to Tony Morrell
    Intellectual 265 points

    Hi

    I have tried the interrupt like

    #pragma INTERRUPT(c_int00,RESET)
    void c_int00(void)
    {
        main();
    }

    However, the compiler comes out with this message "#1559 Interrupt handlers must be compiled in ARM mode". I have no idea how to solve it. Do you have any idea please suggest?

    Thanks.

  • in reply to Tom Ki
    Intellectual 265 points

    Further to my post, i am using UCD31830 chips and CCSV5.5 Thanks

  • in reply to Tom Ki
    TI__Guru**** 251490 points

    Tom Ki said:
    However, the compiler comes out with this message "#1559 Interrupt handlers must be compiled in ARM mode". I have no idea how to solve it.

    Do not build with the compiler option for Thumb mode --thumb_state (or -mt for short).

    Thanks and regards,

    -George

  • in reply to George Mock
    Intellectual 265 points

    Hi George

    It work fine with my win 7 computer but not for my windows 8 computer. Is there still anything missing or the code composer V5.5 doesn't work in win 8?

    Thanks. I look forward to your prompt reply.

    Best Regards

    Tom

  • in reply to Tom Ki
    TI__Guru**** 251490 points

    Windows 8 support starts with CCS version 5.4.  Exactly what is going wrong?  You might need to attach a screen shot.

    Thanks and regards,

    -George