Spurios interrupts with new device (Revision 710) ?

doebber · ‎2007-12-20

Posted on December 20, 2007 at 10:39

doebber · ‎2011-05-17

Posted on May 17, 2011 at 09:48

Hi !

I use STR912FA (Revision 710) with KEIL development tools.

I have a problem, when using two interrupts (Timer0 and UART0) simultaneously.

Sometimes I get an spurious UART RX interrupt.

I read somthing about problems with VIC0 and VIC1 in this forum, but I thinkt this concerns only older devices. Is this problem still present in aktuell devices ?

regards

Marc

barak · ‎2011-05-17

Posted on May 17, 2011 at 09:48

Hi,

i have investigated this issue.

To help you it is neccecery to understand more about your system.

1. I need to see the IRQ_Handler.

2. are you working in low power modes?

3. are you disabling the Uart Or The timer interrupt during the regular run.

4.what do you mean by ''spurious UART RX interrupt'' what do you see?

B.R

barak · ‎2011-05-17

Posted on May 17, 2011 at 09:48

Hi,

I have never seen an issue like you are describing.

And It is hard to say without seeing the vect.s.

For example Is it implemented to support Nesting or Not.

What are the CLK’s you are using?

But there is one quick thing that I would have done differently and that is using the UART as a FIFO this is at list what I do.

Because of the high baud rate you are using it creates a lot of interrupts in the system.

I don’t know what is the clock that you are using in the system but it is always safer to have less interrupts in the system to achieve better control.

second i would check that you have given prioraty at VIC0 to the timer.

and a prioraty at at VIC1 to the UART.

B.R

doebber · ‎2011-05-17

Posted on May 17, 2011 at 09:48

Hi !

Source code -> see attached file.

I am not working in low power mode, unless the STR9 starts per default in this mode.

When I disable TIMER_IRQ it works O.K.

When I enable TIMER_IRQ, I get additional UART_IRQ (RX_Interrupt).

For example:

I receive messages with a len of 100 bytes, but sometimes I get 101 UART_IRQ.

Marc

alberto239955_stm1 · ‎2011-05-17

Posted on May 17, 2011 at 09:48

HI

I have the same problem with Tim0 and uart1

I am using the

- STR9912FA

- 12 Mhz freq.

- Timer 0 as timer tick interrupt at 40 Hz

- Uart 1 as serial communication (RX with Receive time out interrupt and TX with DMA).(see the attached uart file)

Everything works fine but some time the RX interrupt receives a byte more (6 insead of 5).

I can not see this byte coming from the RX line (oscilloscope signals are fine, i.e 5 bytes on the RX line). Actually I don´t know where this additional byte is caming from .

Is this maybe a Micro failure?

Any help is well accepted..

thank you

BR

alberto239955_stm1 · ‎2011-05-17

Posted on May 17, 2011 at 09:48

Hi

I am still here and I would like to add some more info to my previous post.

I have tried to run the Uart without the Tim0 interrupt and everything is working just fine.

As soon as I activate the Tim0 I get the error.