topic RTI interrupt with external clock in CodeWarrior for MCU

RTI interrupt with external clock

Diana — Mon, 11 May 2009 18:11:55 GMT

Hello,

I need to create a time interruption to send some data, and I have choose RTI interrupt, but it don't run.

The interruptions is:

/////////////////////////////

__interrupt 25 void Vrti_isr(void)

{

SRTISC_RTIACK=1;

tiempo=1; // when this variables is 1 I send the dates.

}

////////////////////

In the main funcion I inicialize de interrupt with:

SRTISC=0x77; // I use external clock of 62,5kHz because we are on run mode

EnableInterrupts;

What is wrong?

Is there any easy way to make a break in time?

Re: RTI interrupt with external clock

peg — Mon, 11 May 2009 19:31:46 GMT

Hello Diana,

You need to tell us what part you are using.

With some devices the RTI does not function in all clock modes.

Re: RTI interrupt with external clock

Diana — Mon, 11 May 2009 20:29:09 GMT

Hello,

I am using 13192sard, with MC9S08GT60 44pins microcontroller. The frecuency of its external clock is 62.5kHz. I need send information to the PC every minute and had thought with a interrupt RTI.

Re: RTI interrupt with external clock

peg — Tue, 12 May 2009 05:27:55 GMT

Hi Diana,

It seems setup correctly to me!

A couple of things though:

I thought the SARD's MPU used the clock output from the radio device for its clock (16MHz?)

If you are only going to set a flag in the ISR for later use you may as well not enable interrupts and simply test the RTIF bit in SRTISC. (still need to ACK it)

Re: RTI interrupt with external clock

Diana — Thu, 14 May 2009 14:28:46 GMT

Hi Pej,

I had found this frecuency in the next file.

MC13192_EVBRM.pdf

Message Edited by t.dowe on 2009-10-22 09:14 AM

Re: RTI interrupt with external clock

peg — Thu, 14 May 2009 14:39:05 GMT

Hello Diana,

You mentioned SARD before now you are talking EVB!

It does say 62.5kHz here but the output of the radio is programmable so you would need to check. You could also test it at TP6.

It should still work though.