topic Re: Changing the MQX tick rate in MQX Software Solutions

Changing the MQX tick rate

RWey — Sat, 21 Apr 2012 04:24:30 GMT

This is probably a simple question, but being new to MQX please find it in your hearts to forgive me.

I'm using MQX 3.8 along with Processor Expert and I'm having trouble changing the MQX tick rate. It's easy enough to call the _time_set_ticks_per_second( 1000 ) function, and while querying with the associated "get" function shows the change, doing some timing tests shows the actual time is still at the default 200 tps.

If you look at the kernel function definition, the comment mentions: "THIS MUST AGREE WITH THE ACTUAL INTERRUPT PERIOD...", so the question is, how does one change the "actual interrupt period" so it agrees with the new 1mS tick rate ?

Thanks.

Re: Changing the MQX tick rate

MarkP_ — Sun, 22 Apr 2012 19:41:12 GMT

In twrk60n512.h is default:

/* ** The clock tick rate */

#ifndef BSP_ALARM_FREQUENCY

#define BSP_ALARM_FREQUENCY (200)

#endif

Add own definition into user_config.h:

#define BSP_ALARM_FREQUENCY 1000 /* 1 ms tick */

~Mark

Re: Changing the MQX tick rate

RWey — Tue, 24 Apr 2012 02:45:12 GMT

Thanks Mark, that seems to make sense.

I'm wondering, however, why the tick rate is refered to as "tick rate" everywhere else, yet this critical definitions names it "

BSP_ALARM_FREQUENCY" ?

Am I missing something.

Re: Changing the MQX tick rate

barbercolman — Thu, 12 Jul 2012 22:10:10 GMT

I am planning on changing the tick from 5 ms to 1 ms on a k60n512 project. Only one very short task will run every ms. Does anyone have experience to say if this will be a problem?

Thanks

Re: Changing the MQX tick rate

c0170 — Fri, 13 Jul 2012 14:53:09 GMT

Hi barber colman,

can you be more explicit what's your use case?

Regards,

MartinK