CCS RTOS problem please help me

[Marco_Arg]

I have the following problem, I am trying to use RTOS to receive characters via software uart and it works fine, simultaneously I use a simple task to toggle a LED every 0.5 seconds, there is where I have a problem. When I set the LED task RATE higher than 30ms the LED task works erratically, but if I set the RATE to 30 ms it works perfectly, of course the led toggle too fast.

What I am doing wrong?

Thanks



Here is the code: I am using CCS V4


#include <18F452.h>
#fuses H4,NOWDT,NOPROTECT,NOBROWNOUT,NOLVP
#use delay(clock=40000000)
#use RS232(baud=38400,xmit=PIN_C1,rcv=PIN_C2,bits=8,parity=N,stream=debug,errors)

#use rtos(timer=0, minor_cycle=250us )

#define LED pin_c4

// Variables
#zero_ram
int8 buffer_232[20];

#task (rate=250us) // check for incoming bytes and when buffer reachs 8, send them to PC
void get_rs232(void){
static int8 rcvd=0;

while (!kbhit(debug))
rtos_yield();

buffer_232[rcvd]=getc(debug);
rcvd++;

if (rcvd >=8){
fprintf(debug,"%s",buffer_232);
rcvd=0;
}
}

#task (rate=500ms) // every 0.5 sec toggle LED
void toogle_led(void){
static int1 aux=0;
aux=!aux;
if (aux==1)
output_high(led);
else
output_low(led);
}

void main(void){

setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);

disable_interrupts(GLOBAL);
setup_psp(PSP_DISABLED);
setup_spi(FALSE);
setup_timer_0 (RTCC_DIV_2|RTCC_INTERNAL|RTCC_8_BIT);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);

set_tris_a ( 0b00001000 );
set_tris_b ( 0b11111111 ); //All Inputs
set_tris_c ( 0b10000010 ); //All Outputs
set_tris_d ( 0b00000000 ); //All Outputs
set_tris_e ( 0b00000111 ); //All Inputs

output_high(LED);

rtos_run(); // Run RTOS Tasks
}

[Guest]

I have the following problem, I am trying to use RTOS to receive
characters via software uart and it works fine, simultaneously I use a
simple task to toggle a LED every 0.5 seconds, there is where I have a
problem. When I set the LED task RATE higher than 30ms the LED task
works erratically, but if I set the RATE to 30 ms it works perfectly, of
course the led toggle too fast.

What I am doing wrong?

Thanks


PD: sorry I didnt know how to post code now it is corrected.

I contiue testing the code and when I change #USE RTOS minor_cycle
value to something really small like 10us or less, all the task RATES must
be no higher than 2 ms or else the code will fail, I dunno why.

[bwhiten]

I believe your settings for Timer0 may not allow for a 500ms time out at your clock setting of 40MHz.