help for pic micro controller code 16f690

[samuel.sam77]

hi am beginner of pic programmer i need a code for pwm smooth start for my smbs ..here i am using pic 16f690 .i enabled eccp pwm ..i here i show the code is working halfbridge mode

so i need when i switch on the pulse to start from 0 to loaded duty cycle value ..this is my code using ccs c complier

#USE DELAY (CLOCK=8000000)
#byte PWM1CON=0x1C
#byte Eccpas = 0x1D
#define CCP_SHUTDOWN_MODE (CCP_SHUTDOWN_ON_INT0 | \
CCP_SHUTDOWN_AC_L | \
CCP_SHUTDOWN_BD_L | \
CCP_SHUTDOWN_RESTART)
#byte ccp1con=0x17
void main()
{
int i,j,k,n;
DISABLE_INTERRUPTS(GLOBAL);
setup_adc_ports(sAN10|sAN11|VSS_VDD);
setup_adc( ADC_CLOCK_INTERNAL );
SETUP_CCP1(CCP_PWM_HALF_BRIDGE|CCP_PWM_H_H|CCP_SHUTDOWN_MODE) ;

set_tris_c(0xc0);
while(1)
{


set_adc_channel( 10 );
delay_ms(10);
i=read_adc();
delay_ms(100);
j=i/42.50+(58.5);
k=(j/1.8);
delay_ms(10);
SETUP_TIMER_2(T2_DIV_BY_1,j,1);
Pwm1con=0x04;
set_pwm1_duty(k);

}

}

also thre is a shut down command one is interrupt and another one is comparator any help me the hardware connection for comparator which pin ref and which is input
help me

 

[Pommie]

I don't fully understand your question but for proper startup of PWM, it is normal to have a pulldown on the PWM pin and only switch the pin to output when the PWM module is ready. Likewise, shutdown can be accomplished by switching the pin to input.

Mike.

 

[samuel.sam77]

am using analog input as a duty cycle value ..i need duty cycle starts from zero to adc value..like smooth start ..it mean for an examble analog out put is 60 % duty cycle so when suddenly switch on the board, the value not suddenly load to duty cycle register (i need linear )

0-1,1-2,2-3,3-4........60% with in 20 sec or 10 sec ...how the motor starts 0 -100 % like that

thank for your reply

 

[Pommie]

Before your wait(1); do the following,

Calculate k,
have a for loop from 0 to k,
set the PWM
delay 10 seconds divided by k

This will ensure that it always takes 10 seconds to get up to speed.

A variation on the above would be a while loop that slowly increased the PWM value until k was reached.

Mike.

 

[samuel.sam77]

thanks mike show me the examble code how..?