How to control a PWM signal with counters in 8051

[Skylite]

Hi,

How to generate a counter for a PWM signal,

i.e., I'm getting a PWM output of 10hz frequency,and I have taken another port[for this port I need to use a counter]

and this port should toggle on/off and this signal I need to control with the generated

pwm signal by using counter operation.

For example: if counter is 0 the pwm signal should be HIGH[till it becomes 1].

Thanks in advance.

Skylite

 

[Ashutosh Bhatt]

ur question is confusing

PWM is generated using timers – inbuilt timers

why u r using counters for it

[rahul]

plz explain your problem in detail so we can help you

[Skylite]

Yes PWM is generated using timers, and i'm getting the output of it,which i'm generating in different port.

Now I have taken a seperate I/O port, where i'm getting the signal high and low, now my question is

how to control this signal for particular count/timer period[say for about maximum 5 to 10 minutes the

signal should be high and next it should be low]

Here is the part of the code:

sbit CLOCK = P2^3;

unsigned char check = 1;

void timer1_ISR`(void)

{

//timer tick functions

if(check == 0)

{

CLOCK = 0;//getting a low signal

}

else

{

CLOCK = ! CLOCK;//toggling high& low

}

}

I'm checking this in the isr routine.

Hope I have not confused, please let me know where i'm going wrong.

 

[rahul]

do you mean you are getting pwm on say port A continuously now you want this signal on port B say for 5mins…once this 5 mins are over this signal will not be on port B….and by the time on port A this signal will exist continuously. ..
am I correct?

[rahul]

for wht duration you have configured timer? ? means how much is time interval of pwm singal is high or low

[Skylite]

But I'm not generating a PWM signal on portB, just a high and low pulse,

later i'm using a transistor circuit for switching, now my concentration is only on

portB to how to hold a signal , not on portA.

[rahul]

hi can u mail all your code on my id [email protected]

[rahul]

means initially you want high low pulses in port a later on it will be on port b now fot 5 mins

[Skylite]

Ok i'll mail complete code.

[Author]

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