Using HPWM to blink an LED?

[Christopher4187]

I'm a bit confused about using the timer1. I have read Darrel's posts on his timers and trying to follow the code myself is very confusing. Is there a step by step explanation on how to do it. I didn't see anything in the manual and if there was I didn't see it.

Thanks,

Chris

[Darrel Taylor]

Chris,

You've read this post?
http://www.picbasic.co.uk/forum/showthread.php?p=23259

What part don't you understand?

How the Timer works?
How the Interrupts work?
How the program works?
<br>

[Christopher4187]

Darrel,

Yes, I have read that post. I changed the prescaler and it does work but it's not what I am looking for because it only made the LED blink faster, not slower. I guess I was trying to solve my problem more simply. When using the HPWM command, the code is one line and as you know looks like this:

hpwm 1, 1000,1000

but when using the hpwm command, the control of the LED is more of a dimming function because it's just too fast for the naked eye see.

In my current program within the main loop, I am using a pause 1 command and counting to 1000 and then toggling the LED. I guess I was just hoping that there was a 1 line command when you can say "I want to blink the LED every 2 seconds" or something like that.

Chris

[Darrel Taylor]

Oh, I see. Sorry about that Chris, with the talk of HPWM and duty-cycle, I thought you were going for the Fader. It helps to know as many details as possible at the beginning.

I was just hoping that there was a 1 line command when you can say "I want to blink the LED every 2 seconds" or something like that.

How's this look?

<font color="#0000FF"><b><i>; Initialise your Hardware first

</i></b></font><b>LED      </b><font color="#008000"><b>VAR  </b></font><b>PORTB</b>.<b>2             
ONstate  </b><font color="#008000"><b>CON  </b></font><b>1                   </b><font color="#0000FF"><b><i>; 0=ON when LOW, 1=ON when HIGH(default)

</i></b></font><font color="#008000"><b>INCLUDE </b></font><font color="#FF0000">&quot;SingleLEDblinker.bas&quot;

</font><font color="#000080">@ Blink  10, 190                  </font><font color="#0000FF"><b><i>; Blink 1/10 sec every 2 seconds

</i></b></font><b>Main</b>:
  <font color="#008000"><b>PAUSE </b></font><b>1000
</b><font color="#008000"><b>GOTO </b></font><b>Main</b>

It uses DT_INTS-18 to get interrupts from timer1 every 10 ms, or 100hz.
But you can just change it to DT_INTS-14 if using a 16F.

It simply turns the LED ON, OFF for a number of periods specified by the constants provided.

@ Blink 10, 190

Will turn the LED ON for 10/100th's sec (0.1 sec). and OFF for 190/100th's (1.9 sec). The total of the two, determines the length of time between pulses (2.0 sec) and must be under 65535, which is 655 seconds.

Other included commands are ...

@ NoBlink ONtime, OFFtime

This is the same as Blink, except that it doesn't start Blinking. It simply defines the ON and OFF times in preperation for a ...

@ BlinkON

which can then be placed somewhere else in the program to actually Start the LED blinking.

Of course you need the ...

@ BlinkOFF

To round things out. And now it allows you to make a more custom blinking sequence.

For instance, this one will "FLASH" the LED every second, instead of just Blinking it. Giving more of an "ALERT!" type of indication.

<font color="#0000FF"><b><i>; Initialise your Hardware first

</i></b></font><b>LED      </b><font color="#008000"><b>VAR  </b></font><b>PORTB</b>.<b>2             
ONstate  </b><font color="#008000"><b>CON  </b></font><b>1                   </b><font color="#0000FF"><b><i>; 0=ON when LOW, 1=ON when HIGH(default)

</i></b></font><font color="#008000"><b>INCLUDE </b></font><font color="#FF0000">&quot;SingleLEDblinker.bas&quot;

</font><font color="#000080">@ NoBlink  3, 3                   </font><font color="#0000FF"><b><i>; set Blink to 3/100 ON, 3/100 OFF
</i></b></font><font color="#008000"><b>PAUSE </b></font><b>2000                        </b><font color="#0000FF"><b><i>; just to verify it's not blinking

</i></b></font><b>Main</b>:
<font color="#000080">@ BlinkON                         </font><font color="#0000FF"><b><i>; Start Flashing LED
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>1000                      </b><font color="#0000FF"><b><i>;  continue for 1 second
</i></b></font><font color="#000080">@ BlinkOFF                        </font><font color="#0000FF"><b><i>; Stop Flashing LED
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>1000                      </b><font color="#0000FF"><b><i>;  for another second
</i></b></font><font color="#008000"><b>GOTO </b></font><b>Main
</b>

Or here's several different Blink sequences ...

<font color="#0000FF"><b><i>; Initialise your Hardware first

</i></b></font><b>LED      </b><font color="#008000"><b>VAR  </b></font><b>PORTB</b>.<b>2             
ONstate  </b><font color="#008000"><b>CON  </b></font><b>1                   </b><font color="#0000FF"><b><i>; 0=ON when LOW, 1=ON when HIGH

</i></b></font><font color="#008000"><b>INCLUDE </b></font><font color="#FF0000">&quot;SingleLEDblinker.bas&quot;


</font><b>Main</b>:
  @ <b>Blink  2</b>, <b>10                  </b><font color="#0000FF"><b><i>; .02 ON, .1 OFF
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>4000
  
  </b>@ <b>Blink  10</b>, <b>10                 </b><font color="#0000FF"><b><i>; .1 ON, .1 OFF
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>4000
  
  </b>@ <b>Blink  20</b>, <b>10                 </b><font color="#0000FF"><b><i>; .2 ON, .2 OFF
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>4000
  
  </b>@ <b>Blink  50</b>, <b>50                 </b><font color="#0000FF"><b><i>; .5 ON, .5 OFF
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>4000

  </b>@ <b>Blink  50</b>, <b>10                 </b><font color="#0000FF"><b><i>; .5 ON, .1 OFF
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>5000
  
  </b>@ <b>BlinkOFF                      </b><font color="#0000FF"><b><i>; stop blinking
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>3000
  
  </b>@ <b>BlinkON                       </b><font color="#0000FF"><b><i>; resume blinking at same rate
  </i></b></font><font color="#008000"><b>PAUSE </b></font><b>5000
</b><font color="#008000"><b>GOTO </b></font><b>Main

</b>

[Christopher4187]

Darrel,

Wow, that's great! I didn't expect you to write it for me but I'm certainly not complaining. I'm still trying to learn more about PBP and this will help me a lot.

Thanks,

Chris