On Interrupt question

[Archilochus]

Hi Pablo,
As sougata mentioned, you'll have problems with switch bounce and button press duration causing repeated interrupt flag resets.

Since your code is not 'seeing' an interrupt until after the PWM statements are finished, why not just test the state of the interrupt flag in the pauses in between your PWM loops?

As far as interrupting on power up without a button press, you might try a bit a a pause at the start of the program, then clear the interrupt flags.

Arch

EDIT - ooh... that won't work 'cause it won't sort out the different buttons - darn!

[sougata]

Hi,

On a closer look at your prog I found that you have timer0 to use external clock via RA4. Possibily you did this because there is no timer0 enable disable bit. You wanted your timer not to work. But you have kept the input floating. Spurious counting is going on. Also you have turned on the timer0 interrupt bit in your intcon settings. So a timer0 overflow would trigger the interrupt.

So my suggestions :

1. Disable the T0IE bit

Regards

Sougata

[peu]

Thanks Sougata, I changed that bit and now it works as expected.

A single bit keep me puzzled half week, you gotta love pics...

Here is the working example, so others can learn too:

@ device pic16F628A, intrc_osc_noclkout, wdt_on, mclr_off, protect_off
DEFINE OSC 4

trisb   =%11111111
trisa   =%00000000
cmcon   =%00000111  'Comparators Off
vrcon   =%00000000
intcon  =%10001000'interrupts enable // was  %10101000  
'OPTION_REG =%11010001 

but1    var PORTB.4
but2    var PORTB.5
ledwork var PORTA.0
led1    var PORTA.1
led2    var PORTA.2
led3    var PORTA.3
rs      var PORTb.2


conta   var byte

porta=0
portb=0

on interrupt goto interrupcion

SerOut rs,2,[" ",10,13]
SerOut rs,2,["Begin",10,13]


LOOP:

SerOut rs,2,["Loop",10,13]

for conta=0 to 255 step 16  'working led rise routine
    pwm ledwork, conta, 10  
next conta
high ledwork

for conta =0 to 10
    pause 10
next conta

low led1   'set button status leds off
low led2
low led3


goto loop

end
disable 
interrupcion:
SerOut rs,2,["Interrupt",10,13]
    intcon.0=0
    intcon.1=0
    intcon.2=0
        if but1=1 then
             but1=0
            high led1
            SerOut rs,2,["Set",10,13]

        endif
        if but2=1 then
             but2=0
           high led2
           SerOut rs,2,["Mode",10,13]
        endif
high led3       

    resume
enable

I commented out the OPTION_REG because the program worked ok with and without it. Of course the serouts can be removed, I use them to know where the program is.

Thanks to all for the help provided


Pablo

[sougata]

Hi,

In helping you out I also added my experience. It really feels good when a puzzle gets solved. If you hadn't given the hints that it is jumping to the interrupt even without a button pressed I couldn't have pointed it out. So the credit goes to you for all the labour and time spent.This is only the beginning now concentrate on the PWM part and add some sparkle to your design.

I myself do not rely on the PBP interrupt and tend to use asm as my apps demand.It is not that tough if you give it a try. I am a complete self-taught without much of an academic background. My schedule doesn't permit me always to be active in this forum still I love to.

I am myself very much facinated with RGB LEDs and plan to design an ambilight as in the Phillips plasma TVs. (I cannot afford a LCD or Plasma)But everytime my hobby gets the least attention due to job pressure. I am still in my struggling phase to establish myself as a PIC programmer. I live in a city where neither PICs nor RGB LEDs are easily available. I have to get them from another metro and it is costly in terms of our economy. Still with all of you around I know I am not alone. Thanks to this forum and all PICers out there.

Have a great PICing time.

Regards

Sougata

[peu]

Here is what I did with the previous version that did not used interrupts, just a simple loop of 6 for-next:

What happens when you mix: A toilet scrub and a vase

I hope you didn't bet on this art deco artifact :



Well, you need to add some electronics to the mix: a pic microcontroller, some mosfets, a few resistors, a few luxeon leds, a heatsink, a difuser and a li-ion battery...

and you get this:

luxeons attached to heatsink and difuser over leds:



here is a sequence of frames:


If you can view DivX files, here is the complete color sweep (480k)


Hope you all like it


Pablo

[sougata]

Hi,

Hats off to your vase. Nifty stuff. How about adding a beat detector with a mic input that adapts your PIC to music playin around.




Regards

Sougata