Howdy.... I've been trying to get a light dimmer working now for about a week. I did a good bit of reading about using a triac and zero cross over detector prior to taking on this project but I'm stuck
I believe I have all the correct code and can see on my scope things look good I'm including a picture.
What we see here on the scope is the 120vac wave along with my trigger output based on getting triggered at the zero crossover point.

Name: scope.jpg Views: 1570 Size: 31.1 KB

I'm using INT on the 12F683 and on interrupt to detect the zero crossover from an H11AA1 and then triggering a pulse out for 1500 microseconds which you can see here. So far so good this looked great to me. I am feeding this pulse to an MOC3011M in turn using the MOC3011M to trigger the gate on a BT136/BT137 (I've tried both) however even though I am only feeding what looks like an "On" pulse for 1500 microseconds the bulb appears full on no matter what I do. The logic in the on interrupt routine is pretty basic for the time being.
light=1
pauseus 1500
light=0

I'm beginning to think that the triacs I have chosen. Any ideas what type of triac I should be using if someone out there has successfully gotten this to work. If anyone has any thoughts and/or would like to see my code and schematic if they think this will help I can upload those. I'm not sure if it is my programming or schematic since I am getting a good interrupt triggering pretty much dead on the zero crossing and in turn able to turn on an output for a period of time at that zero cross over point.
Regards
David