Hi Jim,

{ I am replying without knowing your skills at electronics }

You said:
> WE wish to know how to generate the firing pulses for a TRiac using 8051.

It can be as simple as connecting the gate directly to the micro port via a 400 ohm (depends) resistor and common of triac(s) to +vcc, and here you go. Turn the port low and fire the gate. ( your micro and circuit will be at line potential and its the safety hazard).


You said:
>We must use opto-triac drivers.

You can place a simple non zero crossing opto coupler ( like MOC 3020 of Motorola) between micro and triacs. (Isolated no safety hazard, you can kiss the micro).

You said:
> we beleive and zero-crossing detectors.

With zero-crossing ones placed between micro and triac you can't do angle firing. I think zero Xing is for the protection of triac from firing surges ......

If you want to do angle firing, like you have to control the speed of morot or use it like dimmers, you have to place a non zero Xing opto triac between micro and triac for isolation (optional if you can stand mains touch), and do zero Xing detection with the micro itself so that you can fire the triac at the desired angle after the micro has detected the zero Xing.


You said:
> But how to test the same before programming the µC.

Simple:

Make a schematic and hardware. Do the coding and that's it.


Hope it helps.

Simon