THANKS Darrel, it worked like a charm with HPWM. Any pointers as to how to do without it.

I tried FREQOUT
Code:
    FOR Freq = 3000 TO 4000 STEP 10    
        FREQOUT PortC.2,1, Freq
    NEXT Freq
but the results were not the same, not even near enough, the pulsing sound is not that prominent