Thanks Alain, that was it!

I changed those to:
Code:
bsf INTCON,5        ;enable timer0 interrupt

and 

bcf INTCON,5        ;disable timer0 interrupt
and now the pulse runs smoothly. Only I don't get the initial set timer0 to 0, then add the second half of pulse width. I only get the second half where TMR0=pulse. So pulse width is between 0 and 1ms.

But I will work on that!

Thanks again,

Walter