If my reading between lines is close enough:

What he's calling "edge" triggering is.. that sort of detector, commonly using a Schmitt Trigger circuit: a feedback device which enhances the risetime via.. yup pos feedback! to give a thus faster dV/dt as a trigger pulse. What he calls "level triggering" implies an intentionally 'slower" device which is not concerned with dV/dt so much as just "change state when V= x.yz V".

Guess I'll poke around a bit; hard to see how same line from an "Irq detector" under s/w control - could parse the two - but it seems that the Vectra didn't.. too well. How'd ya find That!?

(It's amazing the amount of stuff you can see with a real analog GHz scope on these boards - let alone decipher)


A.