Why no analog external trigger for Oscilloscope function

[Barney]

Just "discovered" the AD2 and am very interested in it.  There is a lot of features packed into a small package.  One thing seems to be missing and I was wondering why.  There is no external analog trigger.  If I want to trigger on a specific voltage in a waveform, I have to use one of the two oscilloscope inputs.  Why was this left out?  Seems like it would be simple to add a comparator and use a DC voltage from the ADC to set the trigger level.

[attila]

Hello,

The external trigger signals on AD2 are basically digital IOs with input logic threshold of 1.5V (or 0.5V with 5th device configuration).
These can be configured to output 0/3.3V logic levels of an internal trigger signal.